Move 3rd Party source to a new directory.

Rationalise Fatfs code and fix a couple of configuration issues.
This commit is contained in:
inmarket 2014-08-13 15:48:16 +10:00
parent 10902154ae
commit efa13a879d
142 changed files with 45379 additions and 44913 deletions

View file

@ -1,120 +1,118 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
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<meta name="description" content="Open source FAT file system module for embedded projects">
<link rel="start" title="Site Top" href="../../">
<link rel="up" title="Freewares" href="../../fsw_e.html">
<link rel="alternate" hreflang="ja" title="Japanese version" href="00index_j.html">
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<title>FatFs - Generic FAT File System Module</title>
</head>
<body>
<h1>FatFs - Generic FAT File System Module</h1>
<hr>
<div class="abst">
<img src="img/layers.png" class="rset" width="245" height="255" alt="layer">
<p>FatFs is a generic FAT file system module for small embedded systems. The FatFs is written in compliance with ANSI C and completely separated from the disk I/O layer. Therefore it is independent of hardware architecture. It can be incorporated into small microcontrollers with limited resource, such as AVR, 8051, PIC, ARM, Z80, 68k and etc... Petit FatFs module is also available <a href="http://elm-chan.org/fsw/ff/00index_p.html">here</a>↗ for tiny microcontrollers.</p>
<h4>Features</h4>
<ul>
<li>Windows compatible FAT file system.</li>
<li>Platform independent. Easy to port.</li>
<li>Very small footprint for code and work area.</li>
<li>Various configuration options:
<ul>
<li>Multiple volumes (physical drives and partitions).</li>
<li>Multiple ANSI/OEM code pages including DBCS.</li>
<li>Long file name support in ANSI/OEM or Unicode.</li>
<li>RTOS support.</li>
<li>Multiple sector size support.</li>
<li>Read-only, minimized API, I/O buffer and etc...</li>
</ul>
</li>
</ul>
</div>
<div class="para">
<h3>Application Interface</h3>
<p>FatFs module provides following functions to the applications. In other words, this list describes what FatFs can do to access the FAT volumes.</p>
<ul>
<li><a href="en/mount.html">f_mount</a> - Register/Unregister a work area</li>
<li><a href="en/open.html">f_open</a> - Open/Create a file</li>
<li><a href="en/close.html">f_close</a> - Close an open file</li>
<li><a href="en/read.html">f_read</a> - Read file</li>
<li><a href="en/write.html">f_write</a> - Write file</li>
<li><a href="en/lseek.html">f_lseek</a> - Move read/write pointer, Expand file size</li>
<li><a href="en/truncate.html">f_truncate</a> - Truncate file size</li>
<li><a href="en/sync.html">f_sync</a> - Flush cached data</li>
<li><a href="en/forward.html">f_forward</a> - Forward file data to the stream</li>
<li><a href="en/stat.html">f_stat</a> - Check existance of a file or sub-directory</li>
<li><a href="en/opendir.html">f_opendir</a> - Open a directory</li>
<li><a href="en/closedir.html">f_closedir</a> - Close an open directory</li>
<li><a href="en/readdir.html">f_readdir</a> - Read a directory item</li>
<li><a href="en/mkdir.html">f_mkdir</a> - Create a sub-directory</li>
<li><a href="en/unlink.html">f_unlink</a> - Remove a file or sub-directory</li>
<li><a href="en/chmod.html">f_chmod</a> - Change attribute</li>
<li><a href="en/utime.html">f_utime</a> - Change timestamp</li>
<li><a href="en/rename.html">f_rename</a> - Rename/Move a file or sub-directory</li>
<li><a href="en/chdir.html">f_chdir</a> - Change current directory</li>
<li><a href="en/chdrive.html">f_chdrive</a> - Change current drive</li>
<li><a href="en/getcwd.html">f_getcwd</a> - Retrieve the current directory</li>
<li><a href="en/getfree.html">f_getfree</a> - Get free space on the volume</li>
<li><a href="en/getlabel.html">f_getlabel</a> - Get volume label</li>
<li><a href="en/setlabel.html">f_setlabel</a> - Set volume label</li>
<li><a href="en/mkfs.html">f_mkfs</a> - Create a file system on the drive</li>
<li><a href="en/fdisk.html">f_fdisk</a> - Divide a physical drive</li>
<li><a href="en/gets.html">f_gets</a> - Read a string</li>
<li><a href="en/putc.html">f_putc</a> - Write a character</li>
<li><a href="en/puts.html">f_puts</a> - Write a string</li>
<li><a href="en/printf.html">f_printf</a> - Write a formatted string</li>
<li><a href="en/tell.html">f_tell</a> - Get current read/write pointer</li>
<li><a href="en/eof.html">f_eof</a> - Test for end-of-file on a file</li>
<li><a href="en/size.html">f_size</a> - Get size of a file</li>
<li><a href="en/error.html">f_error</a> - Test for an error on a file</li>
</ul>
</div>
<div class="para">
<h3>Disk I/O Interface</h3>
<p>Since the FatFs module is completely separated from disk I/O layer, it requires following functions to access the storage device. When O/S related feature is enabled, it will require process/memory functions in addition. However the low level disk I/O module is not a part of FatFs module, so that it must be provided by user. The sample implementations are also available in the downloads.</p>
<ul>
<li><a href="en/dstat.html">disk_status</a> - Get device status</li>
<li><a href="en/dinit.html">disk_initialize</a> - Initialize device</li>
<li><a href="en/dread.html">disk_read</a> - Read sector(s)</li>
<li><a href="en/dwrite.html">disk_write</a> - Write sector(s)</li>
<li><a href="en/dioctl.html">disk_ioctl</a> - Control device dependent features</li>
<li><a href="en/fattime.html">get_fattime</a> - Get current time</li>
</ul>
</div>
<div class="para">
<h3>Resources</h3>
<p>The FatFs module is a free software opened for education, research and development. You can use, modify and/or redistribute it for personal projects or commercial products without any restriction under your responsibility. For further information, refer to the application note.</p>
<ul>
<li><a href="http://elm-chan.org/fsw/ff/bd/"><em>FatFs User Forum</em></a></li>
<li>Read first: <a href="en/appnote.html">FatFs module application note</a></li>
<li>Latest Information: <a href="http://elm-chan.org/fsw/ff/00index_e.html">http://elm-chan.org/fsw/ff/00index_e.html</a></li>
<li><a href="http://nemuisan.blog.bai.ne.jp/">Nemuisan's Blog</a>↗ (Well written implementations for STM32F/SDIO and LPC2300/MCI)</li>
<li><a href="http://www.siwawi.arubi.uni-kl.de/avr_projects/arm_projects/arm_memcards/index.html">ARM-Projects by Martin THOMAS</a>↗ (Examples for LPC2000, AT91SAM and STM32)</li>
<li><a href="http://www.microsoft.com/whdc/system/platform/firmware/fatgen.mspx">FAT32 Specification by Microsoft</a>↗ (The reference document on FAT file system)</li>
<li><a href="http://elm-chan.org/docs/fat.html">The basics of FAT file system [ja]</a></li>
<li><a href="http://elm-chan.org/docs/mmc/mmc_e.html">How to Use MMC/SDC</a></li>
<li><a href="img/rwtest.png">Benchmark 1</a> (ATmega64/9.2MHz with MMC via SPI, HDD/CFC via GPIO)</li>
<li><a href="img/rwtest2.png">Benchmark 2</a> (LPC2368/72MHz with MMC via MCI)</li>
<li><a href="http://members.jcom.home.ne.jp/felm/fd.mp4">Demo movie of an application</a> (this project is in ffsample.zip/lpc23xx)</li>
</ul>
</div>
<hr>
<p class="foot"><a href="../../fsw_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta http-equiv="Content-Style-Type" content="text/css">
<meta http-equiv="cache-control" content="no-cache">
<meta name="description" content="Open source FAT file system module for embedded projects">
<link rel="alternate" hreflang="ja" title="Japanese version" href="00index_j.html">
<link rel="stylesheet" href="css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - Generic FAT File System Module</title>
</head>
<body>
<h1>FatFs - Generic FAT File System Module</h1>
<hr>
<div class="abst">
<img src="img/layers.png" class="rset" width="245" height="255" alt="layer">
<p>FatFs is a generic FAT file system module for small embedded systems. The FatFs is written in compliance with ANSI C and completely separated from the disk I/O layer. Therefore it is independent of hardware architecture. It can be incorporated into small microcontrollers with limited resource, such as AVR, 8051, PIC, ARM, Z80, 68k and etc. Also Petit FatFs module for tiny microcontrollers is available <a href="http://elm-chan.org/fsw/ff/00index_p.html">here</a>.</p>
<h4>Features</h4>
<ul>
<li>Windows compatible FAT file system.</li>
<li>Platform independent. Easy to port.</li>
<li>Very small footprint for code and work area.</li>
<li>Various configuration options:
<ul>
<li>Multiple volumes (physical drives and partitions).</li>
<li>Multiple ANSI/OEM code pages including DBCS.</li>
<li>Long file name support in ANSI/OEM or Unicode.</li>
<li>RTOS support.</li>
<li>Multiple sector size support.</li>
<li>Read-only, minimized API, I/O buffer and etc...</li>
</ul>
</li>
</ul>
</div>
<div class="para">
<h3>Application Interface</h3>
<p>FatFs module provides following functions to the applications. In other words, this list describes what FatFs can do to access the FAT volumes.</p>
<ul>
<li><a href="en/mount.html">f_mount</a> - Register/Unregister a work area</li>
<li><a href="en/open.html">f_open</a> - Open/Create a file</li>
<li><a href="en/close.html">f_close</a> - Close an open file</li>
<li><a href="en/read.html">f_read</a> - Read file</li>
<li><a href="en/write.html">f_write</a> - Write file</li>
<li><a href="en/lseek.html">f_lseek</a> - Move read/write pointer, Expand file size</li>
<li><a href="en/truncate.html">f_truncate</a> - Truncate file size</li>
<li><a href="en/sync.html">f_sync</a> - Flush cached data</li>
<li><a href="en/forward.html">f_forward</a> - Forward file data to the stream</li>
<li><a href="en/stat.html">f_stat</a> - Check existance of a file or sub-directory</li>
<li><a href="en/opendir.html">f_opendir</a> - Open a directory</li>
<li><a href="en/closedir.html">f_closedir</a> - Close an open directory</li>
<li><a href="en/readdir.html">f_readdir</a> - Read a directory item</li>
<li><a href="en/mkdir.html">f_mkdir</a> - Create a sub-directory</li>
<li><a href="en/unlink.html">f_unlink</a> - Remove a file or sub-directory</li>
<li><a href="en/chmod.html">f_chmod</a> - Change attribute</li>
<li><a href="en/utime.html">f_utime</a> - Change timestamp</li>
<li><a href="en/rename.html">f_rename</a> - Rename/Move a file or sub-directory</li>
<li><a href="en/chdir.html">f_chdir</a> - Change current directory</li>
<li><a href="en/chdrive.html">f_chdrive</a> - Change current drive</li>
<li><a href="en/getcwd.html">f_getcwd</a> - Retrieve the current directory</li>
<li><a href="en/getfree.html">f_getfree</a> - Get free space on the volume</li>
<li><a href="en/getlabel.html">f_getlabel</a> - Get volume label</li>
<li><a href="en/setlabel.html">f_setlabel</a> - Set volume label</li>
<li><a href="en/mkfs.html">f_mkfs</a> - Create a file system on the drive</li>
<li><a href="en/fdisk.html">f_fdisk</a> - Divide a physical drive</li>
<li><a href="en/gets.html">f_gets</a> - Read a string</li>
<li><a href="en/putc.html">f_putc</a> - Write a character</li>
<li><a href="en/puts.html">f_puts</a> - Write a string</li>
<li><a href="en/printf.html">f_printf</a> - Write a formatted string</li>
<li><a href="en/tell.html">f_tell</a> - Get current read/write pointer</li>
<li><a href="en/eof.html">f_eof</a> - Test for end-of-file on a file</li>
<li><a href="en/size.html">f_size</a> - Get size of a file</li>
<li><a href="en/error.html">f_error</a> - Test for an error on a file</li>
</ul>
</div>
<div class="para">
<h3>Device Control Interface</h3>
<p>Since the FatFs module is a file system driver, it is completely separated from physical devices, such as memory card, harddisk and any type of storage devices. The low level device control module is not a part of FatFs module. FatFs accesses the storage device via a simple interface described below. These functions are provided by implementer. Sample implementations for some platforms are also available in the downloads.</p>
<ul>
<li><a href="en/dstat.html">disk_status</a> - Get device status</li>
<li><a href="en/dinit.html">disk_initialize</a> - Initialize device</li>
<li><a href="en/dread.html">disk_read</a> - Read sector(s)</li>
<li><a href="en/dwrite.html">disk_write</a> - Write sector(s)</li>
<li><a href="en/dioctl.html">disk_ioctl</a> - Control device dependent features</li>
<li><a href="en/fattime.html">get_fattime</a> - Get current time</li>
</ul>
</div>
<div class="para">
<h3>Resources</h3>
<p>The FatFs module is a free software opened for education, research and development. You can use, modify and/or redistribute it for personal projects or commercial products without any restriction under your responsibility. For further information, refer to the application note.</p>
<ul>
<li><a href="http://elm-chan.org/fsw/ff/bd/"><em>FatFs User Forum</em></a></li>
<li>Read first: <a href="en/appnote.html">FatFs module application note</a></li>
<li>Latest Information: <a href="http://elm-chan.org/fsw/ff/00index_e.html">http://elm-chan.org/fsw/ff/00index_e.html</a></li>
<li><a href="http://nemuisan.blog.bai.ne.jp/">Nemuisan's Blog</a>↗ (Well written implementations for STM32F/SDIO and LPC2300/MCI)</li>
<li><a href="http://www.siwawi.arubi.uni-kl.de/avr_projects/arm_projects/arm_memcards/index.html">ARM-Projects by Martin THOMAS</a>↗ (Examples for LPC2000, AT91SAM and STM32)</li>
<li><a href="http://www.microsoft.com/whdc/system/platform/firmware/fatgen.mspx">FAT32 Specification by Microsoft</a>↗ (The reference document on FAT file system)</li>
<li><a href="http://elm-chan.org/docs/fat.html">The basics of FAT file system [ja]</a></li>
<li><a href="http://elm-chan.org/docs/mmc/mmc_e.html">How to Use MMC/SDC</a></li>
<li><a href="img/rwtest.png">Benchmark 1</a> (ATmega64/9.2MHz with MMC via SPI, HDD/CFC via GPIO)</li>
<li><a href="img/rwtest2.png">Benchmark 2</a> (LPC2368/72MHz with MMC via MCI)</li>
<li><a href="http://members.jcom.home.ne.jp/felm/fd.mp4">Demo movie of an application</a> (this project is in ffsample.zip/lpc23xx)</li>
</ul>
</div>
<hr>
<p class="foot"><a href="../../fsw_e.html">Return</a></p>
</body>
</html>

View file

@ -1,118 +1,118 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="ja">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta http-equiv="Content-Style-Type" content="text/css">
<meta http-equiv="cache-control" content="no-cache">
<meta name="description" content="組み込みシステム向け汎用FATファイル・システム">
<link rel="start" title="Site Top" href="../../index_j.html">
<link rel="up" title="Freewares" href="../../fsw.html">
<link rel="alternate" hreflang="en" title="英文" href="00index_e.html">
<link rel="stylesheet" href="css_j.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs 汎用FATファイルシステム・モジュール</title>
</head>
<body>
<h1>FatFs 汎用FATファイルシステム・モジュール</h1>
<hr>
<div class="abst">
<img src="img/layers.png" class="rset" width="245" height="255" alt="layer">
<p>FatFsは小規模な組み込みシステム向けの汎用FATファイルシステム・モジュールです。ANSI C準拠でハードウェア・アーキテクチャには依存しないので、必要なワーク・エリアが確保できれば、8051, PIC, AVR, SH, Z80, 68k, H8, ARMなど安価なマイコンでも使用可能です。FatFsをシュリンクした<a href="http://elm-chan.org/fsw/ff/00index_p.html">ぷちFatFs</a>↗もあります。</p>
<h4>FatFsモジュールの特徴</h4>
<ul>
<li>Windows互換 FATファイル・システム</li>
<li>プラットフォーム非依存</li>
<li>コンパクトなコードとRAM使用量</li>
<li>多くの構成オプション:
<ul>
<li>複数のボリューム(物理ドライブ・区画)</li>
<li>DBCSを含む複数のANSI/OEMコード・ページ</li>
<li>長いファイル名(LFN) (Unicode APIも選択可)</li>
<li>マルチタスク関連</li>
<li>マルチ・セクタ・サイズ</li>
<li>リード・オンリー構成、一部APIの削除、バッファ構成、その他…</li>
</ul>
</li>
</ul>
</div>
<div class="para">
<h3>上位レイヤ・インターフェース</h3>
<p>FatFsモジュールは、アプリケーション・レイヤに対し、次のファイル操作関数(API)を提供します。つまり、このリストはFatFsにできることをシンプルに示しています。</p>
<ul>
<li><a href="ja/mount.html">f_mount</a> - ワークエリアの登録・抹消</li>
<li><a href="ja/open.html">f_open</a> - ファイルのオープン・作成</li>
<li><a href="ja/close.html">f_close</a> - ファイルのクローズ</li>
<li><a href="ja/read.html">f_read</a> - ファイルの読み出し</li>
<li><a href="ja/write.html">f_write</a> - ファイルの書き込み</li>
<li><a href="ja/lseek.html">f_lseek</a> - リード/ライト・ポインタの移動, ファイルの拡張</li>
<li><a href="ja/truncate.html">f_truncate</a> - ファイル・サイズの切り詰め</li>
<li><a href="ja/sync.html">f_sync</a> - キャッシュされたデータのフラッシュ</li>
<li><a href="ja/forward.html">f_forward</a> - ファイル・データをストリーム関数に転送</li>
<li><a href="ja/stat.html">f_stat</a> - ファイル/サブ・ディレクトリの存在チェックと情報の取得</li>
<li><a href="ja/opendir.html">f_opendir</a> - ディレクトリのオープン</li>
<li><a href="ja/closedir.html">f_closedir</a> - ディレクトリのクローズ</li>
<li><a href="ja/readdir.html">f_readdir</a> - ディレクトリの読み出し</li>
<li><a href="ja/mkdir.html">f_mkdir</a> - サブ・ディレクトリの作成</li>
<li><a href="ja/unlink.html">f_unlink</a> - ファイル/サブ・ディレクトリの削除</li>
<li><a href="ja/chmod.html">f_chmod</a> - ファイル/サブ・ディレクトリの属性の変更</li>
<li><a href="ja/utime.html">f_utime</a> - ファイル/サブ・ディレクトリのタイムスタンプの変更</li>
<li><a href="ja/rename.html">f_rename</a> - ファイル/サブ・ディレクトリの名前の変更・移動</li>
<li><a href="ja/chdir.html">f_chdir</a> - カレント・ディレクトリの変更</li>
<li><a href="ja/chdrive.html">f_chdrive</a> - カレント・ドライブの変更</li>
<li><a href="ja/getcwd.html">f_getcwd</a> - カレント・ディレクトリの取得</li>
<li><a href="ja/getfree.html">f_getfree</a> - ボリューム空き領域の取得</li>
<li><a href="ja/getlabel.html">f_getlabel</a> - ボリューム・ラベルの取得</li>
<li><a href="ja/setlabel.html">f_setlabel</a> - ボリューム・ラベルの設定</li>
<li><a href="ja/mkfs.html">f_mkfs</a> - 論理ドライブのフォーマット</li>
<li><a href="ja/fdisk.html">f_fdisk</a> - 物理ドライブの分割</li>
<li><a href="ja/gets.html">f_gets</a> - 文字列の読み出し</li>
<li><a href="ja/putc.html">f_putc</a> - 文字の書き込み</li>
<li><a href="ja/puts.html">f_puts</a> - 文字列の書き込み</li>
<li><a href="ja/printf.html">f_printf</a> - 書式化文字列の書き込み</li>
<li><a href="ja/tell.html">f_tell</a> - 現在のリード/ライト・ポインタの取得</li>
<li><a href="ja/eof.html">f_eof</a> - ファイル終端の有無の取得</li>
<li><a href="ja/size.html">f_size</a> - ファイル・サイズの取得</li>
<li><a href="ja/error.html">f_error</a> - ファイルのエラーの有無の取得</li>
</ul>
</div>
<div class="para">
<h3>下位レイヤ・インターフェース</h3>
<p>FatFsモジュールは、単なるファイル・システム・レイヤなので、ストレージ・デバイス制御レイヤは含まれません。使用するストレージに対応した制御関数は、ユーザによって提供される必要があります。FatFsモジュールは、下位レイヤに対し少なくとも次のインターフェースを要求します。OS関連機能を有効にしたときは、これに加えてプロセス/メモリ関連関数も必要になります。サンプル・プロジェクトに下位レイヤの実装例を示します。</p>
<ul>
<li><a href="ja/dstat.html">disk_status</a> - デバイスの状態取得</li>
<li><a href="ja/dinit.html">disk_initialize</a> - デバイスの初期化</li>
<li><a href="ja/dread.html">disk_read</a> - データの読み出し</li>
<li><a href="ja/dwrite.html">disk_write</a> - データの書き込み</li>
<li><a href="ja/dioctl.html">disk_ioctl</a> - その他のデバイス制御</li>
<li><a href="ja/fattime.html">get_fattime</a> - 日付・時刻の取得</li>
</ul>
</div>
<div class="para">
<h3>資料</h3>
<p>FatFsモジュールはフリー・ソフトウェアとして教育・研究・開発用に公開しています。どのような利用目的個人利用から商用まででも使用・改変・配布について一切の制限はありませんが、全て利用者の責任の下での利用とします。詳しくはアプリケーション・ートを参照してください。</p>
<ul>
<li><a href="http://elm-chan.org/fsw/ff/bd/"><em>FatFsユーザ・フォーラム</em></a></li>
<li>最初に読め: <a href="ja/appnote.html">FatFsモジュール・アプリケーション・ート</a></li>
<li>最新版: <a href="http://elm-chan.org/fsw/ff/00index_j.html">http://elm-chan.org/fsw/ff/00index_j.html</a></li>
<li><a href="http://nemuisan.blog.bai.ne.jp/">ねむいさんのぶろぐ</a>↗ (Well written implementations for STM32F/SDIO and LPC2300/MCI)</li>
<li><a href="http://www.siwawi.arubi.uni-kl.de/avr_projects/arm_projects/arm_memcards/index.html">ARM-Projects by Martin THOMAS</a>↗ (Examples for LPC2000, AT91SAM and STM32)</li>
<li><a href="http://www.microsoft.com/whdc/system/platform/firmware/fatgen.mspx">FATファイル・システム仕様書 by Microsoft</a>↗ (The reference document on FAT file system)</li>
<li><a href="http://elm-chan.org/docs/fat.html">FATファイル・システム概要</a>↗ (↑を読むためのガイド)</li>
<li><a href="http://elm-chan.org/docs/mmc/mmc.html">MMCの使いかた</a></li>
<li><a href="img/rwtest.png">パフォーマンス・テスト1</a> (ATmega64/9.2MHz with MMC via SPI, HDD/CFC via GPIO)</li>
<li><a href="img/rwtest2.png">パフォーマンス・テスト2</a> (LPC2368/72MHz with MMC via MCI)</li>
</ul>
</div>
<hr>
<p class="foot"><a href="../../fsw.html">戻る</a></p>
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<title>FatFs 汎用FATファイルシステム・モジュール</title>
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<body>
<h1>FatFs 汎用FATファイルシステム・モジュール</h1>
<hr>
<div class="abst">
<img src="img/layers.png" class="rset" width="245" height="255" alt="layer">
<p>FatFsは小規模な組み込みシステム向けの汎用FATファイルシステム・モジュールです。ANSI C準拠でハードウェア・アーキテクチャには依存しないので、必要なワーク・エリアが確保できれば、8051, PIC, AVR, SH, Z80, 68k, H8, ARMなど安価なマイコンでも使用可能です。FatFsをシュリンクした<a href="http://elm-chan.org/fsw/ff/00index_p.html">ぷちFatFs</a>↗もあります。</p>
<h4>FatFsモジュールの特徴</h4>
<ul>
<li>Windows互換 FATファイル・システム</li>
<li>プラットフォーム非依存</li>
<li>コンパクトなコードとRAM使用量</li>
<li>多くの構成オプション:
<ul>
<li>複数のボリューム(物理ドライブ・区画)</li>
<li>DBCSを含む複数のANSI/OEMコード・ページ</li>
<li>長いファイル名(LFN) (Unicode APIも選択可)</li>
<li>マルチタスク関連</li>
<li>マルチ・セクタ・サイズ</li>
<li>リード・オンリー構成、一部APIの削除、バッファ構成、その他…</li>
</ul>
</li>
</ul>
</div>
<div class="para">
<h3>上位レイヤ・インターフェース</h3>
<p>FatFsモジュールは、アプリケーション・レイヤに対し、次のファイル操作関数(API)を提供します。つまり、このリストはFatFsにできることをシンプルに示しています。</p>
<ul>
<li><a href="ja/mount.html">f_mount</a> - ワークエリアの登録・抹消</li>
<li><a href="ja/open.html">f_open</a> - ファイルのオープン・作成</li>
<li><a href="ja/close.html">f_close</a> - ファイルのクローズ</li>
<li><a href="ja/read.html">f_read</a> - ファイルの読み出し</li>
<li><a href="ja/write.html">f_write</a> - ファイルの書き込み</li>
<li><a href="ja/lseek.html">f_lseek</a> - リード/ライト・ポインタの移動, ファイルの拡張</li>
<li><a href="ja/truncate.html">f_truncate</a> - ファイル・サイズの切り詰め</li>
<li><a href="ja/sync.html">f_sync</a> - キャッシュされたデータのフラッシュ</li>
<li><a href="ja/forward.html">f_forward</a> - ファイル・データをストリーム関数に転送</li>
<li><a href="ja/stat.html">f_stat</a> - ファイル/サブ・ディレクトリの存在チェックと情報の取得</li>
<li><a href="ja/opendir.html">f_opendir</a> - ディレクトリのオープン</li>
<li><a href="ja/closedir.html">f_closedir</a> - ディレクトリのクローズ</li>
<li><a href="ja/readdir.html">f_readdir</a> - ディレクトリの読み出し</li>
<li><a href="ja/mkdir.html">f_mkdir</a> - サブ・ディレクトリの作成</li>
<li><a href="ja/unlink.html">f_unlink</a> - ファイル/サブ・ディレクトリの削除</li>
<li><a href="ja/chmod.html">f_chmod</a> - ファイル/サブ・ディレクトリの属性の変更</li>
<li><a href="ja/utime.html">f_utime</a> - ファイル/サブ・ディレクトリのタイムスタンプの変更</li>
<li><a href="ja/rename.html">f_rename</a> - ファイル/サブ・ディレクトリの名前の変更・移動</li>
<li><a href="ja/chdir.html">f_chdir</a> - カレント・ディレクトリの変更</li>
<li><a href="ja/chdrive.html">f_chdrive</a> - カレント・ドライブの変更</li>
<li><a href="ja/getcwd.html">f_getcwd</a> - カレント・ディレクトリの取得</li>
<li><a href="ja/getfree.html">f_getfree</a> - ボリューム空き領域の取得</li>
<li><a href="ja/getlabel.html">f_getlabel</a> - ボリューム・ラベルの取得</li>
<li><a href="ja/setlabel.html">f_setlabel</a> - ボリューム・ラベルの設定</li>
<li><a href="ja/mkfs.html">f_mkfs</a> - 論理ドライブのフォーマット</li>
<li><a href="ja/fdisk.html">f_fdisk</a> - 物理ドライブの分割</li>
<li><a href="ja/gets.html">f_gets</a> - 文字列の読み出し</li>
<li><a href="ja/putc.html">f_putc</a> - 文字の書き込み</li>
<li><a href="ja/puts.html">f_puts</a> - 文字列の書き込み</li>
<li><a href="ja/printf.html">f_printf</a> - 書式化文字列の書き込み</li>
<li><a href="ja/tell.html">f_tell</a> - 現在のリード/ライト・ポインタの取得</li>
<li><a href="ja/eof.html">f_eof</a> - ファイル終端の有無の取得</li>
<li><a href="ja/size.html">f_size</a> - ファイル・サイズの取得</li>
<li><a href="ja/error.html">f_error</a> - ファイルのエラーの有無の取得</li>
</ul>
</div>
<div class="para">
<h3>下位レイヤ・インターフェース</h3>
<p>FatFsモジュールは、単なるファイル・システム・レイヤなので、ストレージ・デバイス制御レイヤは含まれません。使用するストレージに対応した制御関数は、ユーザによって提供される必要があります。FatFsモジュールは、下位レイヤに対し少なくとも次のインターフェースを要求します。OS関連機能を有効にしたときは、これに加えてプロセス/メモリ関連関数も必要になります。サンプル・プロジェクトに下位レイヤの実装例を示します。</p>
<ul>
<li><a href="ja/dstat.html">disk_status</a> - デバイスの状態取得</li>
<li><a href="ja/dinit.html">disk_initialize</a> - デバイスの初期化</li>
<li><a href="ja/dread.html">disk_read</a> - データの読み出し</li>
<li><a href="ja/dwrite.html">disk_write</a> - データの書き込み</li>
<li><a href="ja/dioctl.html">disk_ioctl</a> - その他のデバイス制御</li>
<li><a href="ja/fattime.html">get_fattime</a> - 日付・時刻の取得</li>
</ul>
</div>
<div class="para">
<h3>資料</h3>
<p>FatFsモジュールはフリー・ソフトウェアとして教育・研究・開発用に公開しています。どのような利用目的個人利用から商用まででも使用・改変・配布について一切の制限はありませんが、全て利用者の責任の下での利用とします。詳しくはアプリケーション・ートを参照してください。</p>
<ul>
<li><a href="http://elm-chan.org/fsw/ff/bd/"><em>FatFsユーザ・フォーラム</em></a></li>
<li>最初に読め: <a href="ja/appnote.html">FatFsモジュール・アプリケーション・ート</a></li>
<li>最新版: <a href="http://elm-chan.org/fsw/ff/00index_j.html">http://elm-chan.org/fsw/ff/00index_j.html</a></li>
<li><a href="http://nemuisan.blog.bai.ne.jp/">ねむいさんのぶろぐ</a>↗ (Well written implementations for STM32F/SDIO and LPC2300/MCI)</li>
<li><a href="http://www.siwawi.arubi.uni-kl.de/avr_projects/arm_projects/arm_memcards/index.html">ARM-Projects by Martin THOMAS</a>↗ (Examples for LPC2000, AT91SAM and STM32)</li>
<li><a href="http://www.microsoft.com/whdc/system/platform/firmware/fatgen.mspx">FATファイル・システム仕様書 by Microsoft</a>↗ (The reference document on FAT file system)</li>
<li><a href="http://elm-chan.org/docs/fat.html">FATファイル・システム概要</a>↗ (↑を読むためのガイド)</li>
<li><a href="http://elm-chan.org/docs/mmc/mmc.html">MMCの使いかた</a></li>
<li><a href="img/rwtest.png">パフォーマンス・テスト1</a> (ATmega64/9.2MHz with MMC via SPI, HDD/CFC via GPIO)</li>
<li><a href="img/rwtest2.png">パフォーマンス・テスト2</a> (LPC2368/72MHz with MMC via MCI)</li>
</ul>
</div>
<hr>
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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/appnote.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs Module Application Note</title>
</head>
<body>
<h1>FatFs Module Application Note</h1>
<ol class="toc">
<li><a href="#port">How to Port</a></li>
<li><a href="#limits">Limits</a></li>
<li><a href="#memory">Memory Usage</a></li>
<li><a href="#reduce">Module Size Reduction</a></li>
<li><a href="#lfn">Long File Name</a></li>
<li><a href="#unicode">Unicode API</a></li>
<li><a href="#reentrant">Re-entrancy</a></li>
<li><a href="#dup">Duplicated File Access</a></li>
<li><a href="#fs1">Performance Effective File Access</a></li>
<li><a href="#fs2">Considerations on Flash Memory Media</a></li>
<li><a href="#critical">Critical Section</a></li>
<li><a href="#fs3">Extended Use of FatFs API</a></li>
<li><a href="#license">About FatFs License</a></li>
</ol>
<hr>
<div class="para" id="port">
<h3>How to Port</h3>
<h4>Basic considerations</h4>
<p>The FatFs module is assuming following conditions on portability.</p>
<ul>
<li>ANSI C<br>
The FatFs module is a middleware written in ANSI C (C89). There is no platform dependence, so long as the compiler is in compliance with ANSI C.</li>
<li>Size of integer types<br>
The FatFs module assumes that size of char/short/long are 8/16/32 bit and int is 16 or 32 bit. These correspondence are defined in <tt>integer.h</tt>. This will not be a problem on most compilers. When any conflict with existing definitions is occured, you must resolve it with care.</li>
</ul>
<h4>System organizations</h4>
<p>The dependency diagram shown below is a typical configuration of the embedded system with FatFs module.</p>
<p><img src="../img/modules.png" width="580" height="280" alt="dependency diagram"></p>
<p>(a) If a working disk module with FatFs API is provided, no additional function is needed. (b) To attach existing disk drivers with different API, glue functions are needed to translate the APIs between FatFs and the drivers.</p>
<p><img src="../img/funcs.png" width="680" height="430" alt="functional diagram"></p>
<h4>Which function is required?</h4>
<p>You need to provide only low level disk I/O functions that required by FatFs module and nothing else. If a working disk module for the target is already existing, you need to write only glue functions to attach it to the FatFs module. If not, you need to port any other disk module or write it from scratch. Most of defined functions are not that always required. For example, disk write function is not required in read-only configuration. Following table shows which function is required depends on configuration options.</p>
<table class="lst2">
<tr><th>Function</th><th>Required when:</th><th>Note</th></tr>
<tr><td>disk_status<br>disk_initialize<br>disk_read</td><td>Always</td><td rowspan="5">Disk I/O functions.<br>Samples available in ffsample.zip.<br>There are many implementations on the web.</td></tr>
<tr><td>disk_write<br>get_fattime<br>disk_ioctl (CTRL_SYNC)</td><td>_FS_READONLY == 0</td></tr>
<tr><td>disk_ioctl (GET_SECTOR_COUNT)<br>disk_ioctl (GET_BLOCK_SIZE)</td><td>_USE_MKFS == 1</td></tr>
<tr><td>disk_ioctl (GET_SECTOR_SIZE)</td><td>_MAX_SS != _MIN_SS</td></tr>
<tr><td>disk_ioctl (CTRL_ERASE_SECTOR)</td><td>_USE_ERASE == 1</td></tr>
<tr><td>ff_convert<br>ff_wtoupper</td><td>_USE_LFN &gt;= 1</td><td>Unicode support functions.<br>Available in option/unicode.c.</td></tr>
<tr><td>ff_cre_syncobj<br>ff_del_syncobj<br>ff_req_grant<br>ff_rel_grant</td><td>_FS_REENTRANT == 1</td><td rowspan="2">O/S dependent functions.<br>Samples available in option/syscall.c.</td></tr>
<tr><td>ff_mem_alloc<br>ff_mem_free</td><td>_USE_LFN == 3</td></tr>
</table>
</div>
<div class="para" id="limits">
<h3>Limits</h3>
<ul>
<li>FAT sub-types: FAT12, FAT16 and FAT32.</li>
<li>Number of open files: Unlimited, depends on available memory.</li>
<li>Number of volumes: Upto 10.</li>
<li>File size: Depends on FAT specs. (upto 4G-1 bytes)</li>
<li>Volume size: Depends on FAT specs. (upto 2T bytes at 512 bytes/sector)</li>
<li>Cluster size: Depends on FAT specs. (upto 64K bytes at 512 bytes/sector)</li>
<li>Sector size: Depends on FAT specs. (512..4096 bytes)</li>
</ul>
</div>
<div class="para" id="memory">
<h3>Memory Usage</h3>
<table class="lst2">
<tr><th></th><th>ARM7<small><br>32bit</small></th><th>ARM7<small><br>Thumb</small></th><th>CM3<small><br>Thumb-2</small></th><th>AVR</th><th>H8/300H</th><th>PIC24</th><th>RL78</th><th>V850ES</th><th>SH-2A</th><th>RX600</th><th>IA-32</th></tr>
<tr class="cal"> <td>Compiler</td><td>GCC</td><td>GCC</td><td>GCC</td><td>GCC</td><td>CH38</td><td>C30</td><td>CC78K0R</td><td>CA850</td><td>SHC</td><td>RXC</td><td>VC6</td></tr>
<tr class="cal"> <td>_WORD_ACCESS</td><td>0</td><td>0</td><td>0</td><td>1</td><td>0</td><td>0</td><td>0</td><td>1</td><td>0</td><td>1</td><td>1</td></tr>
<!-- ARM Thumb CM3 AVR H8 PIC24 RL78 V850ES SH-2A RX600 IA-32 -->
<tr class="lst3 ral"><td class="cal">text (Full, R/W)</td><td>10675</td><td>7171</td><td>6617</td><td>13355</td><td>10940</td><td>11722</td><td>13262</td><td>8113</td><td>9048</td><td>6032</td><td>7952</td></tr>
<tr class="ral"> <td class="cal">text (Min, R/W)</td> <td>6727</td><td>4631</td><td>4331</td> <td>8569</td> <td>7262</td> <td>7720</td> <td>9088</td><td>5287</td><td>5800</td><td>3948</td><td>5183</td></tr>
<tr class="ral"> <td class="cal">text (Full, R/O)</td> <td>4731</td><td>3147</td><td>2889</td> <td>6235</td> <td>5170</td> <td>5497</td> <td>6482</td><td>3833</td><td>3972</td><td>2862</td><td>3719</td></tr>
<tr class="ral"> <td class="cal">text (Min, R/O)</td> <td>3559</td><td>2485</td><td>2295</td> <td>4575</td> <td>4064</td> <td>4240</td> <td>5019</td><td>2993</td><td>3104</td><td>2214</td><td>2889</td></tr>
<tr class="ral"> <td class="cal">bss</td><td>V*4 + 2</td><td>V*4 + 2</td><td>V*4 + 2</td><td>V*2 + 2</td><td>V*4 + 2</td><td>V*2 + 2</td><td>V*2 + 2</td><td>V*4 + 2</td><td>V*4 + 2</td><td>V*4 + 2</td><td>V*4 + 2</td></tr>
<tr class="ral"> <td class="cal">Work area<br>(_FS_TINY == 0)</td><td>V*560<br>+ F*550</td><td>V*560<br>+ F*550</td><td>V*560<br>+ F*550</td><td>V*560<br>+ F*544</td><td>V*560<br>+ F*550</td><td>V*560<br>+ F*544</td><td>V*560<br>+ F*544</td><td>V*560<br>+ F*544</td><td>V*560<br>+ F*550</td><td>V*560<br>+ F*550</td><td>V*560<br>+ F*550</td></tr>
<tr class="ral"> <td class="cal">Work area<br>(_FS_TINY == 1)</td><td>V*560<br>+ F*36</td><td>V*560<br>+ F*36</td><td>V*560<br>+ F*36</td><td>V*560<br>+ F*32</td><td>V*560<br>+ F*36</td><td>V*560<br>+ F*32</td><td>V*560<br>+ F*32</td><td>V*560<br>+ F*36</td><td>V*560<br>+ F*36</td><td>V*560<br>+ F*36</td><td>V*560<br>+ F*36</td></tr>
</table>
<p>These are the memory usage on some target systems with following condition. The memory sizes are in unit of byte, <em>V</em> denotes number of volumes and <em>F</em> denotes number of open files. All samples are optimezed in code size.</p>
<pre>
FatFs R0.10a options:
_FS_READONLY 0 (R/W) or 1 (R/O)
_FS_MINIMIZE 0 (Full function) or 3 (Minimized function)
_USE_STRFUNC 0 (Disable string functions)
_USE_MKFS 0 (Disable f_mkfs function)
_USE_FORWARD 0 (Disable f_forward function)
_USE_FASTSEEK 0 (Disable fast seek feature)
_CODE_PAGE 932 (Japanese Shift-JIS)
_USE_LFN 0 (Disable LFN feature)
_MAX_SS 512 (Fixed sector size)
_FS_RPATH 0 (Disable relative path feature)
_FS_LABEL 0 (Disable volume label functions)
_VOLUMES V (Number of logical drives to be used)
_MULTI_PARTITION 0 (Single partition per drive)
_FS_REENTRANT 0 (Disable thread safe)
_FS_LOCK 0 (Disable file lock control)
</pre>
</div>
<div class="para" id="reduce">
<h3>Module Size Reduction</h3>
<p>Follwing table shows which API function is removed by configuration options for the module size reduction.</p>
<table class="lst2">
<tr><td rowspan="2">Function</td><td colspan="4">_FS_MINIMIZE</td><td colspan="2">_FS_READONLY</td><td colspan="2">_USE_STRFUNC</td><td colspan="3">_FS_RPATH</td><td colspan="2">_FS_LABEL</td><td colspan="2">_USE_MKFS</td><td colspan="2">_USE_FORWARD</td><td colspan="2">_MULTI_PARTITION</td></tr>
<tr><td>0</td><td>1</td><td>2</td><td>3</td><td>0</td><td>1</td><td>0&nbsp;&nbsp;</td><td>1/2</td><td>0</td><td>1</td><td>2</td><td>0</td><td>1</td><td>0</td><td>1</td><td>0</td><td>1</td><td>0</td><td>1</td></tr>
<tr class="lst3"><td>f_mount</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_open</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_close</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_read</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_write</td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_sync</td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_lseek</td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_opendir</td><td></td><td></td><td>x</td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_closedir</td><td></td><td></td><td>x</td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_readdir</td><td></td><td></td><td>x</td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_stat</td><td></td><td>x</td><td>x</td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_getfree</td><td></td><td>x</td><td>x</td><td>x</td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_truncate</td><td></td><td>x</td><td>x</td><td>x</td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_unlink</td><td></td><td>x</td><td>x</td><td>x</td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_mkdir</td><td></td><td>x</td><td>x</td><td>x</td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_chmod</td><td></td><td>x</td><td>x</td><td>x</td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_utime</td><td></td><td>x</td><td>x</td><td>x</td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_rename</td><td></td><td>x</td><td>x</td><td>x</td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_chdir</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_chdrive</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_getcwd</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td>x</td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_getlabel</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_setlabel</td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_forward</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td></tr>
<tr><td>f_mkfs</td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_fdisk</td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td>x</td><td></td></tr>
<tr><td>f_putc</td><td></td><td></td><td></td><td></td><td></td><td>x</td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_puts</td><td></td><td></td><td></td><td></td><td></td><td>x</td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_printf</td><td></td><td></td><td></td><td></td><td></td><td>x</td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_gets</td><td></td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
</table>
</div>
<div class="para" id="lfn">
<h3>Long File Name</h3>
<p>FatFs module supports long file name (LFN). The two different file names, SFN and LFN, of a file is transparent in the file functions except for <tt>f_readdir()</tt> function. The LFN feature is disabled by default. To enable it, set <tt>_USE_LFN</tt> to 1, 2 or 3, and add <tt>option/unicode.c</tt> to the project. The LFN feature requiers a certain working buffer in addition. The buffer size can be configured by <tt>_MAX_LFN</tt> according to the available memory size. The size of long file name will reach up to 255 characters, so that the <tt>_MAX_LFN</tt> should be set to 255 for full featured LFN operation. If the size of working buffer is insufficient for the given file name, the file function fails with <tt>FR_INVALID_NAME</tt>. When enable the LFN feature with re-entrant configuration, <tt>_USE_LFN</tt> must be set to 2 or 3. In this case, the file function allocates the working buffer on the stack or heap. The working buffer occupies <tt>(_MAX_LFN + 1) * 2</tt> bytes.</p>
<table class="lst2 rset">
<caption>LFN cfg on ARM7TDMI</caption>
<tr><th>Code page</th><th>Program size</th></tr>
<tr><td>SBCS</td><td>+3.7K</td></tr>
<tr><td>932(Shift-JIS)</td><td>+62K</td></tr>
<tr><td>936(GBK)</td><td>+177K</td></tr>
<tr><td>949(Korean)</td><td>+139K</td></tr>
<tr><td>950(Big5)</td><td>+111K</td></tr>
</table>
<p>When the LFN feature is enabled, the module size will be increased depends on the selected code page. Right table shows how many bytes increased when LFN feature is enabled with some code pages. Especially, in the CJK region, tens of thousands of characters are being used. Unfortunately, it requires a huge OEM-Unicode bidirectional conversion table and the module size will be drastically increased that shown in the table. As the result, the FatFs with LFN feature with those code pages will not able to be implemented to most 8-bit microcontrollers.</p>
<p>Note that the LFN feature on the FAT file system is a patent of Microsoft Corporation. This is not the case on FAT32 but most FAT32 drivers come with the LFN feature. FatFs can swich the LFN feature off by configuration option. When enable LFN feature on the commercial products, a license from Microsoft may be required depends on the final destination.</p>
</div>
<div class="para" id="unicode">
<h3>Unicode API</h3>
<p>By default, FatFs uses ANSI/OEM code set on the API under LFN configuration. FatFs can also switch the character encoding to Unicode on the API (<tt>_LFN_UNICODE</tt>). This means the FatFs supports the True-LFN feature. For more information, refer to the description in the <a href="filename.html">file name</a>.</p>
</div>
<div class="para" id="reentrant">
<h3>Re-entrancy</h3>
<p>The file operations to the different volume is always re-entrant and can work simultaneously. The file operations to the same volume is not re-entrant but it can also be configured to thread-safe with <tt>_FS_REENTRANT</tt> option. In this case, also the OS dependent synchronization object control functions, <tt>ff_cre_syncobj(), ff_del_syncobj(), ff_req_grant() and ff_rel_grant()</tt> must be added to the project.</p>
<p>When a file function is called while the volume is in use by any other task, the file function is suspended until that task leaves file function. If wait time exceeded a period defined by <tt>_TIMEOUT</tt>, the file function will abort with <tt>FR_TIMEOUT</tt>. The timeout feature might not be supported by some RTOS.</p>
<p>There is an exception for <tt>f_mount(), f_mkfs(), f_fdisk()</tt> function. These functions are not re-entrant to the same volume or corresponding physical drive. When use these functions, all other tasks must unmount the volume and avoid to access the volume.</p>
<p>Note that this section describes on the re-entrancy of the FatFs module itself but also the low level disk I/O layer will need to be re-entrant.</p>
</div>
<div class="para" id="dup">
<h3>Duplicated File Access</h3>
<p>FatFs module does not support the read/write collision control of duplicated open to a file. The duplicated open is permitted only when each of open method to a file is read mode. The duplicated open with one or more write mode to a file is always prohibited, and also open file must not be renamed and deleted. A violation of these rules can cause data colluption.</p>
<p>The file lock control can also be available by <tt>_FS_LOCK</tt> option. The value defines the number of open objects to manage simultaneously. In this case, if any open, rename or remove that violating the file shareing rule that described above is attempted, the file function will fail with <tt>FR_LOCKED</tt>. If number of open files and sub-directories gets larger than <tt>_FS_LOCK</tt>, the open function will fail with <tt>FR_TOO_MANY_OPEN_FILES</tt>.</p>
</div>
<div class="para" id="fs1">
<h3>Performance Effective File Access</h3>
<p>For good read/write throughput on the small embedded systems with limited size of memory, application programmer should consider what process is done in the FatFs module. The file data on the volume is transferred in following sequence by <tt>f_read()</tt> function.</p>
<p>Figure 1. Sector misaligned read (short)<br>
<img src="../img/f1.png" width="490" height="110" alt="">
</p>
<p>Figure 2. Sector misaligned read (long)<br>
<img src="../img/f2.png" width="490" height="140" alt="">
</p>
<p>Figure 3. Fully sector aligned read<br>
<img src="../img/f3.png" width="490" height="119" alt="">
</p>
<p>The file I/O buffer is a sector buffer to read/write a partial data on the sector. The sector buffer is either file private sector buffer on each file object or shared sector buffer in the file system object. The buffer configuration option <tt>_FS_TINY</tt> determins which sector buffer is used for the file data transfer. When tiny buffer (1) is selected, data memory consumption is reduced 512 bytes each file object. In this case, FatFs module uses only a sector buffer in the file system object for file data transfer and FAT/directory access. The disadvantage of the tiny buffer configuration is: the FAT data cached in the sector buffer will be lost by file data transfer and it must be reloaded at every cluster boundary. However it will be suitable for most application from view point of the decent performance and low memory comsumption.</p>
<p>Figure 1 shows that a partial sector, sector misaligned part of the file, is transferred via the file I/O buffer. At long data transfer shown in Figure 2, middle of transfer data that covers one or more sector is transferred to the application buffer directly. Figure 3 shows that the case of entier transfer data is aligned to the sector boundary. In this case, file I/O buffer is not used. On the direct transfer, the maximum extent of sectors are read with <tt>disk_read()</tt> function at a time but the multiple sector transfer is divided at cluster boundary even if it is contiguous.</p>
<p>Therefore taking effort to sector aligned read/write accesss eliminates buffered data transfer and the read/write performance will be improved. Besides the effect, cached FAT data will not be flushed by file data transfer at the tiny configuration, so that it can achieve same performance as non-tiny configuration with small memory footprint.</p>
</div>
<div class="para" id="fs2">
<h3>Considerations on Flash Memory Media</h3>
<p>To maximize the write performance of flash memory media, such as SDC, CFC and U Disk, it must be controlled in consideration of its characteristitcs.</p>
<h4>Using Mutiple-Sector Write</h4>
<div class="rset">
Figure 6. Comparison between Multiple/Single Sector Write<br>
<img src="../img/f6.png" width="630" height="148" alt="fig.6">
</div>
<p>The write throughput of the flash memory media becomes the worst at single sector write transaction. The write throughput increases as the number of sectors per a write transaction. This effect more appers at faster interface speed and the performance ratio often becomes grater than ten. <a href="../img/rwtest2.png">This graph</a> is clearly explaining how fast is multiple block write (W:16K, 32 sectors) than single block write (W:100, 1 sector), and also larger card tends to be slow at single block write. The number of write transactions also affects the life time of the flash memory media. Therefore the application program should write the data in large block as possible. The ideal write chunk size and alighment is size of sector, and size of cluster is the best. Of course all layers between the application and the storage device must have consideration on multiple sector write, however most of open-source disk drivers lack it. Do not split a multiple sector write request into single sector write transactions or the write throughput gets poor. Note that FatFs module and its sample disk drivers supprt multiple sector read/write feature. </p>
<h4>Forcing Memory Erase</h4>
<p>When remove a file with <tt>f_remove()</tt> function, the data clusters occupied by the file are marked 'free' on the FAT. But the data sectors containing the file data are not that applied any process, so that the file data left occupies a part of the flash memory array as 'live block'. If the file data is forced erased on removing the file, those data blocks will be turned in to the free block pool. This may skip internal block erase operation to the data block on next write operation. As the result the write performance might be improved. FatFs can manage this feature by setting <tt>_USE_ERASE</tt> to 1. Note that this is an expectation of internal process of the flash memory storage and not that always effective. Also <tt>f_remove()</tt> function will take a time when remove a large file. Most applications will not need this feature.</p>
</div>
<div class="para" id="critical">
<h3>Critical Section</h3>
<p>If a write operation to the FAT volume is interrupted due to any accidental failure, such as sudden blackout, incorrect disk removal and unrecoverable disk error, the FAT structure on the volume can be broken. Following images shows the critical section of the FatFs module.</p>
<div class="lset">
Figure 4. Long critical section<br>
<img src="../img/f4.png" width="320" height="436" alt="fig.4">
</div>
<div class="lset">
Figure 5. Minimized critical section<br>
<img src="../img/f5.png" width="320" height="436" alt="fig.5">
</div>
<br class="clr">
<p>An interruption in the red section can cause a cross link; as a result, the object being changed can be lost. If an interruption in the yellow section is occured, there is one or more possibility listed below.</p>
<ul>
<li>The file data being rewrited is collapsed.</li>
<li>The file being appended returns initial state.</li>
<li>The file created as new is gone.</li>
<li>The file created as new or overwritten remains but no content.</li>
<li>Efficiency of disk use gets worse due to lost clusters.</li>
</ul>
<p>Each case does not affect the files that not opened in write mode. To minimize risk of data loss, the critical section can be minimized by minimizing the time that file is opened in write mode or using <tt>f_sync()</tt> function as shown in Figure 5.</p>
</div>
<div class="para" id="fs3">
<h3>Extended Use of FatFs API</h3>
<p>These are examples of extended use of FatFs APIs. New item will be added whenever a useful code is found.</p>
<ol>
<li><a href="../img/app1.c">Open or create a file for append</a></li>
<li><a href="../img/app2.c">Empty a directory</a></li>
<li><a href="../img/app3.c">Allocate contiguous area to the file</a></li>
<li><a href="../img/app4.c">Function/Compatible checker for low level disk I/O module</a></li>
</ol>
</div>
<div class="para" id="license">
<h3>About FatFs License</h3>
<p>FatFs has being developped as a personal project of author, ChaN. It is free from the code anyone else wrote. Following code block shows a copy of the FatFs license document that included in the source files.</p>
<pre>/*----------------------------------------------------------------------------/
/ FatFs - FAT file system module R0.10b (C)ChaN, 2014
/-----------------------------------------------------------------------------/
/ FatFs module is a generic FAT file system module for small embedded systems.
/ This is a free software that opened for education, research and commercial
/ developments under license policy of following trems.
/
/ Copyright (C) 2014, ChaN, all right reserved.
/
/ * The FatFs module is a free software and there is NO WARRANTY.
/ * No restriction on use. You can use, modify and redistribute it for
/ personal, non-profit or commercial products UNDER YOUR RESPONSIBILITY.
/ * Redistributions of source code must retain the above copyright notice.
/
/-----------------------------------------------------------------------------/</pre>
<p>Therefore FatFs license is one of the BSD-style licenses but there is a significant feature. Because FatFs is for embedded projects, the conditions of redistributions in binary form, such as embedded code, hex file, binary library and any form without source code, are not specified in order to extend usability to commercial use. The documentation of the distributions need not include about FatFs and its license document, and it may also. This is equivalent to the BSD 1-Clause License. Of course FatFs is compatible with the projects under GNU GPL. When redistribute the FatFs with any modification, the license can also be changed to GNU GPL or BSD-style license.</p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
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<h1>FatFs Module Application Note</h1>
<ol class="toc">
<li><a href="#port">How to Port</a></li>
<li><a href="#limits">Limits</a></li>
<li><a href="#memory">Memory Usage</a></li>
<li><a href="#reduce">Module Size Reduction</a></li>
<li><a href="#lfn">Long File Name</a></li>
<li><a href="#unicode">Unicode API</a></li>
<li><a href="#reentrant">Re-entrancy</a></li>
<li><a href="#dup">Duplicated File Access</a></li>
<li><a href="#fs1">Performance Effective File Access</a></li>
<li><a href="#fs2">Considerations on Flash Memory Media</a></li>
<li><a href="#critical">Critical Section</a></li>
<li><a href="#fs3">Extended Use of FatFs API</a></li>
<li><a href="#license">About FatFs License</a></li>
</ol>
<hr>
<div class="para" id="port">
<h3>How to Port</h3>
<h4>Basic considerations</h4>
<p>The FatFs module is assuming following conditions on portability.</p>
<ul>
<li>ANSI C<br>
The FatFs module is a middleware written in ANSI C (C89). There is no platform dependence, so long as the compiler is in compliance with ANSI C.</li>
<li>Size of integer types<br>
The FatFs module assumes that size of char/short/long are 8/16/32 bit and int is 16 or 32 bit. These correspondence are defined in <tt>integer.h</tt>. This will not be a problem on most compilers. When any conflict with existing definitions is occured, you must resolve it with care.</li>
</ul>
<h4>System organizations</h4>
<p>The dependency diagram shown below is a typical configuration of the embedded system with FatFs module.</p>
<p><img src="../img/modules.png" width="580" height="280" alt="dependency diagram"></p>
<p>(a) If a working disk module with FatFs API is provided, no additional function is needed. (b) To attach existing disk drivers with different API, glue functions are needed to translate the APIs between FatFs and the drivers.</p>
<p><img src="../img/funcs.png" width="680" height="430" alt="functional diagram"></p>
<h4>Which function is required?</h4>
<p>You need to provide only low level disk I/O functions that required by FatFs module and nothing else. If a working disk module for the target is already existing, you need to write only glue functions to attach it to the FatFs module. If not, you need to port any other disk module or write it from scratch. Most of defined functions are not that always required. For example, disk write function is not required in read-only configuration. Following table shows which function is required depends on configuration options.</p>
<table class="lst2">
<tr><th>Function</th><th>Required when:</th><th>Note</th></tr>
<tr><td>disk_status<br>disk_initialize<br>disk_read</td><td>Always</td><td rowspan="5">Disk I/O functions.<br>Samples available in ffsample.zip.<br>There are many implementations on the web.</td></tr>
<tr><td>disk_write<br>get_fattime<br>disk_ioctl (CTRL_SYNC)</td><td>_FS_READONLY == 0</td></tr>
<tr><td>disk_ioctl (GET_SECTOR_COUNT)<br>disk_ioctl (GET_BLOCK_SIZE)</td><td>_USE_MKFS == 1</td></tr>
<tr><td>disk_ioctl (GET_SECTOR_SIZE)</td><td>_MAX_SS != _MIN_SS</td></tr>
<tr><td>disk_ioctl (CTRL_ERASE_SECTOR)</td><td>_USE_ERASE == 1</td></tr>
<tr><td>ff_convert<br>ff_wtoupper</td><td>_USE_LFN &gt;= 1</td><td>Unicode support functions.<br>Available in option/unicode.c.</td></tr>
<tr><td>ff_cre_syncobj<br>ff_del_syncobj<br>ff_req_grant<br>ff_rel_grant</td><td>_FS_REENTRANT == 1</td><td rowspan="2">O/S dependent functions.<br>Samples available in option/syscall.c.</td></tr>
<tr><td>ff_mem_alloc<br>ff_mem_free</td><td>_USE_LFN == 3</td></tr>
</table>
</div>
<div class="para" id="limits">
<h3>Limits</h3>
<ul>
<li>FAT sub-types: FAT12, FAT16 and FAT32.</li>
<li>Number of open files: Unlimited, depends on available memory.</li>
<li>Number of volumes: Upto 10.</li>
<li>File size: Depends on the FAT specs. (upto 4G-1 bytes)</li>
<li>Volume size: Depends on the FAT specs. (upto 2T bytes at 512 bytes/sector)</li>
<li>Cluster size: Depends on the FAT specs. (upto 64K bytes at 512 bytes/sector)</li>
<li>Sector size: Depends on the FAT specs. (512, 1024, 2048 and 4096 bytes)</li>
</ul>
</div>
<div class="para" id="memory">
<h3>Memory Usage</h3>
<table class="lst2">
<tr><th></th><th>ARM7<small><br>32bit</small></th><th>ARM7<small><br>Thumb</small></th><th>CM3<small><br>Thumb-2</small></th><th>AVR</th><th>H8/300H</th><th>PIC24</th><th>RL78</th><th>V850ES</th><th>SH-2A</th><th>RX600</th><th>IA-32</th></tr>
<tr class="cal"> <td>Compiler</td><td>GCC</td><td>GCC</td><td>GCC</td><td>GCC</td><td>CH38</td><td>C30</td><td>CC78K0R</td><td>CA850</td><td>SHC</td><td>RXC</td><td>VC6</td></tr>
<tr class="cal"> <td>_WORD_ACCESS</td><td>0</td><td>0</td><td>0</td><td>1</td><td>0</td><td>0</td><td>0</td><td>1</td><td>0</td><td>1</td><td>1</td></tr>
<!-- ARM Thumb CM3 AVR H8 PIC24 RL78 V850ES SH-2A RX600 IA-32 -->
<tr class="lst3 ral"><td class="cal">text (Full, R/W)</td><td>10675</td><td>7171</td><td>6617</td><td>13355</td><td>10940</td><td>11722</td><td>13262</td><td>8113</td><td>9048</td><td>6032</td><td>7952</td></tr>
<tr class="ral"> <td class="cal">text (Min, R/W)</td> <td>6727</td><td>4631</td><td>4331</td> <td>8569</td> <td>7262</td> <td>7720</td> <td>9088</td><td>5287</td><td>5800</td><td>3948</td><td>5183</td></tr>
<tr class="ral"> <td class="cal">text (Full, R/O)</td> <td>4731</td><td>3147</td><td>2889</td> <td>6235</td> <td>5170</td> <td>5497</td> <td>6482</td><td>3833</td><td>3972</td><td>2862</td><td>3719</td></tr>
<tr class="ral"> <td class="cal">text (Min, R/O)</td> <td>3559</td><td>2485</td><td>2295</td> <td>4575</td> <td>4064</td> <td>4240</td> <td>5019</td><td>2993</td><td>3104</td><td>2214</td><td>2889</td></tr>
<tr class="ral"> <td class="cal">bss</td><td>V*4 + 2</td><td>V*4 + 2</td><td>V*4 + 2</td><td>V*2 + 2</td><td>V*4 + 2</td><td>V*2 + 2</td><td>V*2 + 2</td><td>V*4 + 2</td><td>V*4 + 2</td><td>V*4 + 2</td><td>V*4 + 2</td></tr>
<tr class="ral"> <td class="cal">Work area<br>(_FS_TINY == 0)</td><td>V*560<br>+ F*550</td><td>V*560<br>+ F*550</td><td>V*560<br>+ F*550</td><td>V*560<br>+ F*544</td><td>V*560<br>+ F*550</td><td>V*560<br>+ F*544</td><td>V*560<br>+ F*544</td><td>V*560<br>+ F*544</td><td>V*560<br>+ F*550</td><td>V*560<br>+ F*550</td><td>V*560<br>+ F*550</td></tr>
<tr class="ral"> <td class="cal">Work area<br>(_FS_TINY == 1)</td><td>V*560<br>+ F*36</td><td>V*560<br>+ F*36</td><td>V*560<br>+ F*36</td><td>V*560<br>+ F*32</td><td>V*560<br>+ F*36</td><td>V*560<br>+ F*32</td><td>V*560<br>+ F*32</td><td>V*560<br>+ F*36</td><td>V*560<br>+ F*36</td><td>V*560<br>+ F*36</td><td>V*560<br>+ F*36</td></tr>
</table>
<p>These are the memory usage on some target systems with following condition. The memory sizes are in unit of byte, <em>V</em> denotes number of volumes and <em>F</em> denotes number of open files. All samples are optimezed in code size.</p>
<pre>
FatFs R0.10a options:
_FS_READONLY 0 (R/W) or 1 (R/O)
_FS_MINIMIZE 0 (Full function) or 3 (Minimized function)
_USE_STRFUNC 0 (Disable string functions)
_USE_MKFS 0 (Disable f_mkfs function)
_USE_FORWARD 0 (Disable f_forward function)
_USE_FASTSEEK 0 (Disable fast seek feature)
_CODE_PAGE 932 (Japanese Shift-JIS)
_USE_LFN 0 (Disable LFN feature)
_MAX_SS 512 (Fixed sector size)
_FS_RPATH 0 (Disable relative path feature)
_FS_LABEL 0 (Disable volume label functions)
_VOLUMES V (Number of logical drives to be used)
_MULTI_PARTITION 0 (Single partition per drive)
_FS_REENTRANT 0 (Disable thread safe)
_FS_LOCK 0 (Disable file lock control)
</pre>
</div>
<div class="para" id="reduce">
<h3>Module Size Reduction</h3>
<p>Follwing table shows which API function is removed by configuration options for the module size reduction.</p>
<table class="lst2">
<tr><td rowspan="2">Function</td><td colspan="4">_FS_MINIMIZE</td><td colspan="2">_FS_READONLY</td><td colspan="2">_USE_STRFUNC</td><td colspan="3">_FS_RPATH</td><td colspan="2">_FS_LABEL</td><td colspan="2">_USE_MKFS</td><td colspan="2">_USE_FORWARD</td><td colspan="2">_MULTI_PARTITION</td></tr>
<tr><td>0</td><td>1</td><td>2</td><td>3</td><td>0</td><td>1</td><td>0&nbsp;&nbsp;</td><td>1/2</td><td>0</td><td>1</td><td>2</td><td>0</td><td>1</td><td>0</td><td>1</td><td>0</td><td>1</td><td>0</td><td>1</td></tr>
<tr class="lst3"><td>f_mount</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_open</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_close</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_read</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_write</td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_sync</td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_lseek</td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_opendir</td><td></td><td></td><td>x</td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_closedir</td><td></td><td></td><td>x</td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_readdir</td><td></td><td></td><td>x</td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_stat</td><td></td><td>x</td><td>x</td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_getfree</td><td></td><td>x</td><td>x</td><td>x</td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_truncate</td><td></td><td>x</td><td>x</td><td>x</td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_unlink</td><td></td><td>x</td><td>x</td><td>x</td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_mkdir</td><td></td><td>x</td><td>x</td><td>x</td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_chmod</td><td></td><td>x</td><td>x</td><td>x</td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_utime</td><td></td><td>x</td><td>x</td><td>x</td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_rename</td><td></td><td>x</td><td>x</td><td>x</td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_chdir</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_chdrive</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_getcwd</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td>x</td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_getlabel</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_setlabel</td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_forward</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td></tr>
<tr><td>f_mkfs</td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_fdisk</td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td>x</td><td></td></tr>
<tr><td>f_putc</td><td></td><td></td><td></td><td></td><td></td><td>x</td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_puts</td><td></td><td></td><td></td><td></td><td></td><td>x</td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_printf</td><td></td><td></td><td></td><td></td><td></td><td>x</td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
<tr><td>f_gets</td><td></td><td></td><td></td><td></td><td></td><td></td><td>x</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td></tr>
</table>
</div>
<div class="para" id="lfn">
<h3>Long File Name</h3>
<p>FatFs module supports LFN (long file name). The two different file names, SFN (short file name) and LFN, of a file is transparent on the API except for <tt>f_readdir()</tt> function. The LFN feature is disabled by default. To enable it, set <tt>_USE_LFN</tt> to 1, 2 or 3, and add <tt>option/unicode.c</tt> to the project. The LFN feature requiers a certain working buffer in addition. The buffer size can be configured by <tt>_MAX_LFN</tt> according to the available memory. The length of an LFN will reach up to 255 characters, so that the <tt>_MAX_LFN</tt> should be set to 255 for full featured LFN operation. If the size of working buffer is insufficient for the input file name, the file function fails with <tt>FR_INVALID_NAME</tt>. When enable the LFN feature with re-entrant configuration, <tt>_USE_LFN</tt> must be set to 2 or 3. In this case, the file function allocates the working buffer on the stack or heap. The working buffer occupies <tt>(_MAX_LFN + 1) * 2</tt> bytes.</p>
<table class="lst2 rset">
<caption>LFN cfg on ARM7TDMI</caption>
<tr><th>Code page</th><th>Program size</th></tr>
<tr><td>SBCS</td><td>+3.7K</td></tr>
<tr><td>932(Shift-JIS)</td><td>+62K</td></tr>
<tr><td>936(GBK)</td><td>+177K</td></tr>
<tr><td>949(Korean)</td><td>+139K</td></tr>
<tr><td>950(Big5)</td><td>+111K</td></tr>
</table>
<p>When the LFN feature is enabled, the module size will be increased depends on the selected code page. Right table shows how many bytes increased when LFN feature is enabled with some code pages. Especially, in the CJK region, tens of thousands of characters are being used. Unfortunately, it requires a huge OEM-Unicode bidirectional conversion table and the module size will be drastically increased that shown in the table. As the result, the FatFs with LFN feature with those code pages will not able to be implemented to most 8-bit microcontrollers.</p>
<p>Note that the LFN feature on the FAT file system is a patent of Microsoft Corporation. This is not the case on FAT32 but most FAT32 drivers come with the LFN feature. FatFs can swich the LFN feature off by configuration option. When enable LFN feature on the commercial products, a license from Microsoft may be required depends on the final destination.</p>
</div>
<div class="para" id="unicode">
<h3>Unicode API</h3>
<p>By default, FatFs uses ANSI/OEM code set on the API under LFN configuration. FatFs can also switch the character encoding to Unicode on the API by <tt>_LFN_UNICODE</tt> option. This means that the FatFs supports the True-LFN feature. For more information, refer to the description in the <a href="filename.html">file name</a>.</p>
</div>
<div class="para" id="reentrant">
<h3>Re-entrancy</h3>
<p>The file operations to the different volume is always re-entrant and can work simultaneously. The file operations to the same volume is not re-entrant but it can also be configured to thread-safe by <tt>_FS_REENTRANT</tt> option. In this case, also the OS dependent synchronization object control functions, <tt>ff_cre_syncobj(), ff_del_syncobj(), ff_req_grant() and ff_rel_grant()</tt> must be added to the project. There are some examples in the <tt>option/syscall.c</tt>.</p>
<p>When a file function is called while the volume is in use by any other task, the file function is suspended until that task leaves the file function. If wait time exceeded a period defined by <tt>_TIMEOUT</tt>, the file function will abort with <tt>FR_TIMEOUT</tt>. The timeout feature might not be supported by some RTOS.</p>
<p>There is an exception for <tt>f_mount(), f_mkfs(), f_fdisk()</tt> function. These functions are not re-entrant to the same volume or corresponding physical drive. When use these functions, all other tasks must unmount the volume and avoid to access the volume.</p>
<p>Note that this section describes on the re-entrancy of the FatFs module itself but also the low level disk I/O layer will need to be re-entrant.</p>
</div>
<div class="para" id="dup">
<h3>Duplicated File Access</h3>
<p>FatFs module does not support the read/write collision control of duplicated open to a file. The duplicated open is permitted only when each of open method to a file is read mode. The duplicated open with one or more write mode to a file is always prohibited, and also open file must not be renamed and deleted. A violation of these rules can cause data colluption.</p>
<p>The file lock control can also be available by <tt>_FS_LOCK</tt> option. The value defines the number of open objects to manage simultaneously. In this case, if any open, rename or remove that violating the file shareing rule that described above is attempted, the file function will fail with <tt>FR_LOCKED</tt>. If number of open objects, files and sub-directories, gets larger than <tt>_FS_LOCK</tt>, the <tt>f_open(), f_optndir()</tt> function will fail with <tt>FR_TOO_MANY_OPEN_FILES</tt>.</p>
</div>
<div class="para" id="fs1">
<h3>Performance Effective File Access</h3>
<p>For good read/write throughput on the small embedded systems with limited size of memory, application programmer should consider what process is done in the FatFs module. The file data on the volume is transferred in following sequence by <tt>f_read()</tt> function.</p>
<p>Figure 1. Sector misaligned read (short)<br>
<img src="../img/f1.png" width="490" height="110" alt="">
</p>
<p>Figure 2. Sector misaligned read (long)<br>
<img src="../img/f2.png" width="490" height="140" alt="">
</p>
<p>Figure 3. Fully sector aligned read<br>
<img src="../img/f3.png" width="490" height="119" alt="">
</p>
<p>The file I/O buffer is a sector buffer to read/write a partial data on the sector. The sector buffer is either file private sector buffer on each file object or shared sector buffer in the file system object. The buffer configuration option <tt>_FS_TINY</tt> determins which sector buffer is used for the file data transfer. When tiny buffer (1) is selected, data memory consumption is reduced 512 bytes each file object. In this case, FatFs module uses only a sector buffer in the file system object for file data transfer and FAT/directory access. The disadvantage of the tiny buffer configuration is: the FAT data cached in the sector buffer will be lost by file data transfer and it must be reloaded at every cluster boundary. However it will be suitable for most application from view point of the decent performance and low memory comsumption.</p>
<p>Figure 1 shows that a partial sector, sector misaligned part of the file, is transferred via the file I/O buffer. At long data transfer shown in Figure 2, middle of transfer data that covers one or more sector is transferred to the application buffer directly. Figure 3 shows that the case of entier transfer data is aligned to the sector boundary. In this case, file I/O buffer is not used. On the direct transfer, the maximum extent of sectors are read with <tt>disk_read()</tt> function at a time but the multiple sector transfer is divided at cluster boundary even if it is contiguous.</p>
<p>Therefore taking effort to sector aligned read/write accesss eliminates buffered data transfer and the read/write performance will be improved. Besides the effect, cached FAT data will not be flushed by file data transfer at the tiny configuration, so that it can achieve same performance as non-tiny configuration with small memory footprint.</p>
</div>
<div class="para" id="fs2">
<h3>Considerations on Flash Memory Media</h3>
<p>To maximize the write performance of flash memory media, such as SDC, CFC and U Disk, it must be controlled in consideration of its characteristitcs.</p>
<h4>Using Mutiple-Sector Write</h4>
<div class="rset">
Figure 6. Comparison between Multiple/Single Sector Write<br>
<img src="../img/f6.png" width="630" height="148" alt="fig.6">
</div>
<p>The write throughput of the flash memory media becomes the worst at single sector write transaction. The write throughput increases as the number of sectors per a write transaction. This effect more appers at faster interface speed and the performance ratio often becomes grater than ten. <a href="../img/rwtest2.png">This graph</a> is clearly explaining how fast is multiple block write (W:16K, 32 sectors) than single block write (W:100, 1 sector), and also larger card tends to be slow at single block write. The number of write transactions also affects the life time of the flash memory media. Therefore the application program should write the data in large block as possible. The ideal write chunk size and alighment is size of sector, and size of cluster is the best. Of course all layers between the application and the storage device must have consideration on multiple sector write, however most of open-source disk drivers lack it. Do not split a multiple sector write request into single sector write transactions or the write throughput gets poor. Note that FatFs module and its sample disk drivers supprt multiple sector read/write feature. </p>
<h4>Forcing Memory Erase</h4>
<p>When remove a file with <tt>f_remove()</tt> function, the data clusters occupied by the file are marked 'free' on the FAT. But the data sectors containing the file data are not that applied any process, so that the file data left occupies a part of the flash memory array as 'live block'. If the file data is forced erased on removing the file, those data blocks will be turned in to the free block pool. This may skip internal block erase operation to the data block on next write operation. As the result the write performance might be improved. FatFs can manage this feature by setting <tt>_USE_ERASE</tt> to 1. Note that this is an expectation of internal process of the flash memory storage and not that always effective. Also <tt>f_remove()</tt> function will take a time when remove a large file. Most applications will not need this feature.</p>
</div>
<div class="para" id="critical">
<h3>Critical Section</h3>
<p>If a write operation to the FAT volume is interrupted due to any accidental failure, such as sudden blackout, incorrect disk removal and unrecoverable disk error, the FAT structure on the volume can be broken. Following images shows the critical section of the FatFs module.</p>
<div class="lset">
Figure 4. Long critical section<br>
<img src="../img/f4.png" width="320" height="436" alt="fig.4">
</div>
<div class="lset">
Figure 5. Minimized critical section<br>
<img src="../img/f5.png" width="320" height="436" alt="fig.5">
</div>
<br class="clr">
<p>An interruption in the red section can cause a cross link; as a result, the object being changed can be lost. If an interruption in the yellow section is occured, there is one or more possibility listed below.</p>
<ul>
<li>The file data being rewrited is collapsed.</li>
<li>The file being appended returns initial state.</li>
<li>The file created as new is gone.</li>
<li>The file created as new or overwritten remains but no content.</li>
<li>Efficiency of disk use gets worse due to lost clusters.</li>
</ul>
<p>Each case does not affect the files that not opened in write mode. To minimize risk of data loss, the critical section can be minimized by minimizing the time that file is opened in write mode or using <tt>f_sync()</tt> function as shown in Figure 5.</p>
</div>
<div class="para" id="fs3">
<h3>Extended Use of FatFs API</h3>
<p>These are examples of extended use of FatFs APIs. New item will be added whenever a useful code is found.</p>
<ol>
<li><a href="../img/app1.c">Open or create a file for append</a></li>
<li><a href="../img/app2.c">Empty a directory</a></li>
<li><a href="../img/app3.c">Allocate contiguous area to the file</a></li>
<li><a href="../img/app4.c">Function/Compatible checker for low level disk I/O module</a></li>
<li><a href="../img/mkfatimg.zip">FAT image creator</a></li>
</ol>
</div>
<div class="para" id="license">
<h3>About FatFs License</h3>
<p>FatFs has being developped as a personal project of author, ChaN. It is free from the code anyone else wrote. Following code block shows a copy of the FatFs license document that included in the source files.</p>
<pre>/*----------------------------------------------------------------------------/
/ FatFs - FAT file system module R0.10b (C)ChaN, 2014
/-----------------------------------------------------------------------------/
/ FatFs module is a generic FAT file system module for small embedded systems.
/ This is a free software that opened for education, research and commercial
/ developments under license policy of following trems.
/
/ Copyright (C) 2014, ChaN, all right reserved.
/
/ * The FatFs module is a free software and there is NO WARRANTY.
/ * No restriction on use. You can use, modify and redistribute it for
/ personal, non-profit or commercial products UNDER YOUR RESPONSIBILITY.
/ * Redistributions of source code must retain the above copyright notice.
/
/-----------------------------------------------------------------------------/</pre>
<p>Therefore FatFs license is one of the BSD-style licenses but there is a significant feature. Because FatFs is for embedded projects, the conditions of redistributions in binary form, such as embedded code, hex file, binary library or any forms without source code, are not specified in order to extend usability for commercial products. The documentation of the distributions need not include about FatFs and its license document, and it may also. This is equivalent to the BSD 1-Clause License. Of course FatFs is compatible with the projects under GNU GPL. When redistribute the FatFs with any modification or branch it as a folk, the license can also be changed to GNU GPL or BSD-style license.</p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
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<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/chdir.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_chdir</title>
</head>
<body>
<div class="para func">
<h2>f_chdir</h2>
<p>The f_chdir function changes the current directory of a drive.</p>
<pre>
FRESULT f_chdir (
const TCHAR* <span class="arg">path</span> <span class="c">/* [IN] Path name */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>path</dt>
<dd>Pointer to the null-terminated string that specifies a <a href="filename.html">directory</a> to go.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#np">FR_NO_PATH</a>,
<a href="rc.html#in">FR_INVALID_NAME</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>,
<a href="rc.html#ne">FR_NOT_ENABLED</a>,
<a href="rc.html#ns">FR_NO_FILESYSTEM</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>,
<a href="rc.html#nc">FR_NOT_ENOUGH_CORE</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_chdir()</tt> function changes the current directory of the logical drive. The current directory of a drive is initialized to the root directory when the drive is auto-mounted. Note that the current directory is retained in the each file system object so that it also affects other tasks that using the volume.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_RPATH >= 1</tt>.</p>
</div>
<div class="para use">
<h4>Example</h4>
<pre>
<span class="c">/* Change current direcoty of the current drive (dir1 under root dir) */</span>
f_chdir("/dir1");
<span class="c">/* Change current direcoty of drive 2 (parent dir) */</span>
f_chdir("2:..");
</pre>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="chdrive.html">f_chdrive</a>, <a href="getcwd.html">f_getcwd</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
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<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/chdir.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_chdir</title>
</head>
<body>
<div class="para func">
<h2>f_chdir</h2>
<p>The f_chdir function changes the current directory of a drive.</p>
<pre>
FRESULT f_chdir (
const TCHAR* <span class="arg">path</span> <span class="c">/* [IN] Path name */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>path</dt>
<dd>Pointer to the null-terminated string that specifies a <a href="filename.html">directory</a> to go.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#np">FR_NO_PATH</a>,
<a href="rc.html#in">FR_INVALID_NAME</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>,
<a href="rc.html#ne">FR_NOT_ENABLED</a>,
<a href="rc.html#ns">FR_NO_FILESYSTEM</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>,
<a href="rc.html#nc">FR_NOT_ENOUGH_CORE</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_chdir()</tt> function changes the current directory of the logical drive. The current directory of a drive is initialized to the root directory when the drive is auto-mounted. Note that the current directory is retained in the each file system object so that it also affects other tasks that using the volume.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_RPATH >= 1</tt>.</p>
</div>
<div class="para use">
<h4>Example</h4>
<pre>
<span class="c">/* Change current direcoty of the current drive (dir1 under root dir) */</span>
f_chdir("/dir1");
<span class="c">/* Change current direcoty of drive 2 (parent dir) */</span>
f_chdir("2:..");
</pre>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="chdrive.html">f_chdrive</a>, <a href="getcwd.html">f_getcwd</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,60 +1,60 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/chdrive.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_chdrive</title>
</head>
<body>
<div class="para func">
<h2>f_chdrive</h2>
<p>The f_chdrive function changes the current drive.</p>
<pre>
FRESULT f_chdrive (
const TCHAR* <span class="arg">path</span> <span class="c">/* [IN] Logical drive number */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>path</dt>
<dd>Specifies the <a href="filename.html">logical drive number</a> to be set as the current drive.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_chdrive()</tt> function changes the current drive. The initial value of the current drive number is 0. Note that the current drive is retained in a static variable so that it also affects other tasks that using the file functions.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_RPATH >= 1</tt> and <tt>_VOLUMES >= 2</tt>.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="chdir.html">f_chdir</a>, <a href="getcwd.html">f_getcwd</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/chdrive.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_chdrive</title>
</head>
<body>
<div class="para func">
<h2>f_chdrive</h2>
<p>The f_chdrive function changes the current drive.</p>
<pre>
FRESULT f_chdrive (
const TCHAR* <span class="arg">path</span> <span class="c">/* [IN] Logical drive number */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>path</dt>
<dd>Specifies the <a href="filename.html">logical drive number</a> to be set as the current drive.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_chdrive()</tt> function changes the current drive. The initial value of the current drive number is 0. Note that the current drive is retained in a static variable so that it also affects other tasks that using the file functions.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_RPATH >= 1</tt> and <tt>_VOLUMES >= 2</tt>.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="chdir.html">f_chdir</a>, <a href="getcwd.html">f_getcwd</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,89 +1,89 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/chmod.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_chmod</title>
</head>
<body>
<div class="para func">
<h2>f_chmod</h2>
<p>The f_chmod function changes the attribute of a file or sub-directory.</p>
<pre>
FRESULT f_chmod (
const TCHAR* <span class="arg">path</span>, <span class="c">/* [IN] Object name */</span>
BYTE <span class="arg">attr</span>, <span class="c">/* [IN] Attribute flags */</span>
BYTE <span class="arg">mask</span> <span class="c">/* [IN] Attribute masks */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>path</dt>
<dd>Pointer to the null-terminated string that specifies an <a href="filename.html">object</a> to be changed</dd>
<dt>attr</dt>
<dd>Attribute flags to be set in one or more combination of the following flags. The specified flags are set and others are cleard.<br>
<table class="lst">
<tr><th>Attribute</th><th>Description</th></tr>
<tr><td>AM_RDO</td><td>Read only</td></tr>
<tr><td>AM_ARC</td><td>Archive</td></tr>
<tr><td>AM_SYS</td><td>System</td></tr>
<tr><td>AM_HID</td><td>Hidden</td></tr>
</table>
</dd>
<dt>mask</dt>
<dd>Attribute mask that specifies which attribute is changed. The specified attributes are set or cleard and others are left unchanged.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#ok">FR_NO_FILE</a>,
<a href="rc.html#np">FR_NO_PATH</a>,
<a href="rc.html#in">FR_INVALID_NAME</a>,
<a href="rc.html#wp">FR_WRITE_PROTECTED</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>,
<a href="rc.html#ne">FR_NOT_ENABLED</a>,
<a href="rc.html#ns">FR_NO_FILESYSTEM</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>,
<a href="rc.html#nc">FR_NOT_ENOUGH_CORE</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_chmod()</tt> function changes the attribute of a file or sub-directory.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_READONLY == 0</tt> and <tt>_FS_MINIMIZE == 0</tt>.</p>
</div>
<div class="para use">
<h4>Example</h4>
<pre>
<span class="c">/* Set read-only flag, clear archive flag and others are left unchanged. */</span>
f_chmod("file.txt", AR_RDO, AR_RDO | AR_ARC);
</pre>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/chmod.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_chmod</title>
</head>
<body>
<div class="para func">
<h2>f_chmod</h2>
<p>The f_chmod function changes the attribute of a file or sub-directory.</p>
<pre>
FRESULT f_chmod (
const TCHAR* <span class="arg">path</span>, <span class="c">/* [IN] Object name */</span>
BYTE <span class="arg">attr</span>, <span class="c">/* [IN] Attribute flags */</span>
BYTE <span class="arg">mask</span> <span class="c">/* [IN] Attribute masks */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>path</dt>
<dd>Pointer to the null-terminated string that specifies an <a href="filename.html">object</a> to be changed</dd>
<dt>attr</dt>
<dd>Attribute flags to be set in one or more combination of the following flags. The specified flags are set and others are cleard.<br>
<table class="lst">
<tr><th>Attribute</th><th>Description</th></tr>
<tr><td>AM_RDO</td><td>Read only</td></tr>
<tr><td>AM_ARC</td><td>Archive</td></tr>
<tr><td>AM_SYS</td><td>System</td></tr>
<tr><td>AM_HID</td><td>Hidden</td></tr>
</table>
</dd>
<dt>mask</dt>
<dd>Attribute mask that specifies which attribute is changed. The specified attributes are set or cleard and others are left unchanged.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#ok">FR_NO_FILE</a>,
<a href="rc.html#np">FR_NO_PATH</a>,
<a href="rc.html#in">FR_INVALID_NAME</a>,
<a href="rc.html#wp">FR_WRITE_PROTECTED</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>,
<a href="rc.html#ne">FR_NOT_ENABLED</a>,
<a href="rc.html#ns">FR_NO_FILESYSTEM</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>,
<a href="rc.html#nc">FR_NOT_ENOUGH_CORE</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_chmod()</tt> function changes the attribute of a file or sub-directory.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_READONLY == 0</tt> and <tt>_FS_MINIMIZE == 0</tt>.</p>
</div>
<div class="para use">
<h4>Example</h4>
<pre>
<span class="c">/* Set read-only flag, clear archive flag and others are left unchanged. */</span>
f_chmod("file.txt", AR_RDO, AR_RDO | AR_ARC);
</pre>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,66 +1,66 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/close.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_close</title>
</head>
<body>
<div class="para func">
<h2>f_close</h2>
<p>The f_close function closes an open file.</p>
<pre>
FRESULT f_close (
FIL* <span class="arg">fp</span> <span class="c">/* [IN] Pointer to the file object */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameter</h4>
<dl class="par">
<dt>fp</dt>
<dd>Pointer to the open file object structure to be closed.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#io">FR_INVALID_OBJECT</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_close()</tt> function closes an open file object. If any data has been written to the file, the cached information of the file is written back to the volume. After the function succeeded, the file object is no longer valid and it can be discarded.</p>
<p>Note that if the file object is in read-only mode and <tt>_FS_LOCK</tt> option is not enabled, the file object can also be discarded without this process. However this is not recommended for future compatibility.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Always available.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a>, <a href="read.html">f_read</a>, <a href="write.html">f_write</a>, <a href="sync.html">f_sync</a>, <a href="sfile.html">FIL</a>, <a href="sfatfs.html">FATFS</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/close.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_close</title>
</head>
<body>
<div class="para func">
<h2>f_close</h2>
<p>The f_close function closes an open file.</p>
<pre>
FRESULT f_close (
FIL* <span class="arg">fp</span> <span class="c">/* [IN] Pointer to the file object */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameter</h4>
<dl class="par">
<dt>fp</dt>
<dd>Pointer to the open file object structure to be closed.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#io">FR_INVALID_OBJECT</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_close()</tt> function closes an open file object. If any data has been written to the file, the cached information of the file is written back to the volume. After the function succeeded, the file object is no longer valid and it can be discarded.</p>
<p>Note that if the file object is in read-only mode and <tt>_FS_LOCK</tt> option is not enabled, the file object can also be discarded without this process. However this is not recommended for future compatibility.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Always available.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a>, <a href="read.html">f_read</a>, <a href="write.html">f_write</a>, <a href="sync.html">f_sync</a>, <a href="sfile.html">FIL</a>, <a href="sfatfs.html">FATFS</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,64 +1,64 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/close.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_closedir</title>
</head>
<body>
<div class="para func">
<h2>f_closedir</h2>
<p>The f_closedir function closes an open directory.</p>
<pre>
FRESULT f_closedir (
DIR* <span class="arg">dp</span> <span class="c">/* [IN] Pointer to the directory object */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameter</h4>
<dl class="par">
<dt>dp</dt>
<dd>Pointer to the open directory object structure to be closed.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#io">FR_INVALID_OBJECT</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_closedir()</tt> function closes an open directory object. After the function succeeded, the directory object is no longer valid and it can be discarded.</p>
<p>Note that the directory object can also be discarded without this process if <tt>_FS_LOCK</tt> option is not enabled. However this is not recommended for future compatibility.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_MINIMIZE &lt;= 1</tt>.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="opendir.html">f_opendir</a>, <a href="readdir.html">f_readdir</a>, <a href="sdir.html">DIR</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/close.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_closedir</title>
</head>
<body>
<div class="para func">
<h2>f_closedir</h2>
<p>The f_closedir function closes an open directory.</p>
<pre>
FRESULT f_closedir (
DIR* <span class="arg">dp</span> <span class="c">/* [IN] Pointer to the directory object */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameter</h4>
<dl class="par">
<dt>dp</dt>
<dd>Pointer to the open directory object structure to be closed.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#io">FR_INVALID_OBJECT</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_closedir()</tt> function closes an open directory object. After the function succeeded, the directory object is no longer valid and it can be discarded.</p>
<p>Note that the directory object can also be discarded without this process if <tt>_FS_LOCK</tt> option is not enabled. However this is not recommended for future compatibility.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_MINIMIZE &lt;= 1</tt>.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="opendir.html">f_opendir</a>, <a href="readdir.html">f_readdir</a>, <a href="sdir.html">DIR</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,46 +1,46 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/dinit.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - disk_initialize</title>
</head>
<body>
<div class="para func">
<h2>disk_initialize</h2>
<p>The disk_initialize function initializes the storage device.</p>
<pre>
DSTATUS disk_initialize (
BYTE <span class="arg">pdrv</span> <span class="c">/* [IN] Physical drive number */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameter</h4>
<dl class="par">
<dt>pdrv</dt>
<dd>Physical drive number to identify the target device.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>This function returns a disk status as the result. For details of the disk status, refer to the <a href="dstat.html">disk_status()</a> function.</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>This function initializes a storage device and put it ready to generic read/write data. When the function succeeded, <tt>STA_NOINIT</tt> flag in the return value is cleared.</p>
<p><em>Application program MUST NOT call this function, or FAT structure on the volume can be broken. To re-initialize the file system, use <tt>f_mount()</tt> function instead.</em> This function is called at volume mount process by FatFs module to manage the media change.</p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
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<title>FatFs - disk_initialize</title>
</head>
<body>
<div class="para func">
<h2>disk_initialize</h2>
<p>The disk_initialize function initializes the storage device.</p>
<pre>
DSTATUS disk_initialize (
BYTE <span class="arg">pdrv</span> <span class="c">/* [IN] Physical drive number */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameter</h4>
<dl class="par">
<dt>pdrv</dt>
<dd>Physical drive number to identify the target device.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>This function returns a disk status as the result. For details of the disk status, refer to the <a href="dstat.html">disk_status()</a> function.</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>This function initializes a storage device and put it ready to generic read/write data. When the function succeeded, <tt>STA_NOINIT</tt> flag in the return value is cleared.</p>
<p><em>Application program MUST NOT call this function, or FAT structure on the volume can be broken. To re-initialize the file system, use <tt>f_mount()</tt> function instead.</em> This function is called at volume mount process by FatFs module to manage the media change.</p>
</div>
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<title>FatFs - disk_ioctl</title>
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<body>
<div class="para func">
<h2>disk_ioctl</h2>
<p>The disk_ioctl function cntrols device specific features and miscellaneous functions other than generic read/write.</p>
<pre>
DRESULT disk_ioctl (
BYTE <span class="arg">pdrv</span>, <span class="c">/* [IN] Drive number */</span>
BYTE <span class="arg">cmd</span>, <span class="c">/* [IN] Control command code */</span>
void* <span class="arg">buff</span> <span class="c">/* [I/O] Parameter and data buffer */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>pdrv</dt>
<dd>Physical drive number to identify the target device.</dd>
<dt>cmd</dt>
<dd>Command code.</dd>
<dt>buff</dt>
<dd>Pointer to the parameter depends on the command code. Do not care if no parameter to be passed.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Value</h4>
<dl class="ret">
<dt>RES_OK (0)</dt>
<dd>The function succeeded.</dd>
<dt>RES_ERROR</dt>
<dd>An error occured.</dd>
<dt>RES_PARERR</dt>
<dd>The command code or parameter is invalid.</dd>
<dt>RES_NOTRDY</dt>
<dd>The device has not been initialized.</dd>
</dl>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The FatFs module requires only five device independent commands described below.</p>
<table class="lst">
<caption>Standard ioctl command used by FatFs</caption>
<tr><th>Command</th><th>Description</th></tr>
<tr><td>CTRL_SYNC</td><td>Make sure that the device has finished pending write process. If the disk I/O module has a write back cache, the dirty buffers must be written back to the media immediately. Nothing to do for this command if each write operation to the media is completed within the <tt>disk_write()</tt> function. Required at <tt>_FS_READONLY == 0</tt>.</td></tr>
<tr><td>GET_SECTOR_COUNT</td><td>Returns number of available sectors on the drive into the <tt>DWORD</tt> variable pointed by <tt class="arg">buff</tt>. This command is used by only <tt>f_mkfs()</tt> and <tt>f_fdisk()</tt> function to determine the volume/partition size to be created. Required at <tt>_USE_MKFS == 1</tt> or <tt>_MULTI_PARTITION == 1</tt>.</td></tr>
<tr><td>GET_SECTOR_SIZE</td><td>Returns sector size of the media into the <tt>WORD</tt> variable pointed by <tt class="arg">buff</tt>. Valid return values of this command are 512, 1024, 2048 or 4096. This command is required at variable sector size configuration, <tt>_MAX_SS &gt; _MIN_SS</tt>. Never used at fixed sector size configuration, <tt>_MAX_SS == _MIN_SS</tt>, and it must work at that sector size.</td></tr>
<tr><td>GET_BLOCK_SIZE</td><td>Returns erase block size of the flash memory in unit of sector into the <tt>DWORD</tt> variable pointed by <tt class="arg">buff</tt>. The allowable value is from 1 to 32768 in power of 2. Return 1 if the erase block size is unknown or disk media. This command is used by only <tt>f_mkfs()</tt> function and it attempts to align data area to the erase block boundary. Required at <tt>_USE_MKFS == 1</tt>.</td></tr>
<tr><td>CTRL_ERASE_SECTOR</td><td>Informs device that the data on the block of sectors specified by a <tt>DWORD</tt> array {&lt;start sector&gt;, &lt;end sector&gt;} pointed by <tt class="arg">buff</tt> is no longer needed and may be erased. The device would force erased the memory block. This is a command similar to Trim command of ATA device. When this feature is not supported or not a flash memory media, nothing to do for this command. The FatFs does not check the result code and the file function is not affected even if the sectors ware not erased well. This command is called on removing a cluster chain and <tt>f_mkfs()</tt> function. Required at <tt>_USE_ERASE == 1</tt>.</td></tr>
</table>
<p>FatFs never uses any device dependent command and user defined command. Following table shows an example of non-standard commands usable for some applications.</p>
<table class="lst">
<caption>Example of optional ioctl command</caption>
<tr><th>Command</th><th>Description</th></tr>
<tr><td>CTRL_FORMAT</td><td>Create a physical format on the media. If <tt class="arg">buff</tt> is not null, it is pointer to the call-back function for progress notification.</td></tr>
<tr><td>CTRL_POWER_IDLE</td><td>Put the device idle state. <tt>STA_NOINIT</tt> in status flag may not be set if the device would go active state by generic read/write function.</td></tr>
<tr><td>CTRL_POWER_OFF</td><td>Put the device off state. Shut-down the power to the device and deinitialize the device interface if needed. <tt>STA_NOINIT</tt> in status flag must be set. The device goes active state by <tt>disk_initialize()</tt> function.</td></tr>
<tr><td>CTRL_LOCK</td><td>Lock media eject mechanism.</td></tr>
<tr><td>CTRL_UNLOCK</td><td>Unlock media eject mechanism.</td></tr>
<tr><td>CTRL_EJECT</td><td>Eject media cartridge. <tt>STA_NOINIT</tt> and <tt>STA_NODISK</tt> in status flag are set after the function succeeded.</td></tr>
<tr><td>MMC_GET_TYPE</td><td>Get card type. The type flags, bit0:MMCv3, bit1:SDv1, bit2:SDv2+ and bit3:LBA, is stored to a BYTE variable pointed by <tt class="arg">buff</tt>. (MMC/SDC specific command)</td></tr>
<tr><td>MMC_GET_CSD</td><td>Get CSD register into a 16-byte buffer pointed by <tt class="arg">buff</tt>. (MMC/SDC specific command)</td></tr>
<tr><td>MMC_GET_CID</td><td>Get CID register into a 16-byte buffer pointed by <tt class="arg">buff</tt>. (MMC/SDC specific command)</td></tr>
<tr><td>MMC_GET_OCR</td><td>Get OCR register into a 4-byte buffer pointed by <tt class="arg">buff</tt>. (MMC/SDC specific command)</td></tr>
<tr><td>MMC_GET_SDSTAT</td><td>Get SDSTATUS register into a 64-byte buffer pointed by <tt class="arg">buff</tt>. (SDC specific command)</td></tr>
<tr><td>ATA_GET_REV</td><td>Get the revision string into a 16-byte buffer pointed by <tt class="arg">buff</tt>. (ATA/CFC specific command)</td></tr>
<tr><td>ATA_GET_MODEL</td><td>Get the model string into a 40-byte buffer pointed by <tt class="arg">buff</tt>. (ATA/CFC specific command)</td></tr>
<tr><td>ATA_GET_SN</td><td>Get the serial number string into a 20-byte buffer pointed by <tt class="arg">buff</tt>. (ATA/CFC specific command)</td></tr>
</table>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
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<title>FatFs - disk_ioctl</title>
</head>
<body>
<div class="para func">
<h2>disk_ioctl</h2>
<p>The disk_ioctl function cntrols device specific features and miscellaneous functions other than generic read/write.</p>
<pre>
DRESULT disk_ioctl (
BYTE <span class="arg">pdrv</span>, <span class="c">/* [IN] Drive number */</span>
BYTE <span class="arg">cmd</span>, <span class="c">/* [IN] Control command code */</span>
void* <span class="arg">buff</span> <span class="c">/* [I/O] Parameter and data buffer */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>pdrv</dt>
<dd>Physical drive number to identify the target device.</dd>
<dt>cmd</dt>
<dd>Command code.</dd>
<dt>buff</dt>
<dd>Pointer to the parameter depends on the command code. Do not care if no parameter to be passed.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Value</h4>
<dl class="ret">
<dt>RES_OK (0)</dt>
<dd>The function succeeded.</dd>
<dt>RES_ERROR</dt>
<dd>An error occured.</dd>
<dt>RES_PARERR</dt>
<dd>The command code or parameter is invalid.</dd>
<dt>RES_NOTRDY</dt>
<dd>The device has not been initialized.</dd>
</dl>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The FatFs module requires only five device independent commands described below.</p>
<table class="lst">
<caption>Standard ioctl command used by FatFs</caption>
<tr><th>Command</th><th>Description</th></tr>
<tr><td>CTRL_SYNC</td><td>Make sure that the device has finished pending write process. If the disk I/O module has a write back cache, the dirty buffers must be written back to the media immediately. Nothing to do for this command if each write operation to the media is completed within the <tt>disk_write()</tt> function. Required at <tt>_FS_READONLY == 0</tt>.</td></tr>
<tr><td>GET_SECTOR_COUNT</td><td>Returns number of available sectors on the drive into the <tt>DWORD</tt> variable pointed by <tt class="arg">buff</tt>. This command is used by only <tt>f_mkfs()</tt> and <tt>f_fdisk()</tt> function to determine the volume/partition size to be created. Required at <tt>_USE_MKFS == 1</tt> or <tt>_MULTI_PARTITION == 1</tt>.</td></tr>
<tr><td>GET_SECTOR_SIZE</td><td>Returns sector size of the media into the <tt>WORD</tt> variable pointed by <tt class="arg">buff</tt>. Valid return values of this command are 512, 1024, 2048 or 4096. This command is required at variable sector size configuration, <tt>_MAX_SS &gt; _MIN_SS</tt>. Never used at fixed sector size configuration, <tt>_MAX_SS == _MIN_SS</tt>, and it must work at that sector size.</td></tr>
<tr><td>GET_BLOCK_SIZE</td><td>Returns erase block size of the flash memory in unit of sector into the <tt>DWORD</tt> variable pointed by <tt class="arg">buff</tt>. The allowable value is from 1 to 32768 in power of 2. Return 1 if the erase block size is unknown or disk media. This command is used by only <tt>f_mkfs()</tt> function and it attempts to align data area to the erase block boundary. Required at <tt>_USE_MKFS == 1</tt>.</td></tr>
<tr><td>CTRL_ERASE_SECTOR</td><td>Informs device that the data on the block of sectors specified by a <tt>DWORD</tt> array {&lt;start sector&gt;, &lt;end sector&gt;} pointed by <tt class="arg">buff</tt> is no longer needed and may be erased. The device would force erased the memory block. This is a command similar to Trim command of ATA device. When this feature is not supported or not a flash memory media, nothing to do for this command. The FatFs does not check the result code and the file function is not affected even if the sectors ware not erased well. This command is called on removing a cluster chain and <tt>f_mkfs()</tt> function. Required at <tt>_USE_ERASE == 1</tt>.</td></tr>
</table>
<p>FatFs never uses any device dependent command and user defined command. Following table shows an example of non-standard commands usable for some applications.</p>
<table class="lst">
<caption>Example of optional ioctl command</caption>
<tr><th>Command</th><th>Description</th></tr>
<tr><td>CTRL_FORMAT</td><td>Create a physical format on the media. If <tt class="arg">buff</tt> is not null, it is pointer to the call-back function for progress notification.</td></tr>
<tr><td>CTRL_POWER_IDLE</td><td>Put the device idle state. <tt>STA_NOINIT</tt> in status flag may not be set if the device would go active state by generic read/write function.</td></tr>
<tr><td>CTRL_POWER_OFF</td><td>Put the device off state. Shut-down the power to the device and deinitialize the device interface if needed. <tt>STA_NOINIT</tt> in status flag must be set. The device goes active state by <tt>disk_initialize()</tt> function.</td></tr>
<tr><td>CTRL_LOCK</td><td>Lock media eject mechanism.</td></tr>
<tr><td>CTRL_UNLOCK</td><td>Unlock media eject mechanism.</td></tr>
<tr><td>CTRL_EJECT</td><td>Eject media cartridge. <tt>STA_NOINIT</tt> and <tt>STA_NODISK</tt> in status flag are set after the function succeeded.</td></tr>
<tr><td>MMC_GET_TYPE</td><td>Get card type. The type flags, bit0:MMCv3, bit1:SDv1, bit2:SDv2+ and bit3:LBA, is stored to a BYTE variable pointed by <tt class="arg">buff</tt>. (MMC/SDC specific command)</td></tr>
<tr><td>MMC_GET_CSD</td><td>Get CSD register into a 16-byte buffer pointed by <tt class="arg">buff</tt>. (MMC/SDC specific command)</td></tr>
<tr><td>MMC_GET_CID</td><td>Get CID register into a 16-byte buffer pointed by <tt class="arg">buff</tt>. (MMC/SDC specific command)</td></tr>
<tr><td>MMC_GET_OCR</td><td>Get OCR register into a 4-byte buffer pointed by <tt class="arg">buff</tt>. (MMC/SDC specific command)</td></tr>
<tr><td>MMC_GET_SDSTAT</td><td>Get SDSTATUS register into a 64-byte buffer pointed by <tt class="arg">buff</tt>. (SDC specific command)</td></tr>
<tr><td>ATA_GET_REV</td><td>Get the revision string into a 16-byte buffer pointed by <tt class="arg">buff</tt>. (ATA/CFC specific command)</td></tr>
<tr><td>ATA_GET_MODEL</td><td>Get the model string into a 40-byte buffer pointed by <tt class="arg">buff</tt>. (ATA/CFC specific command)</td></tr>
<tr><td>ATA_GET_SN</td><td>Get the serial number string into a 20-byte buffer pointed by <tt class="arg">buff</tt>. (ATA/CFC specific command)</td></tr>
</table>
</div>
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@ -1,71 +1,71 @@
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<title>FatFs - disk_read</title>
</head>
<body>
<div class="para func">
<h2>disk_read</h2>
<p>The disk_read function reads sector(s) from the storage device.</p>
<pre>
DRESULT disk_read (
BYTE <span class="arg">pdrv</span>, <span class="c">/* [IN] Physical drive number */</span>
BYTE* <span class="arg">buff</span>, <span class="c">/* [OUT] Pointer to the read data buffer */</span>
DWORD <span class="arg">sector</span>, <span class="c">/* [IN] Start sector number */</span>
UINT <span class="arg">count</span> <span class="c">/* [IN] Number of sectros to read */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>pdrv</dt>
<dd>Physical drive number to identify the target device.</dd>
<dt>buff</dt>
<dd>Pointer to the <em>byte array</em> to store the read data.</dd>
<dt>sector</dt>
<dd>Start sector number in logical block address (LBA).</dd>
<dt>count</dt>
<dd>Number of sectors to read. FatFs specifis it in range of from 1 to 128.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Value</h4>
<dl class="ret">
<dt>RES_OK (0)</dt>
<dd>The function succeeded.</dd>
<dt>RES_ERROR</dt>
<dd>Any hard error occured during the read operation and could not recover it.</dd>
<dt>RES_PARERR</dt>
<dd>Invalid parameter.</dd>
<dt>RES_NOTRDY</dt>
<dd>The device has not been initialized.</dd>
</dl>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The memory address specified by <tt class="arg">buff</tt> is not that always aligned to word boundary because the type of argument is defined as <tt>BYTE*</tt>. The misaligned read/write request can occure at <a href="appnote.html#fs1">direct transfer</a>. If the bus architecture, especially DMA controller, does not allow misaligned memory access, it should be solved in this function. There are some workarounds described below to avoid this issue.</p>
<ul>
<li>Convert word transfer to byte transfer in this function. - Recommended.</li>
<li>For <tt>f_read()</tt>, avoid long read request that includes a whole of sector. - Direct transfer will never occure.</li>
<li>For <tt>f_read(fp, buff, btr, &amp;br)</tt>, make sure that <tt>(((UINT)buff &amp; 3) == (f_tell(fp) &amp; 3))</tt> is true. - Word aligned direct transfer is guaranteed.</li>
</ul>
<p>Generally, a multiple sector transfer request must not be split into single sector transactions to the storage device, or you will not get good read throughput.</p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
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<title>FatFs - disk_read</title>
</head>
<body>
<div class="para func">
<h2>disk_read</h2>
<p>The disk_read function reads sector(s) from the storage device.</p>
<pre>
DRESULT disk_read (
BYTE <span class="arg">pdrv</span>, <span class="c">/* [IN] Physical drive number */</span>
BYTE* <span class="arg">buff</span>, <span class="c">/* [OUT] Pointer to the read data buffer */</span>
DWORD <span class="arg">sector</span>, <span class="c">/* [IN] Start sector number */</span>
UINT <span class="arg">count</span> <span class="c">/* [IN] Number of sectros to read */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>pdrv</dt>
<dd>Physical drive number to identify the target device.</dd>
<dt>buff</dt>
<dd>Pointer to the <em>byte array</em> to store the read data.</dd>
<dt>sector</dt>
<dd>Start sector number in logical block address (LBA).</dd>
<dt>count</dt>
<dd>Number of sectors to read. FatFs specifis it in range of from 1 to 128.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Value</h4>
<dl class="ret">
<dt>RES_OK (0)</dt>
<dd>The function succeeded.</dd>
<dt>RES_ERROR</dt>
<dd>Any hard error occured during the read operation and could not recover it.</dd>
<dt>RES_PARERR</dt>
<dd>Invalid parameter.</dd>
<dt>RES_NOTRDY</dt>
<dd>The device has not been initialized.</dd>
</dl>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The memory address specified by <tt class="arg">buff</tt> is not that always aligned to word boundary because the type of argument is defined as <tt>BYTE*</tt>. The misaligned read/write request can occure at <a href="appnote.html#fs1">direct transfer</a>. If the bus architecture, especially DMA controller, does not allow misaligned memory access, it should be solved in this function. There are some workarounds described below to avoid this issue.</p>
<ul>
<li>Convert word transfer to byte transfer in this function. - Recommended.</li>
<li>For <tt>f_read()</tt>, avoid long read request that includes a whole of sector. - Direct transfer will never occure.</li>
<li>For <tt>f_read(fp, buff, btr, &amp;br)</tt>, make sure that <tt>(((UINT)buff &amp; 3) == (f_tell(fp) &amp; 3))</tt> is true. - Word aligned direct transfer is guaranteed.</li>
</ul>
<p>Generally, a multiple sector transfer request must not be split into single sector transactions to the storage device, or you will not get good read throughput.</p>
</div>
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View file

@ -1,48 +1,48 @@
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<title>FatFs - disk_status</title>
</head>
<body>
<div class="para func">
<h2>disk_status</h2>
<p>The disk_status function returns the current disk status.</p>
<pre>
DSTATUS disk_status (
BYTE <span class="arg">pdrv</span> <span class="c">/* [IN] Physical drive number */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameter</h4>
<dl class="par">
<dt>pdrv</dt>
<dd>Physical drive number to identify the target device.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>The disk status is returned in combination of following flags. FatFs refers only <tt>STA_NOINIT</tt> and <tt>STA_PROTECT</tt>.</p>
<dl class="ret">
<dt>STA_NOINIT</dt>
<dd>Indicates that the device is not initialized. This flag is set on system reset, media removal or failure of <tt>disk_initialize()</tt> function. It is cleared on <tt>disk_initialize()</tt> function succeeded. Media change that occurs asynchronously must be captured and reflect it to the status flags, or auto-mount feature will not work correctly. When media change detection feature is not supported, application program needs to de-initialize the file system object with <tt>f_mount()</tt> function after the media change.</dd>
<dt>STA_NODISK</dt>
<dd>Indicates that no medium in the drive. This is always cleared on fixed disk drive. Note that FatFs does not refer this flag.</dd>
<dt>STA_PROTECT</dt>
<dd>Indicates that the medium is write protected. This is always cleared on the drives without write protect feature. Not valid while no medium in the drive.</dd>
</dl>
</div>
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</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/dstat.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - disk_status</title>
</head>
<body>
<div class="para func">
<h2>disk_status</h2>
<p>The disk_status function returns the current disk status.</p>
<pre>
DSTATUS disk_status (
BYTE <span class="arg">pdrv</span> <span class="c">/* [IN] Physical drive number */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameter</h4>
<dl class="par">
<dt>pdrv</dt>
<dd>Physical drive number to identify the target device.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>The disk status is returned in combination of following flags. FatFs refers only <tt>STA_NOINIT</tt> and <tt>STA_PROTECT</tt>.</p>
<dl class="ret">
<dt>STA_NOINIT</dt>
<dd>Indicates that the device is not initialized. This flag is set on system reset, media removal or failure of <tt>disk_initialize()</tt> function. It is cleared on <tt>disk_initialize()</tt> function succeeded. Media change that occurs asynchronously must be captured and reflect it to the status flags, or auto-mount feature will not work correctly. When media change detection feature is not supported, application program needs to de-initialize the file system object with <tt>f_mount()</tt> function after the media change.</dd>
<dt>STA_NODISK</dt>
<dd>Indicates that no medium in the drive. This is always cleared on fixed disk drive. Note that FatFs does not refer this flag.</dd>
<dt>STA_PROTECT</dt>
<dd>Indicates that the medium is write protected. This is always cleared on the drives without write protect feature. Not valid while no medium in the drive.</dd>
</dl>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

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@ -1,76 +1,76 @@
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<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/dwrite.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - disk_write</title>
</head>
<body>
<div class="para func">
<h2>disk_write</h2>
<p>The disk_write writes sector(s) to the storage device.</p>
<pre>
DRESULT disk_write (
BYTE <span class="arg">drv</span>, <span class="c">/* [IN] Physical drive number */</span>
const BYTE* <span class="arg">buff</span>, <span class="c">/* [IN] Pointer to the data to be written */</span>
DWORD <span class="arg">sector</span>, <span class="c">/* [IN] Sector number to write from */</span>
UINT <span class="arg">count</span> <span class="c">/* [IN] Number of sectors to write */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>pdrv</dt>
<dd>Physical drive number to identify the target device.</dd>
<dt>buff</dt>
<dd>Pointer to the <em>byte array</em> to be written. The size of data to be written is sector size * <tt class="arg">count</tt> bytes.</dd>
<dt>sector</dt>
<dd>Start sector number in logical block address (LBA).</dd>
<dt>count</dt>
<dd>Number of sectors to write. FatFs specifis it in range of from 1 to 128.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<dl class="ret">
<dt>RES_OK (0)</dt>
<dd>The function succeeded.</dd>
<dt>RES_ERROR</dt>
<dd>Any hard error occured during the write operation and could not recover it.</dd>
<dt>RES_WRPRT</dt>
<dd>The medium is write protected.</dd>
<dt>RES_PARERR</dt>
<dd>Invalid parameter.</dd>
<dt>RES_NOTRDY</dt>
<dd>The device has not been initialized.</dd>
</dl>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The specified memory address is not that always aligned to word boundary because the type of pointer is defined as <tt>BYTE</tt>. For more information, refer to the description of <a href="dread.html"><tt>disk_read()</tt></a> function.</p>
<p>Generally, a multiple sector transfer request must not be split into single sector transactions to the storage device, or you will never get good write throughput.</p>
<p>FatFs expects delayed write feature of the disk functions. The write operation to the media need not to be completed due to write operation is in progress or only stored it into the cache buffer when return from this function. But data on the <tt class="arg">buff</tt> is invalid after return from this function. The write completion request is done by <tt>CTRL_SYNC</tt> command of <tt><a href="dioctl.html">disk_ioctl()</a></tt> function. Therefore, if delayed write feature is implemented, the write throughput may be improved.</p>
<p><em>Application program MUST NOT call this function, or FAT structure on the volume can be collapsed.</em></p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>This function is not needed when <tt>_FS_READONLY == 1</tt>.</p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/dwrite.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - disk_write</title>
</head>
<body>
<div class="para func">
<h2>disk_write</h2>
<p>The disk_write writes sector(s) to the storage device.</p>
<pre>
DRESULT disk_write (
BYTE <span class="arg">drv</span>, <span class="c">/* [IN] Physical drive number */</span>
const BYTE* <span class="arg">buff</span>, <span class="c">/* [IN] Pointer to the data to be written */</span>
DWORD <span class="arg">sector</span>, <span class="c">/* [IN] Sector number to write from */</span>
UINT <span class="arg">count</span> <span class="c">/* [IN] Number of sectors to write */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>pdrv</dt>
<dd>Physical drive number to identify the target device.</dd>
<dt>buff</dt>
<dd>Pointer to the <em>byte array</em> to be written. The size of data to be written is sector size * <tt class="arg">count</tt> bytes.</dd>
<dt>sector</dt>
<dd>Start sector number in logical block address (LBA).</dd>
<dt>count</dt>
<dd>Number of sectors to write. FatFs specifis it in range of from 1 to 128.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<dl class="ret">
<dt>RES_OK (0)</dt>
<dd>The function succeeded.</dd>
<dt>RES_ERROR</dt>
<dd>Any hard error occured during the write operation and could not recover it.</dd>
<dt>RES_WRPRT</dt>
<dd>The medium is write protected.</dd>
<dt>RES_PARERR</dt>
<dd>Invalid parameter.</dd>
<dt>RES_NOTRDY</dt>
<dd>The device has not been initialized.</dd>
</dl>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The specified memory address is not that always aligned to word boundary because the type of pointer is defined as <tt>BYTE*</tt>. For more information, refer to the description of <a href="dread.html"><tt>disk_read()</tt></a> function.</p>
<p>Generally, a multiple sector transfer request must not be split into single sector transactions to the storage device, or you will never get good write throughput.</p>
<p>FatFs expects delayed write feature of the disk functions. The write operation to the media need not to be completed due to write operation is in progress or only stored it into the cache buffer when return from this function. But data on the <tt class="arg">buff</tt> is invalid after return from this function. The write completion request is done by <tt>CTRL_SYNC</tt> command of <tt><a href="dioctl.html">disk_ioctl()</a></tt> function. Therefore, if delayed write feature is implemented, the write throughput may be improved.</p>
<p><em>Application program MUST NOT call this function, or FAT structure on the volume can be collapsed.</em></p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>This function is not needed when <tt>_FS_READONLY == 1</tt>.</p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,62 +1,62 @@
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<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/eof.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_eof</title>
</head>
<body>
<div class="para func">
<h2>f_eof</h2>
<p>The f_eof function tests for end-of-file on a file.</p>
<pre>
int f_eof (
FIL* <span class="arg">fp</span> <span class="c">/* [IN] File object */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>fp</dt>
<dd>Pointer to the open file object structure.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>The <tt>f_eof()</tt> function returns a non-zero value if the read/write pointer has reached end of the file; otherwise it returns a zero.</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>In this revision, this function is implemented as a macro.</p>
<pre>
<span class="k">#define</span> f_eof(fp) (((fp)->fptr) == ((fp)->fsize) ? 1 : 0)
</pre>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Always available.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a>, <a href="lseek.html">f_lseek</a>, <a href="sfile.html">FIL</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/eof.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_eof</title>
</head>
<body>
<div class="para func">
<h2>f_eof</h2>
<p>The f_eof function tests for end-of-file on a file.</p>
<pre>
int f_eof (
FIL* <span class="arg">fp</span> <span class="c">/* [IN] File object */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>fp</dt>
<dd>Pointer to the open file object structure.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>The <tt>f_eof()</tt> function returns a non-zero value if the read/write pointer has reached end of the file; otherwise it returns a zero.</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>In this revision, this function is implemented as a macro.</p>
<pre>
<span class="k">#define</span> f_eof(fp) (((fp)->fptr) == ((fp)->fsize) ? 1 : 0)
</pre>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Always available.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a>, <a href="lseek.html">f_lseek</a>, <a href="sfile.html">FIL</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,62 +1,62 @@
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<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/error.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_error</title>
</head>
<body>
<div class="para func">
<h2>f_error</h2>
<p>The f_error tests for an error on a file.</p>
<pre>
int f_error (
FIL* <span class="arg">fp</span> <span class="c">/* [IN] File object */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>fp</dt>
<dd>Pointer to the open file object structure.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>Returns a non-zero value if a hard error has occured; otherwise it returns a zero.</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>In this revision, this function is implemented as a macro.</p>
<pre>
<span class="k">#define</span> f_error(fp) (((fp)->flag & FA__ERROR) ? 1 : 0)
</pre>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Always available.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a>, <a href="sfile.html">FIL</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/error.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_error</title>
</head>
<body>
<div class="para func">
<h2>f_error</h2>
<p>The f_error tests for an error on a file.</p>
<pre>
int f_error (
FIL* <span class="arg">fp</span> <span class="c">/* [IN] File object */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>fp</dt>
<dd>Pointer to the open file object structure.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>Returns a non-zero value if a hard error has occured; otherwise it returns a zero.</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>In this revision, this function is implemented as a macro.</p>
<pre>
<span class="k">#define</span> f_error(fp) (((fp)->flag & FA__ERROR) ? 1 : 0)
</pre>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Always available.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a>, <a href="sfile.html">FIL</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,57 +1,57 @@
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<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/fattime.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - get_fattime</title>
</head>
<body>
<div class="para func">
<h2>get_fattime</h2>
<p>The get_fattime function gets current time.</p>
<pre>
DWORD get_fattime (void);
</pre>
</div>
<div class="para ret">
<h4>Return Value</h4>
<p>Currnet time is returned with packed into a <tt>DWORD</tt> value. The bit field is as follows:</p>
<dl class="ret">
<dt>bit31:25</dt>
<dd>Year origin from the 1980 (0..127)</dd>
<dt>bit24:21</dt>
<dd>Month (1..12)</dd>
<dt>bit20:16</dt>
<dd>Day of the month(1..31)</dd>
<dt>bit15:11</dt>
<dd>Hour (0..23)</dd>
<dt>bit10:5</dt>
<dd>Minute (0..59)</dd>
<dt>bit4:0</dt>
<dd>Second / 2 (0..29)</dd>
</dl>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>get_fattime()</tt> function shall return any valid time even if the system does not support a real time clock. If a zero is returned, the file will not have a valid timestamp.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>This function is not needed when <tt>_FS_READONLY == 1</tt>.</p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/fattime.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - get_fattime</title>
</head>
<body>
<div class="para func">
<h2>get_fattime</h2>
<p>The get_fattime function gets current time.</p>
<pre>
DWORD get_fattime (void);
</pre>
</div>
<div class="para ret">
<h4>Return Value</h4>
<p>Currnet time is returned with packed into a <tt>DWORD</tt> value. The bit field is as follows:</p>
<dl class="ret">
<dt>bit31:25</dt>
<dd>Year origin from the 1980 (0..127)</dd>
<dt>bit24:21</dt>
<dd>Month (1..12)</dd>
<dt>bit20:16</dt>
<dd>Day of the month(1..31)</dd>
<dt>bit15:11</dt>
<dd>Hour (0..23)</dd>
<dt>bit10:5</dt>
<dd>Minute (0..59)</dd>
<dt>bit4:0</dt>
<dd>Second / 2 (0..29)</dd>
</dl>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>get_fattime()</tt> function shall return any valid time even if the system does not support a real time clock. If a zero is returned, the file will not have a valid timestamp.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>This function is not needed when <tt>_FS_READONLY == 1</tt>.</p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,97 +1,97 @@
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<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/fdisk.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_fdisk</title>
</head>
<body>
<div class="para func">
<h2>f_fdisk</h2>
<p>The f_fdisk fucntion divides a physical drive.</p>
<pre>
FRESULT f_fdisk (
BYTE <span class="arg">pdrv</span>, <span class="c">/* [IN] Physical drive number */</span>
const DWORD <span class="arg">part[]</span>, <span class="c">/* [IN] Partition size */</span>
void* <span class="arg">work</span> <span class="c">/* [IN] Work area */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>pdrv</dt>
<dd>Specifies the <em>physical drive</em> to be divided.</dd>
<dt>part[]</dt>
<dd>Partition map table. It must have four items.</dd>
<dt>work</dt>
<dd>Pointer to the function work area. The size must be at least <tt>_MAX_SS</tt> bytes.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#wp">FR_WRITE_PROTECTED</a>,
<a href="rc.html#ip">FR_INVALID_PARAMETER</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_fdisk()</tt> function creates a partition table into the MBR of the physical drive. The partitioning rule is in generic FDISK format, so that it can create upto four primary partitions. Logical volumes in the extended partition is not supported. The <tt class="arg">part[]</tt> with four items specifies how to divide the physical drive. The first item specifies the size of first primary partition and fourth item specifies the fourth primary partition. If the value is less than or equal to 100, it specifies percentage of the partition in the entire disk space. If it is larger than 100, it specifies the partition size in unit of sector.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_READOLNY == 0</tt>, <tt>_USE_MKFS == 1</tt> and <tt>_MULTI_PARTITION == 1</tt>.</p>
</div>
<div class="para use">
<h4>Example</h4>
<pre>
<span class="c">/* Volume management table defined by user (required when _MULTI_PARTITION == 1) */</span>
PARTITION VolToPart[] = {
{0, 1}, <span class="c">/* Logical drive 0 ==> Physical drive 0, 1st partition */</span>
{0, 2}, <span class="c">/* Logical drive 1 ==> Physical drive 0, 2nd partition */</span>
{1, 0} <span class="c">/* Logical drive 2 ==> Physical drive 1, auto detection */</span>
};
</pre>
<pre>
<span class="c">/* Initialize a brand-new disk drive mapped to physical drive 0 */</span>
FATFS fs;
DWORD plist[] = {50, 50, 0, 0}; <span class="c">/* Divide drive into two partitions */</span>
BYTE work[_MAX_SS];
f_fdisk(0, plist, work); <span class="c">/* Divide physical drive 0 */</span>
f_mount(&amp;fs, "0:", 0); <span class="c">/* Register work area to the logical drive 0 */</span>
f_mkfs("0:", 0, 0); <span class="c">/* Create FAT volume on the logical drive 0. 2nd argument is ignored. */</span>
f_mount(0, "0:", 0); <span class="c">/* Unregister work area from the logical drive 0 */</span>
f_mount(&amp;fs, "1:", 0); <span class="c">/* Register a work area to the logical drive 1 */</span>
f_mkfs("1:", 0, 0); <span class="c">/* Create FAT volume on the logical drive 1. 2nd argument is ignored. */</span>
f_mount(0, "1:", 0); <span class="c">/* Unregister work area from the logical drive 1 */</span>
</pre>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><a href="filename.html#vol">Volume management</a>, <a href="mkfs.html"><tt>f_mkfs</tt></a></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/fdisk.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_fdisk</title>
</head>
<body>
<div class="para func">
<h2>f_fdisk</h2>
<p>The f_fdisk fucntion divides a physical drive.</p>
<pre>
FRESULT f_fdisk (
BYTE <span class="arg">pdrv</span>, <span class="c">/* [IN] Physical drive number */</span>
const DWORD <span class="arg">part[]</span>, <span class="c">/* [IN] Partition size */</span>
void* <span class="arg">work</span> <span class="c">/* [IN] Work area */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>pdrv</dt>
<dd>Specifies the <em>physical drive</em> to be divided.</dd>
<dt>part[]</dt>
<dd>Partition map table. It must have four items.</dd>
<dt>work</dt>
<dd>Pointer to the function work area. The size must be at least <tt>_MAX_SS</tt> bytes.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#wp">FR_WRITE_PROTECTED</a>,
<a href="rc.html#ip">FR_INVALID_PARAMETER</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_fdisk()</tt> function creates a partition table into the MBR of the physical drive. The partitioning rule is in generic FDISK format, so that it can create upto four primary partitions. Logical volumes in the extended partition is not supported. The <tt class="arg">part[]</tt> with four items specifies how to divide the physical drive. The first item specifies the size of first primary partition and fourth item specifies the fourth primary partition. If the value is less than or equal to 100, it specifies percentage of the partition in the entire disk space. If it is larger than 100, it specifies the partition size in unit of sector.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_READOLNY == 0</tt>, <tt>_USE_MKFS == 1</tt> and <tt>_MULTI_PARTITION == 1</tt>.</p>
</div>
<div class="para use">
<h4>Example</h4>
<pre>
<span class="c">/* Volume management table defined by user (required when _MULTI_PARTITION == 1) */</span>
PARTITION VolToPart[] = {
{0, 1}, <span class="c">/* Logical drive 0 ==> Physical drive 0, 1st partition */</span>
{0, 2}, <span class="c">/* Logical drive 1 ==> Physical drive 0, 2nd partition */</span>
{1, 0} <span class="c">/* Logical drive 2 ==> Physical drive 1, auto detection */</span>
};
</pre>
<pre>
<span class="c">/* Initialize a brand-new disk drive mapped to physical drive 0 */</span>
FATFS fs;
DWORD plist[] = {50, 50, 0, 0}; <span class="c">/* Divide drive into two partitions */</span>
BYTE work[_MAX_SS];
f_fdisk(0, plist, work); <span class="c">/* Divide physical drive 0 */</span>
f_mount(&amp;fs, "0:", 0); <span class="c">/* Register work area to the logical drive 0 */</span>
f_mkfs("0:", 0, 0); <span class="c">/* Create FAT volume on the logical drive 0. 2nd argument is ignored. */</span>
f_mount(0, "0:", 0); <span class="c">/* Unregister work area from the logical drive 0 */</span>
f_mount(&amp;fs, "1:", 0); <span class="c">/* Register a work area to the logical drive 1 */</span>
f_mkfs("1:", 0, 0); <span class="c">/* Create FAT volume on the logical drive 1. 2nd argument is ignored. */</span>
f_mount(0, "1:", 0); <span class="c">/* Unregister work area from the logical drive 1 */</span>
</pre>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><a href="filename.html#vol">Volume management</a>, <a href="mkfs.html"><tt>f_mkfs</tt></a></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,78 +1,78 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/filename.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - Path Names</title>
</head>
<body>
<h1>Path Names</h1>
<div class="para" id="nam">
<h3>Format of the path names</h3>
<p>The format of path name on the FatFs module is similer to the filename specs of DOS/Windos as follows:</p>
<pre>"[<em>drive</em>:][/]<em>directory</em>/<em>file</em>"</pre>
<p>The FatFs module supports long file name (LFN) and 8.3 format file name (SFN). The LFN can be used when LFN feature is enabled (<tt>_USE_LFN &gt; 0</tt>). The sub directories are separated with a \ or / in the same way as DOS/Windows API. Duplicated separators are skipped and ignored. Only a difference is that the logical drive is specified in a numeral with a colon. When drive number is omitted, the drive number is assumed as <em>default drive</em> (drive 0 or current drive).</p>
<p>Control characters (<tt>'\0'</tt> to <tt>'\x1F'</tt>) are recognized as end of the path name. Leading/embedded spaces in the path name are valid as a part of the name at LFN configuration but they are recognized as end of the path name at non-LFN configuration. Trailing spaces and dots are ignored.</p>
<p>In default configuration (<tt>_FS_RPATH == 0</tt>), it does not have a concept of current directory like OS oriented file system. All objects on the volume are always specified in full path name that follows from the root directory. Dot directory names are not allowed. Heading separator is ignored and it can be exist or omitted. The default drive is fixed to drive 0.</p>
<p>When relative path feature is enabled (<tt>_FS_RPATH == 1</tt>), specified path is followed from the root directory if a heading separator is exist. If not, it is followed from the current directory of the drive set with <a href="chdir.html">f_chdir</a> function. Dot names are also allowed for the path name. The default drive is the current drive set with <a href="chdrive.html">f_chdrive</a> function.</p>
<table class="lst2">
<tr><td>Path name</td><td>_FS_RPATH == 0</td><td>_FS_RPATH == 1</td></tr>
<tr class="lst3"><td>file.txt</td><td>A file in the root directory of the drive 0</td><td>A file in the current directory of the current drive</td></tr>
<tr><td>/file.txt</td><td>A file in the root directory of the drive 0</td><td>A file in the root directory of the current drive</td></tr>
<tr><td></td><td>The root directory of the drive 0</td><td>The current directory of the current drive</td></tr>
<tr><td>/</td><td>The root directory of the drive 0</td><td>The root directory of the current drive</td></tr>
<tr><td>2:</td><td>The root directory of the drive 2</td><td>The current directory of the drive 2</td></tr>
<tr><td>2:/</td><td>The root directory of the drive 2</td><td>The root directory of the drive 2</td></tr>
<tr><td>2:file.txt</td><td>A file in the root directory of the drive 2</td><td>A file in the current directory of the drive 2</td></tr>
<tr><td>../file.txt</td><td>Invalid name</td><td>A file in the parent directory</td></tr>
<tr><td>.</td><td>Invalid name</td><td>This directory</td></tr>
<tr><td>..</td><td>Invalid name</td><td>Parent directory of the current directory</td></tr>
<tr><td>dir1/..</td><td>Invalid name</td><td>The current directory</td></tr>
<tr><td>/..</td><td>Invalid name</td><td>The root directory (sticks the top level)</td></tr>
</table>
<p>When option <tt>_STR_VOLUME_ID</tt> is specified, also pre-defined strings can be used as drive identifier in the path name instead of a numeral.</p>
</div>
<p><br></p>
<div class="para" id="uni">
<h3>Unicode API</h3>
<p>The path names are input/output in either ANSI/OEM code (SBCS/DBCS) or Unicode depends on the configuration options. The type of arguments which specify the file names are defined as <tt>TCHAR</tt>. It is an alias of <tt>char</tt> in default. The code set used to the file name string is ANSI/OEM specifid by <tt>_CODE_PAGE</tt>. When <tt>_LFN_UNICODE</tt> is set to 1, the type of the <tt>TCHAR</tt> is switched to <tt>WCHAR</tt> to support Unicode (UTF-16 encoding). In this case, the LFN feature is fully supported and the Unicode specific characters, such as ✝☪✡☸☭, can also be used for the path name. It also affects data types and encoding of the string I/O functions. To define literal strings, <tt>_T(s)</tt> and <tt>_TEXT(s)</tt> macro are available to select either ANSI/OEM or Unicode automatically. The code shown below is an example to define the literal strings.</p>
<pre>
f_open(fp, "filename.txt", FA_READ); <span class="c">/* ANSI/OEM string */</span>
f_open(fp, L"filename.txt", FA_READ); <span class="c">/* Unicode string */</span>
f_open(fp, _T("filename.txt"), FA_READ); <span class="c">/* Changed by configuration */</span>
</pre>
</div>
<p><br></p>
<div class="para" id="vol">
<h3>Volume Management</h3>
<p>The FatFs module needs dynamic work area called <em>file system object</em> for each volume (logical drive). It is registered to the FatFs module by <tt>f_mount()</tt> function. By default, each logical drive is bound to the physical drive with the same drive number and an FAT volume on the drive is serched by auto detect feature. It loads boot sectors and checks it if it is an FAT boot sector in order of sector 0 as SFD format, 1st partition, 2nd partition, 3rd partition and 4th partition as FDISK format.</p>
<p>When <tt>_MULTI_PARTITION == 1</tt> is specified by configuration option, each individual logical drive is bound to the partition on the physical drive specified by volume management table. The volume management table must be defined by user to resolve relationship between logical drives and partitions. Following code is an example of a volume management table.</p>
<pre>
Example: Logical drive 0-2 are tied to three pri-partitions on the physical drive 0 (fixed disk)
Logical drive 3 is tied to an FAT volume on the physical drive 1 (removable disk)
PARTITION VolToPart[] = {
{0, 1}, <span class="c">/* Logical drive 0 ==> Physical drive 0, 1st partition */</span>
{0, 2}, <span class="c">/* Logical drive 1 ==> Physical drive 0, 2nd partition */</span>
{0, 3}, <span class="c">/* Logical drive 2 ==> Physical drive 0, 3rd partition */</span>
{1, 0} <span class="c">/* Logical drive 3 ==> Physical drive 1 (auto detection) */</span>
};
<img src="../img/f7.png" width="828" height="288" alt="relationship between logical drive and physical drive">
</pre>
<p>There are some considerations on using <tt>_MULTI_PARTITION</tt> configuration.</p>
<ul>
<li>Only four primary partitions can be specified. Logical partition is not supported.</li>
<li>The physical drive that has two or more mounted partitions must be non-removable. Media change while a system operation is prohibited.</li>
</ul>
</div>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/filename.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - Path Names</title>
</head>
<body>
<h1>Path Names</h1>
<div class="para" id="nam">
<h3>Format of the path names</h3>
<p>The format of path name on the FatFs module is similer to the filename specs of DOS/Windos as follows:</p>
<pre>"[<em>drive</em>:][/]<em>directory</em>/<em>file</em>"</pre>
<p>The FatFs module supports long file name (LFN) and 8.3 format file name (SFN). The LFN can be used when LFN feature is enabled (<tt>_USE_LFN &gt; 0</tt>). The sub directories are separated with a \ or / in the same way as DOS/Windows API. Duplicated separators are skipped and ignored. Only a difference is that the logical drive is specified in a numeral with a colon. When drive number is omitted, the drive number is assumed as <em>default drive</em> (drive 0 or current drive).</p>
<p>Control characters (<tt>'\0'</tt> to <tt>'\x1F'</tt>) are recognized as end of the path name. Leading/embedded spaces in the path name are valid as a part of the name at LFN configuration but they are recognized as end of the path name at non-LFN configuration. Trailing spaces and dots are ignored.</p>
<p>In default configuration (<tt>_FS_RPATH == 0</tt>), it does not have a concept of current directory like OS oriented file system. All objects on the volume are always specified in full path name that follows from the root directory. Dot directory names are not allowed. Heading separator is ignored and it can be exist or omitted. The default drive is fixed to drive 0.</p>
<p>When relative path feature is enabled (<tt>_FS_RPATH == 1</tt>), specified path is followed from the root directory if a heading separator is exist. If not, it is followed from the current directory of the drive set with <a href="chdir.html">f_chdir</a> function. Dot names are also allowed for the path name. The default drive is the current drive set with <a href="chdrive.html">f_chdrive</a> function.</p>
<table class="lst2">
<tr><td>Path name</td><td>_FS_RPATH == 0</td><td>_FS_RPATH == 1</td></tr>
<tr class="lst3"><td>file.txt</td><td>A file in the root directory of the drive 0</td><td>A file in the current directory of the current drive</td></tr>
<tr><td>/file.txt</td><td>A file in the root directory of the drive 0</td><td>A file in the root directory of the current drive</td></tr>
<tr><td></td><td>The root directory of the drive 0</td><td>The current directory of the current drive</td></tr>
<tr><td>/</td><td>The root directory of the drive 0</td><td>The root directory of the current drive</td></tr>
<tr><td>2:</td><td>The root directory of the drive 2</td><td>The current directory of the drive 2</td></tr>
<tr><td>2:/</td><td>The root directory of the drive 2</td><td>The root directory of the drive 2</td></tr>
<tr><td>2:file.txt</td><td>A file in the root directory of the drive 2</td><td>A file in the current directory of the drive 2</td></tr>
<tr><td>../file.txt</td><td>Invalid name</td><td>A file in the parent directory</td></tr>
<tr><td>.</td><td>Invalid name</td><td>This directory</td></tr>
<tr><td>..</td><td>Invalid name</td><td>Parent directory of the current directory</td></tr>
<tr><td>dir1/..</td><td>Invalid name</td><td>The current directory</td></tr>
<tr><td>/..</td><td>Invalid name</td><td>The root directory (sticks the top level)</td></tr>
</table>
<p>When option <tt>_STR_VOLUME_ID</tt> is specified, also pre-defined strings can be used as drive identifier in the path name instead of a numeral.</p>
</div>
<p><br></p>
<div class="para" id="uni">
<h3>Unicode API</h3>
<p>The path names are input/output in either ANSI/OEM code (SBCS/DBCS) or Unicode depends on the configuration options. The type of arguments which specify the file names are defined as <tt>TCHAR</tt>. It is an alias of <tt>char</tt> in default. The code set used to the file name string is ANSI/OEM specifid by <tt>_CODE_PAGE</tt>. When <tt>_LFN_UNICODE</tt> is set to 1, the type of the <tt>TCHAR</tt> is switched to <tt>WCHAR</tt> to support Unicode (UTF-16 encoding). In this case, the LFN feature is fully supported and the Unicode specific characters, such as ✝☪✡☸☭, can also be used for the path name. It also affects data types and encoding of the string I/O functions. To define literal strings, <tt>_T(s)</tt> and <tt>_TEXT(s)</tt> macro are available to select either ANSI/OEM or Unicode automatically. The code shown below is an example to define the literal strings.</p>
<pre>
f_open(fp, "filename.txt", FA_READ); <span class="c">/* ANSI/OEM string */</span>
f_open(fp, L"filename.txt", FA_READ); <span class="c">/* Unicode string */</span>
f_open(fp, _T("filename.txt"), FA_READ); <span class="c">/* Changed by configuration */</span>
</pre>
</div>
<p><br></p>
<div class="para" id="vol">
<h3>Volume Management</h3>
<p>The FatFs module needs dynamic work area called <em>file system object</em> for each volume (logical drive). It is registered to the FatFs module by <tt>f_mount()</tt> function. By default, each logical drive is bound to the physical drive with the same drive number and an FAT volume on the drive is serched by auto detect feature. It loads boot sectors and checks it if it is an FAT boot sector in order of sector 0 as SFD format, 1st partition, 2nd partition, 3rd partition and 4th partition as FDISK format.</p>
<p>When <tt>_MULTI_PARTITION == 1</tt> is specified by configuration option, each individual logical drive is bound to the partition on the physical drive specified by volume management table. The volume management table must be defined by user to resolve relationship between logical drives and partitions. Following code is an example of a volume management table.</p>
<pre>
Example: Logical drive 0-2 are tied to three pri-partitions on the physical drive 0 (fixed disk)
Logical drive 3 is tied to an FAT volume on the physical drive 1 (removable disk)
PARTITION VolToPart[] = {
{0, 1}, <span class="c">/* Logical drive 0 ==> Physical drive 0, 1st partition */</span>
{0, 2}, <span class="c">/* Logical drive 1 ==> Physical drive 0, 2nd partition */</span>
{0, 3}, <span class="c">/* Logical drive 2 ==> Physical drive 0, 3rd partition */</span>
{1, 0} <span class="c">/* Logical drive 3 ==> Physical drive 1 (auto detection) */</span>
};
<img src="../img/f7.png" width="828" height="288" alt="relationship between logical drive and physical drive">
</pre>
<p>There are some considerations on using <tt>_MULTI_PARTITION</tt> configuration.</p>
<ul>
<li>Only four primary partitions can be specified. Logical partition is not supported.</li>
<li>The physical drive that has two or more mounted partitions must be non-removable. Media change while a system operation is prohibited.</li>
</ul>
</div>
</body>
</html>

View file

@ -1,139 +1,139 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/forward.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_forward</title>
</head>
<body>
<div class="para func">
<h2>f_forward</h2>
<p>The f_forward function reads the file data and forward it to the data streaming device.</p>
<pre>
FRESULT f_forward (
FIL* <span class="arg">fp</span>, <span class="c">/* [IN] File object */</span>
UINT (*<span class="arg">func</span>)(const BYTE*,UINT), <span class="c">/* [IN] Data streaming function */</span>
UINT <span class="arg">btf</span>, <span class="c">/* [IN] Number of bytes to forward */</span>
UINT* <span class="arg">bf</span> <span class="c">/* [OUT] Number of bytes forwarded */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>fp</dt>
<dd>Pointer to the open file object.</dd>
<dt>func</dt>
<dd>Pointer to the user-defined data streaming function. For details, refer to the sample code.</dd>
<dt>btf</dt>
<dd>Number of bytes to forward in range of <tt>UINT</tt>.</dd>
<dt>bf</dt>
<dd>Pointer to the <tt>UINT</tt> variable to return number of bytes forwarded.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#io">FR_INVALID_OBJECT</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_forward()</tt> function reads the data from the file and forward it to the outgoing stream without data buffer. This is suitable for small memory system because it does not require any data buffer at application module. The file pointer of the file object increases in number of bytes forwarded. In case of <tt class="arg">*bf</tt> is less than <tt class="arg">btf</tt> without error, it means the requested bytes could not be transferred due to end of file or stream goes busy during data transfer.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_USE_FORWARD == 1</tt> and <tt>_FS_TINY == 1</tt>.</p>
</div>
<div class="para use">
<h4>Example (Audio playback)</h4>
<pre>
<span class="c">/*------------------------------------------------------------------------*/</span>
<span class="c">/* Sample code of data transfer function to be called back from f_forward */</span>
<span class="c">/*------------------------------------------------------------------------*/</span>
UINT out_stream ( <span class="c">/* Returns number of bytes sent or stream status */</span>
const BYTE *p, <span class="c">/* Pointer to the data block to be sent */</span>
UINT btf <span class="c">/* &gt;0: Transfer call (Number of bytes to be sent). 0: Sense call */</span>
)
{
UINT cnt = 0;
if (btf == 0) { <span class="c">/* Sense call */</span>
<span class="c">/* Return stream status (0: Busy, 1: Ready) */</span>
<span class="c">/* When once it returned ready to sense call, it must accept a byte at least */</span>
<span class="c">/* at subsequent transfer call, or f_forward will fail with FR_INT_ERR. */</span>
if (FIFO_READY) cnt = 1;
}
else { <span class="c">/* Transfer call */</span>
do { <span class="c">/* Repeat while there is any data to be sent and the stream is ready */</span>
FIFO_PORT = *p++;
cnt++;
} while (cnt &lt; btf &amp;&amp; FIFO_READY);
}
return cnt;
}
<span class="c">/*------------------------------------------------------------------------*/</span>
<span class="c">/* Sample code using f_forward function */</span>
<span class="c">/*------------------------------------------------------------------------*/</span>
FRESULT play_file (
char *fn <span class="c">/* Pointer to the audio file name to be played */</span>
)
{
FRESULT rc;
FIL fil;
UINT dmy;
<span class="c">/* Open the audio file in read only mode */</span>
rc = f_open(&amp;fil, fn, FA_READ);
if (rc) return rc;
<span class="c">/* Repeat until the file pointer reaches end of the file */</span>
while (rc == FR_OK &amp;&amp; fil.fptr &lt; fil.fsize) {
<span class="c">/* any other processes... */</span>
<span class="c">/* Fill output stream periodicaly or on-demand */</span>
rc = f_forward(&amp;fil, out_stream, 1000, &amp;dmy);
}
<span class="c">/* Close the file and return */</span>
f_close(&amp;fil);
return rc;
}
</pre>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a>, <a href="gets.html">fgets</a>, <a href="write.html">f_write</a>, <a href="close.html">f_close</a>, <a href="sfile.html">FIL</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/forward.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_forward</title>
</head>
<body>
<div class="para func">
<h2>f_forward</h2>
<p>The f_forward function reads the file data and forward it to the data streaming device.</p>
<pre>
FRESULT f_forward (
FIL* <span class="arg">fp</span>, <span class="c">/* [IN] File object */</span>
UINT (*<span class="arg">func</span>)(const BYTE*,UINT), <span class="c">/* [IN] Data streaming function */</span>
UINT <span class="arg">btf</span>, <span class="c">/* [IN] Number of bytes to forward */</span>
UINT* <span class="arg">bf</span> <span class="c">/* [OUT] Number of bytes forwarded */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>fp</dt>
<dd>Pointer to the open file object.</dd>
<dt>func</dt>
<dd>Pointer to the user-defined data streaming function. For details, refer to the sample code.</dd>
<dt>btf</dt>
<dd>Number of bytes to forward in range of <tt>UINT</tt>.</dd>
<dt>bf</dt>
<dd>Pointer to the <tt>UINT</tt> variable to return number of bytes forwarded.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#io">FR_INVALID_OBJECT</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_forward()</tt> function reads the data from the file and forward it to the outgoing stream without data buffer. This is suitable for small memory system because it does not require any data buffer at application module. The file pointer of the file object increases in number of bytes forwarded. In case of <tt class="arg">*bf</tt> is less than <tt class="arg">btf</tt> without error, it means the requested bytes could not be transferred due to end of file or stream goes busy during data transfer.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_USE_FORWARD == 1</tt> and <tt>_FS_TINY == 1</tt>.</p>
</div>
<div class="para use">
<h4>Example (Audio playback)</h4>
<pre>
<span class="c">/*------------------------------------------------------------------------*/</span>
<span class="c">/* Sample code of data transfer function to be called back from f_forward */</span>
<span class="c">/*------------------------------------------------------------------------*/</span>
UINT out_stream ( <span class="c">/* Returns number of bytes sent or stream status */</span>
const BYTE *p, <span class="c">/* Pointer to the data block to be sent */</span>
UINT btf <span class="c">/* &gt;0: Transfer call (Number of bytes to be sent). 0: Sense call */</span>
)
{
UINT cnt = 0;
if (btf == 0) { <span class="c">/* Sense call */</span>
<span class="c">/* Return stream status (0: Busy, 1: Ready) */</span>
<span class="c">/* When once it returned ready to sense call, it must accept a byte at least */</span>
<span class="c">/* at subsequent transfer call, or f_forward will fail with FR_INT_ERR. */</span>
if (FIFO_READY) cnt = 1;
}
else { <span class="c">/* Transfer call */</span>
do { <span class="c">/* Repeat while there is any data to be sent and the stream is ready */</span>
FIFO_PORT = *p++;
cnt++;
} while (cnt &lt; btf &amp;&amp; FIFO_READY);
}
return cnt;
}
<span class="c">/*------------------------------------------------------------------------*/</span>
<span class="c">/* Sample code using f_forward function */</span>
<span class="c">/*------------------------------------------------------------------------*/</span>
FRESULT play_file (
char *fn <span class="c">/* Pointer to the audio file name to be played */</span>
)
{
FRESULT rc;
FIL fil;
UINT dmy;
<span class="c">/* Open the audio file in read only mode */</span>
rc = f_open(&amp;fil, fn, FA_READ);
if (rc) return rc;
<span class="c">/* Repeat until the file pointer reaches end of the file */</span>
while (rc == FR_OK &amp;&amp; fil.fptr &lt; fil.fsize) {
<span class="c">/* any other processes... */</span>
<span class="c">/* Fill output stream periodicaly or on-demand */</span>
rc = f_forward(&amp;fil, out_stream, 1000, &amp;dmy);
}
<span class="c">/* Close the file and return */</span>
f_close(&amp;fil);
return rc;
}
</pre>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a>, <a href="gets.html">fgets</a>, <a href="write.html">f_write</a>, <a href="close.html">f_close</a>, <a href="sfile.html">FIL</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,70 +1,70 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/getcwd.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_getcwd</title>
</head>
<body>
<div class="para func">
<h2>f_getcwd</h2>
<p>The f_getcwd function retrieves the current directory.</p>
<pre>
FRESULT f_getcwd (
TCHAR* <span class="arg">buff</span>, <span class="c">/* [OUT] Buffer to return path name */</span>
UINT <span class="arg">len</span> <span class="c">/* [IN] The length of the buffer */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>buff</dt>
<dd>Pointer to the buffer to receive the current directory string.</dd>
<dt>len</dt>
<dd>Size of the buffer in unit of TCHAR.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#ne">FR_NOT_ENABLED</a>,
<a href="rc.html#ns">FR_NO_FILESYSTEM</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>,
<a href="rc.html#nc">FR_NOT_ENOUGH_CORE</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_getcwd()</tt> function retrieves full path name of the current directory of the current drive. When <tt>_VOLUMES</tt> is larger than 1, a logical drive number is added to top of the path name.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_RPATH == 2</tt>.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="chdrive.html">f_chdrive</a>, <a href="chdir.html">f_chdir</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/getcwd.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_getcwd</title>
</head>
<body>
<div class="para func">
<h2>f_getcwd</h2>
<p>The f_getcwd function retrieves the current directory.</p>
<pre>
FRESULT f_getcwd (
TCHAR* <span class="arg">buff</span>, <span class="c">/* [OUT] Buffer to return path name */</span>
UINT <span class="arg">len</span> <span class="c">/* [IN] The length of the buffer */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>buff</dt>
<dd>Pointer to the buffer to receive the current directory string.</dd>
<dt>len</dt>
<dd>Size of the buffer in unit of TCHAR.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#ne">FR_NOT_ENABLED</a>,
<a href="rc.html#ns">FR_NO_FILESYSTEM</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>,
<a href="rc.html#nc">FR_NOT_ENOUGH_CORE</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_getcwd()</tt> function retrieves full path name of the current directory of the current drive. When <tt>_VOLUMES</tt> is larger than 1, a logical drive number is added to top of the path name.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_RPATH == 2</tt>.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="chdrive.html">f_chdrive</a>, <a href="chdir.html">f_chdir</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,95 +1,95 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/getfree.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_getfree</title>
</head>
<body>
<div class="para func">
<h2>f_getfree</h2>
<p>The f_getfree function gets number of the free clusters on the volume.</p>
<pre>
FRESULT f_getfree (
const TCHAR* <span class="arg">path</span>, <span class="c">/* [IN] Logical drive number */</span>
DWORD* <span class="arg">nclst</span>, <span class="c">/* [OUT] Number of free clusters */</span>
FATFS** <span class="arg">fatfs</span> <span class="c">/* [OUT] Corresponding file system object */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>path</dt>
<dd>Pinter to the null-terminated string that specifies the <a href="filename.html">logical drive</a>. A null-string means the default drive.</dd>
<dt>nclst</dt>
<dd>Pointer to the <tt>DWORD</tt> variable to store number of free clusters.</dd>
<dt>fatfs</dt>
<dd>Pointer to pointer that to store a pointer to the corresponding file system object.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>,
<a href="rc.html#ne">FR_NOT_ENABLED</a>,
<a href="rc.html#ns">FR_NO_FILESYSTEM</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>
</p>
</div>
<div class="para desc">
<h4>Descriptions</h4>
<p>The <tt>f_getfree()</tt> function gets number of free clusters on the volume. The member <tt>csize</tt> in the file system object indicates number of sectors per cluster, so that the free space in unit of sector can be calcurated with this information. When FSINFO structure on the FAT32 volume is not in sync, this function can return an incorrect free cluster count. To avoid this problem, FatFs can be forced full FAT scan by <tt>_FS_NOFSINFO</tt> option.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_READONLY == 0</tt> and <tt>_FS_MINIMIZE == 0</tt>.</p>
</div>
<div class="para use">
<h4>Example</h4>
<pre>
FATFS *fs;
DWORD fre_clust, fre_sect, tot_sect;
<span class="c">/* Get volume information and free clusters of drive 1 */</span>
res = f_getfree("1:", &amp;fre_clust, &amp;fs);
if (res) die(res);
<span class="c">/* Get total sectors and free sectors */</span>
tot_sect = (fs->n_fatent - 2) * fs->csize;
fre_sect = fre_clust * fs->csize;
<span class="c">/* Print the free space (assuming 512 bytes/sector) */</span>
printf("%10lu KiB total drive space.\n%10lu KiB available.\n",
tot_sect / 2, fre_sect / 2);
</pre>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="sfatfs.html">FATFS</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/getfree.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_getfree</title>
</head>
<body>
<div class="para func">
<h2>f_getfree</h2>
<p>The f_getfree function gets number of the free clusters on the volume.</p>
<pre>
FRESULT f_getfree (
const TCHAR* <span class="arg">path</span>, <span class="c">/* [IN] Logical drive number */</span>
DWORD* <span class="arg">nclst</span>, <span class="c">/* [OUT] Number of free clusters */</span>
FATFS** <span class="arg">fatfs</span> <span class="c">/* [OUT] Corresponding file system object */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>path</dt>
<dd>Pinter to the null-terminated string that specifies the <a href="filename.html">logical drive</a>. A null-string means the default drive.</dd>
<dt>nclst</dt>
<dd>Pointer to the <tt>DWORD</tt> variable to store number of free clusters.</dd>
<dt>fatfs</dt>
<dd>Pointer to pointer that to store a pointer to the corresponding file system object.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>,
<a href="rc.html#ne">FR_NOT_ENABLED</a>,
<a href="rc.html#ns">FR_NO_FILESYSTEM</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>
</p>
</div>
<div class="para desc">
<h4>Descriptions</h4>
<p>The <tt>f_getfree()</tt> function gets number of free clusters on the volume. The member <tt>csize</tt> in the file system object indicates number of sectors per cluster, so that the free space in unit of sector can be calcurated with this information. When FSINFO structure on the FAT32 volume is not in sync, this function can return an incorrect free cluster count. To avoid this problem, FatFs can be forced full FAT scan by <tt>_FS_NOFSINFO</tt> option.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_READONLY == 0</tt> and <tt>_FS_MINIMIZE == 0</tt>.</p>
</div>
<div class="para use">
<h4>Example</h4>
<pre>
FATFS *fs;
DWORD fre_clust, fre_sect, tot_sect;
<span class="c">/* Get volume information and free clusters of drive 1 */</span>
res = f_getfree("1:", &amp;fre_clust, &amp;fs);
if (res) die(res);
<span class="c">/* Get total sectors and free sectors */</span>
tot_sect = (fs->n_fatent - 2) * fs->csize;
fre_sect = fre_clust * fs->csize;
<span class="c">/* Print the free space (assuming 512 bytes/sector) */</span>
printf("%10lu KiB total drive space.\n%10lu KiB available.\n",
tot_sect / 2, fre_sect / 2);
</pre>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="sfatfs.html">FATFS</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,82 +1,82 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/getlabel.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_getlabel</title>
</head>
<body>
<div class="para func">
<h2>f_getlabel</h2>
<p>The f_getlabel function returns volume label and volume serial number of a drive.</p>
<pre>
FRESULT f_getlabel (
const TCHAR* <span class="arg">path</span>, <span class="c">/* [IN] Drive number */</span>
TCHAR* <span class="arg">label</span>, <span class="c">/* [OUT] Volume label */</span>
DWORD* <span class="arg">vsn</span> <span class="c">/* [OUT] Volume serial number */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>path</dt>
<dd>Pointer to the null-terminated string that specifies the <a href="filename.html">logical drive</a>. Null-string specifies the default drive.</dd>
<dt>label</dt>
<dd>Pointer to the buffer to store the volume label. The buffer size must be at least 12 items. If the volume has no label, a null-string will be returned. Set null pointer if this information is not needed.</dd>
<dt>vsn</dt>
<dd>Pointer to the <tt>DWORD</tt> variable to store the volume serial number. Set null pointer if this information is not needed.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>,
<a href="rc.html#ne">FR_NOT_ENABLED</a>,
<a href="rc.html#ns">FR_NO_FILESYSTEM</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>
</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_USE_LABEL == 1</tt>.</p>
</div>
<div class="para use">
<h4>Example</h4>
<pre>
char str[12];
<span class="c">/* Get volume label of the default drive */</span>
f_getlabel("", str, 0);
<span class="c">/* Get volume label of the drive 2 */</span>
f_getlabel("2:", str, 0);
</pre>
</div>
<div class="para ref">
<h4>See Also</h4>
<tt><a href="setlabel.html">f_setlabel</a></tt>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/getlabel.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_getlabel</title>
</head>
<body>
<div class="para func">
<h2>f_getlabel</h2>
<p>The f_getlabel function returns volume label and volume serial number of a drive.</p>
<pre>
FRESULT f_getlabel (
const TCHAR* <span class="arg">path</span>, <span class="c">/* [IN] Drive number */</span>
TCHAR* <span class="arg">label</span>, <span class="c">/* [OUT] Volume label */</span>
DWORD* <span class="arg">vsn</span> <span class="c">/* [OUT] Volume serial number */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>path</dt>
<dd>Pointer to the null-terminated string that specifies the <a href="filename.html">logical drive</a>. Null-string specifies the default drive.</dd>
<dt>label</dt>
<dd>Pointer to the buffer to store the volume label. The buffer size must be at least 12 items. If the volume has no label, a null-string will be returned. Set null pointer if this information is not needed.</dd>
<dt>vsn</dt>
<dd>Pointer to the <tt>DWORD</tt> variable to store the volume serial number. Set null pointer if this information is not needed.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>,
<a href="rc.html#ne">FR_NOT_ENABLED</a>,
<a href="rc.html#ns">FR_NO_FILESYSTEM</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>
</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_USE_LABEL == 1</tt>.</p>
</div>
<div class="para use">
<h4>Example</h4>
<pre>
char str[12];
<span class="c">/* Get volume label of the default drive */</span>
f_getlabel("", str, 0);
<span class="c">/* Get volume label of the drive 2 */</span>
f_getlabel("2:", str, 0);
</pre>
</div>
<div class="para ref">
<h4>See Also</h4>
<tt><a href="setlabel.html">f_setlabel</a></tt>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,65 +1,65 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/gets.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_gets</title>
</head>
<body>
<div class="para func">
<h2>f_gets</h2>
<p>The f_gets reads a string from the file.</p>
<pre>
TCHAR* f_gets (
TCHAR* <span class="arg">buff</span>, <span class="c">/* [OUT] Read buffer */</span>
int <span class="arg">len</span>, <span class="c">/* [IN] Size of the read buffer */</span>
FIL* <span class="arg">fp</span> <span class="c">/* [IN] File object */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>buff</dt>
<dd>Pointer to read buffer to store the read string.</dd>
<dt>len</dt>
<dd>Size of the read buffer in unit of character.</dd>
<dt>fp</dt>
<dd>Pointer to the open file object structure.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>When the function succeeded, <tt class="arg">buff</tt> will be returuned.</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_gets()</tt> function is a wrapper function of <a href="read.html"><tt>f_read()</tt></a> function. The read operation continues until a <tt>'\n'</tt> is stored, reached end of the file or the buffer is filled with <tt>len - 1</tt> characters. The read string is terminated with a <tt>'\0'</tt>. When no character to read or any error occured during read operation, it returns a null pointer. The status of EOF and error can be examined with <tt>f_eof()</tt> and <tt>f_error()</tt> macros.</p>
<p>When FatFs is configured to Unicode API (<tt>_LFN_UNICODE == 1</tt>), data types on the srting fuctions, <tt>f_putc()</tt>, <tt>f_puts()</tt>, <tt>f_printf()</tt> and <tt>f_gets()</tt>, is also switched to Unicode. The character encoding on the file to be read/written via those functions is selected by <tt>_STRF_ENCODE</tt> option.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_USE_STRFUNC</tt> is 1 or 2. When it is set to 2, <tt>'\r'</tt>s contained in the file are stripped out.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a>, <a href="read.html">f_read</a>, <a href="putc.html">f_putc</a>, <a href="puts.html">f_puts</a>, <a href="printf.html">f_printf</a>, <a href="close.html">f_close</a>, <a href="sfile.html">FIL</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/gets.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_gets</title>
</head>
<body>
<div class="para func">
<h2>f_gets</h2>
<p>The f_gets reads a string from the file.</p>
<pre>
TCHAR* f_gets (
TCHAR* <span class="arg">buff</span>, <span class="c">/* [OUT] Read buffer */</span>
int <span class="arg">len</span>, <span class="c">/* [IN] Size of the read buffer */</span>
FIL* <span class="arg">fp</span> <span class="c">/* [IN] File object */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>buff</dt>
<dd>Pointer to read buffer to store the read string.</dd>
<dt>len</dt>
<dd>Size of the read buffer in unit of character.</dd>
<dt>fp</dt>
<dd>Pointer to the open file object structure.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>When the function succeeded, <tt class="arg">buff</tt> will be returuned.</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_gets()</tt> function is a wrapper function of <a href="read.html"><tt>f_read()</tt></a> function. The read operation continues until a <tt>'\n'</tt> is stored, reached end of the file or the buffer is filled with <tt>len - 1</tt> characters. The read string is terminated with a <tt>'\0'</tt>. When no character to read or any error occured during read operation, it returns a null pointer. The status of EOF and error can be examined with <tt>f_eof()</tt> and <tt>f_error()</tt> macros.</p>
<p>When FatFs is configured to Unicode API (<tt>_LFN_UNICODE == 1</tt>), data types on the srting fuctions, <tt>f_putc()</tt>, <tt>f_puts()</tt>, <tt>f_printf()</tt> and <tt>f_gets()</tt>, is also switched to Unicode. The character encoding on the file to be read/written via those functions is selected by <tt>_STRF_ENCODE</tt> option.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_USE_STRFUNC</tt> is 1 or 2. When it is set to 2, <tt>'\r'</tt>s contained in the file are stripped out.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a>, <a href="read.html">f_read</a>, <a href="putc.html">f_putc</a>, <a href="puts.html">f_puts</a>, <a href="printf.html">f_printf</a>, <a href="close.html">f_close</a>, <a href="sfile.html">FIL</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,129 +1,129 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/lseek.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_lseek</title>
</head>
<body>
<div class="para func">
<h2>f_lseek</h2>
<p>The f_lseek function moves the file read/write pointer of an open file object. It can also be used to expand the file size (cluster pre-allocation). </p>
<pre>
FRESULT f_lseek (
FIL* <span class="arg">fp</span>, <span class="c">/* [IN] File object */</span>
DWORD <span class="arg">ofs</span> <span class="c">/* [IN] File read/write pointer */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>fp</dt>
<dd>Pointer to the open file object.</dd>
<dt>ofs</dt>
<dd>Byte offset from top of the file.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#io">FR_INVALID_OBJECT</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_lseek()</tt> function moves the file read/write pointer of an open file. The offset can be specified in only origin from top of the file. When an offset beyond the file size is specified in write mode, the file size is expanded to the specified offset. The file data in the expanded area is undefined because no data is written to the file. This is suitable to pre-allocate a cluster chain quickly, for fast write operation. After the <tt>f_lseek()</tt> function succeeded, the current read/write pointer should be checked in order to make sure the read/write pointer has been moved correctry. In case of the current read/write pointer is not the expected value, either of followings has been occured.</p>
<ul>
<li>End of file. The specified <tt class="arg">ofs</tt> was clipped at end of the file because the file has been opened in read-only mode.</li>
<li>Disk full. There is insufficient free space on the volume to expand the file.</li>
</ul>
<p>Fast seek feature is enabled when <tt>_USE_FASTSEEK</tt> is set to 1 and the member <tt>cltbl</tt> in the file object is not NULL. This feature enables fast backward/long seek operations without FAT access by using CLMT (cluster link map table). The fast seek feature is also applied to <tt>f_read()/f_write()</tt> function, however, the file size cannot be expanded by <tt>f_write()/f_lseek()</tt> function.</p>
<p>The CLMT must be created in the user defined <tt>DWORD</tt> array prior to use the fast seek feature. To create the CLMT, set address of the <tt>DWORD</tt> array to the member <tt>cltbl</tt> in the file object, set the array size in unit of items into the first item and call the <tt>f_lseek()</tt> function with <tt class="arg">ofs</tt><tt> = CREATE_LINKMAP</tt>. After the function succeeded and CLMT is created, no FAT access is occured at subsequent <tt>f_read()/f_write()/f_lseek()</tt> function to the file. If the function failed with <tt>FR_NOT_ENOUGH_CORE</tt>, the given array size is insufficient for the file and number of items required is returned into the first item of the array. The required array size is (number of fragments + 1) * 2 items. For example, when the file is fragmented in 5, 12 items will be required for the CLMT.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_MINIMIZE &lt;= 2</tt>.</p>
</div>
<div class="para use">
<h4>Example</h4>
<pre>
<span class="c">/* Open file */</span>
fp = malloc(sizeof (FIL));
res = f_open(fp, "file.dat", FA_READ|FA_WRITE);
if (res) ...
<span class="c">/* Move to offset of 5000 from top of the file */</span>
res = f_lseek(fp, 5000);
<span class="c">/* Move to end of the file to append data */</span>
res = f_lseek(fp, f_size(fp));
<span class="c">/* Forward 3000 bytes */</span>
res = f_lseek(fp, f_tell(fp) + 3000);
<span class="c">/* Rewind 2000 bytes (take care on wraparound) */</span>
res = f_lseek(fp, f_tell(fp) - 2000);
</pre>
<pre>
<span class="c">/* Cluster pre-allocation (to prevent buffer overrun on streaming write) */</span>
res = f_open(fp, recfile, FA_CREATE_NEW | FA_WRITE); <span class="c">/* Create a file */</span>
res = f_lseek(fp, PRE_SIZE); <span class="c">/* Expand file size (cluster pre-allocation) */</span>
if (res || f_tell(fp) != PRE_SIZE) ... <span class="c">/* Check if the file has been expanded */</span>
res = f_lseek(fp, DATA_START); <span class="c">/* Record data stream WITHOUT cluster allocation delay */</span>
... <span class="c">/* DATA_START and write block size should be aligned to sector boundary */</span>
res = f_truncate(fp); <span class="c">/* Truncate unused area */</span>
res = f_lseek(fp, 0); <span class="c">/* Put file header */</span>
...
res = f_close(fp);
</pre>
<pre>
<span class="c">/* Using fast seek feature */</span>
DWORD clmt[SZ_TBL]; <span class="c">/* Cluster link map table buffer */</span>
res = f_lseek(fp, ofs1); <span class="c">/* This is normal seek (cltbl is nulled on file open) */</span>
fp-&gt;cltbl = clmt; <span class="c">/* Enable fast seek feature (cltbl != NULL) */</span>
clmt[0] = SZ_TBL; <span class="c">/* Set table size */</span>
res = f_lseek(fp, CREATE_LINKMAP); <span class="c">/* Create CLMT */</span>
...
res = f_lseek(fp, ofs2); <span class="c">/* This is fast seek */</span>
</pre>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a>, <a href="truncate.html">f_truncate</a>, <a href="sfile.html">FIL</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/lseek.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_lseek</title>
</head>
<body>
<div class="para func">
<h2>f_lseek</h2>
<p>The f_lseek function moves the file read/write pointer of an open file object. It can also be used to expand the file size (cluster pre-allocation). </p>
<pre>
FRESULT f_lseek (
FIL* <span class="arg">fp</span>, <span class="c">/* [IN] File object */</span>
DWORD <span class="arg">ofs</span> <span class="c">/* [IN] File read/write pointer */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>fp</dt>
<dd>Pointer to the open file object.</dd>
<dt>ofs</dt>
<dd>Byte offset from top of the file.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#io">FR_INVALID_OBJECT</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_lseek()</tt> function moves the file read/write pointer of an open file. The offset can be specified in only origin from top of the file. When an offset beyond the file size is specified at write mode, the file size is expanded to the specified offset. The file data in the expanded area is undefined because no data is written to the file. This is suitable to pre-allocate a cluster chain quickly, for fast write operation. After the <tt>f_lseek()</tt> function succeeded, the current read/write pointer should be checked in order to make sure the read/write pointer has been moved correctry. In case of the current read/write pointer is not the expected value, either of followings has been occured.</p>
<ul>
<li>End of file. The specified <tt class="arg">ofs</tt> was clipped at end of the file because the file has been opened in read-only mode.</li>
<li>Disk full. There is insufficient free space on the volume to expand the file.</li>
</ul>
<p>Fast seek feature is enabled when <tt>_USE_FASTSEEK</tt> is set to 1 and the member <tt>cltbl</tt> in the file object is not NULL. This feature enables fast backward/long seek operations without FAT access by using CLMT (cluster link map table). The fast seek feature is also applied to <tt>f_read()/f_write()</tt> function, however, the file size cannot be expanded by <tt>f_write()/f_lseek()</tt> function.</p>
<p>The CLMT must be created in the user defined <tt>DWORD</tt> array prior to use the fast seek feature. To create the CLMT, set address of the <tt>DWORD</tt> array to the member <tt>cltbl</tt> in the file object, set the array size in unit of items into the first item and call the <tt>f_lseek()</tt> function with <tt class="arg">ofs</tt><tt> = CREATE_LINKMAP</tt>. After the function succeeded and CLMT is created, no FAT access is occured at subsequent <tt>f_read()/f_write()/f_lseek()</tt> function to the file. If the function failed with <tt>FR_NOT_ENOUGH_CORE</tt>, the given array size is insufficient for the file and number of items required is returned into the first item of the array. The required array size is (number of fragments + 1) * 2 items. For example, when the file is fragmented in 5, 12 items will be required for the CLMT.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_MINIMIZE &lt;= 2</tt>.</p>
</div>
<div class="para use">
<h4>Example</h4>
<pre>
<span class="c">/* Open file */</span>
fp = malloc(sizeof (FIL));
res = f_open(fp, "file.dat", FA_READ|FA_WRITE);
if (res) ...
<span class="c">/* Move to offset of 5000 from top of the file */</span>
res = f_lseek(fp, 5000);
<span class="c">/* Move to end of the file to append data */</span>
res = f_lseek(fp, f_size(fp));
<span class="c">/* Forward 3000 bytes */</span>
res = f_lseek(fp, f_tell(fp) + 3000);
<span class="c">/* Rewind 2000 bytes (take care on wraparound) */</span>
res = f_lseek(fp, f_tell(fp) - 2000);
</pre>
<pre>
<span class="c">/* Cluster pre-allocation (to prevent buffer overrun on streaming write) */</span>
res = f_open(fp, recfile, FA_CREATE_NEW | FA_WRITE); <span class="c">/* Create a file */</span>
res = f_lseek(fp, PRE_SIZE); <span class="c">/* Expand file size (cluster pre-allocation) */</span>
if (res || f_tell(fp) != PRE_SIZE) ... <span class="c">/* Check if the file has been expanded */</span>
res = f_lseek(fp, DATA_START); <span class="c">/* Record data stream WITHOUT cluster allocation delay */</span>
... <span class="c">/* DATA_START and write block size should be aligned to sector boundary */</span>
res = f_truncate(fp); <span class="c">/* Truncate unused area */</span>
res = f_lseek(fp, 0); <span class="c">/* Put file header */</span>
...
res = f_close(fp);
</pre>
<pre>
<span class="c">/* Using fast seek feature */</span>
DWORD clmt[SZ_TBL]; <span class="c">/* Cluster link map table buffer */</span>
res = f_lseek(fp, ofs1); <span class="c">/* This is normal seek (cltbl is nulled on file open) */</span>
fp-&gt;cltbl = clmt; <span class="c">/* Enable fast seek feature (cltbl != NULL) */</span>
clmt[0] = SZ_TBL; <span class="c">/* Set table size */</span>
res = f_lseek(fp, CREATE_LINKMAP); <span class="c">/* Create CLMT */</span>
...
res = f_lseek(fp, ofs2); <span class="c">/* This is fast seek */</span>
</pre>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a>, <a href="truncate.html">f_truncate</a>, <a href="sfile.html">FIL</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,80 +1,80 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/mkdir.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_mkdir</title>
</head>
<body>
<div class="para func">
<h2>f_mkdir</h2>
<p>The f_mkdir function creates a new directory.</p>
<pre>
FRESULT f_mkdir (
const TCHAR* <span class="arg">path</span> <span class="c">/* [IN] Directory name */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameter</h4>
<dl class="par">
<dt>path</dt>
<dd>Pointer to the null-terminated string that specifies the <a href="filename.html">directory name</a> to create. </dd>
</dl>
</div>
<div class="para ret">
<h4>Return Value</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#np">FR_NO_PATH</a>,
<a href="rc.html#in">FR_INVALID_NAME</a>,
<a href="rc.html#de">FR_DENIED</a>,
<a href="rc.html#ex">FR_EXIST</a>,
<a href="rc.html#wp">FR_WRITE_PROTECTED</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>,
<a href="rc.html#ne">FR_NOT_ENABLED</a>,
<a href="rc.html#ns">FR_NO_FILESYSTEM</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>,
<a href="rc.html#nc">FR_NOT_ENOUGH_CORE</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>This function creates a new directory.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_READONLY == 0</tt> and <tt>_FS_MINIMIZE == 0</tt>.</p>
</div>
<div class="para use">
<h4>Example</h4>
<pre>
res = f_mkdir("sub1");
if (res) die(res);
res = f_mkdir("sub1/sub2");
if (res) die(res);
res = f_mkdir("sub1/sub2/sub3");
if (res) die(res);
</pre>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/mkdir.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_mkdir</title>
</head>
<body>
<div class="para func">
<h2>f_mkdir</h2>
<p>The f_mkdir function creates a new directory.</p>
<pre>
FRESULT f_mkdir (
const TCHAR* <span class="arg">path</span> <span class="c">/* [IN] Directory name */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameter</h4>
<dl class="par">
<dt>path</dt>
<dd>Pointer to the null-terminated string that specifies the <a href="filename.html">directory name</a> to create. </dd>
</dl>
</div>
<div class="para ret">
<h4>Return Value</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#np">FR_NO_PATH</a>,
<a href="rc.html#in">FR_INVALID_NAME</a>,
<a href="rc.html#de">FR_DENIED</a>,
<a href="rc.html#ex">FR_EXIST</a>,
<a href="rc.html#wp">FR_WRITE_PROTECTED</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>,
<a href="rc.html#ne">FR_NOT_ENABLED</a>,
<a href="rc.html#ns">FR_NO_FILESYSTEM</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>,
<a href="rc.html#nc">FR_NOT_ENOUGH_CORE</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>This function creates a new directory.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_READONLY == 0</tt> and <tt>_FS_MINIMIZE == 0</tt>.</p>
</div>
<div class="para use">
<h4>Example</h4>
<pre>
res = f_mkdir("sub1");
if (res) die(res);
res = f_mkdir("sub1/sub2");
if (res) die(res);
res = f_mkdir("sub1/sub2/sub3");
if (res) die(res);
</pre>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,73 +1,73 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/mkfs.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_mkfs</title>
</head>
<body>
<div class="para func">
<h2>f_mkfs</h2>
<p>The f_mkfs fucntion creates an FAT file system on the logical drive.</p>
<pre>
FRESULT f_mkfs (
const TCHAR* <span class="arg">path</span>, <span class="c">/* [IN] Logical drive number */</span>
BYTE <span class="arg">sfd</span>, <span class="c">/* [IN] Partitioning rule */</span>
UINT <span class="arg">au</span> <span class="c">/* [IN] Size of the allocation unit */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>path</dt>
<dd>Pinter to the null-terminated string that specifies the <a href="filename.html">logical drive</a> to be formatted. If there is no drive number, it means the default drive.</dd>
<dt>sfd</dt>
<dd>Specifies partitioning rule (FDISK(0) or SFD(1)). This argument will be ignored on some case.</dd>
<dt>au</dt>
<dd>Specifies size of the allocation unit (cluter) in unit of byte. The value must be sector size * n (n is 1 to 128 and power of 2). When a zero is given, the cluster size is determined depends on the volume size.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#wp">FR_WRITE_PROTECTED</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>,
<a href="rc.html#ne">FR_NOT_ENABLED</a>,
<a href="rc.html#ma">FR_MKFS_ABORTED</a>,
<a href="rc.html#ip">FR_INVALID_PARAMETER</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_mkfs()</tt> function creates an FAT volume on the logical drive. When FDISK format is specified, a primary partition occupies the entire disk space is created and then an FAT volume is created on the partition. When SFD format is specified, the FAT volume starts from the first sector of the physical drive.</p>
<p>If the logical drive has been bound to any partition (1-4) by multiple partition feature (<tt>_MULTI_PARTITION</tt>), the FAT volume is created into the specified partition. In this case, the second argument <tt class="arg">sfd</tt> is ignored. The physical drive must have been partitioned with <tt>f_fdisk()</tt> function or any other partitioning tool prior to use this function.</p>
<p>Note that there are two partitioning rules, FDISK and SFD. The FDISK partitioning is usually used for harddisk, MMC, SDC, CFC and U Disk. It can divide a physical drive into one or more partitions with a partition table on the MBR. However Windows does not support multiple partition on the removable media. The SFD is non-partitioned method. The FAT volume starts from the first sector on the physical drive without partition table. It is usually used for floppy disk, Microdrive, optical disk and super-floppy media.</p>
<p>The FAT sub-type, FAT12/FAT16/FAT32, is determined by number of clusters on the volume and nothing else, according to the FAT specification issued by Microsoft. Thus which FAT sub-type is selected, is depends on the volume size and the specified cluster size. The cluster size affects performance of the file system and large cluster increases the performance.</p>
<p>When the number of clusters gets near the FAT sub-type boundaries, the function can fail with <tt>FR_MKFS_ABORTED</tt>.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_READOLNY == 0</tt> and <tt>_USE_MKFS == 1</tt>.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="filename.html#vol">Volume management</a>, <a href="fdisk.html">f_fdisk</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/mkfs.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_mkfs</title>
</head>
<body>
<div class="para func">
<h2>f_mkfs</h2>
<p>The f_mkfs fucntion creates an FAT file system on the logical drive.</p>
<pre>
FRESULT f_mkfs (
const TCHAR* <span class="arg">path</span>, <span class="c">/* [IN] Logical drive number */</span>
BYTE <span class="arg">sfd</span>, <span class="c">/* [IN] Partitioning rule */</span>
UINT <span class="arg">au</span> <span class="c">/* [IN] Size of the allocation unit */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>path</dt>
<dd>Pinter to the null-terminated string that specifies the <a href="filename.html">logical drive</a> to be formatted. If there is no drive number, it means the default drive.</dd>
<dt>sfd</dt>
<dd>Specifies partitioning rule (FDISK(0) or SFD(1)). This argument will be ignored on some case.</dd>
<dt>au</dt>
<dd>Specifies size of the allocation unit (cluter) in unit of byte. The value must be sector size * n (n is 1 to 128 and power of 2). When a zero is given, the cluster size is determined depends on the volume size.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#wp">FR_WRITE_PROTECTED</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>,
<a href="rc.html#ne">FR_NOT_ENABLED</a>,
<a href="rc.html#ma">FR_MKFS_ABORTED</a>,
<a href="rc.html#ip">FR_INVALID_PARAMETER</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_mkfs()</tt> function creates an FAT volume on the logical drive. When FDISK format is specified, a primary partition occupies the entire disk space is created and then an FAT volume is created on the partition. When SFD format is specified, the FAT volume starts from the first sector of the physical drive.</p>
<p>If the logical drive has been bound to any partition (1-4) by multiple partition feature (<tt>_MULTI_PARTITION</tt>), the FAT volume is created into the specified partition. In this case, the second argument <tt class="arg">sfd</tt> is ignored. The physical drive must have been partitioned with <tt>f_fdisk()</tt> function or any other partitioning tool prior to use this function.</p>
<p>Note that there are two partitioning rules, FDISK and SFD. The FDISK partitioning is usually used for harddisk, MMC, SDC, CFC and U Disk. It can divide a physical drive into one or more partitions with a partition table on the MBR. However Windows does not support multiple partition on the removable media. The SFD is non-partitioned method. The FAT volume starts from the first sector on the physical drive without partition table. It is usually used for floppy disk, Microdrive, optical disk and super-floppy media.</p>
<p>The FAT sub-type, FAT12/FAT16/FAT32, is determined by number of clusters on the volume and nothing else, according to the FAT specification issued by Microsoft. Thus which FAT sub-type is selected, is depends on the volume size and the specified cluster size. The cluster size affects performance of the file system and large cluster increases the performance.</p>
<p>When the number of clusters gets near the FAT sub-type boundaries, the function can fail with <tt>FR_MKFS_ABORTED</tt>.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_READOLNY == 0</tt> and <tt>_USE_MKFS == 1</tt>.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="filename.html#vol">Volume management</a>, <a href="fdisk.html">f_fdisk</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,83 +1,83 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/mount.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_mount</title>
</head>
<body>
<div class="para func">
<h2>f_mount</h2>
<p>The f_mount fucntion registers/unregisters file system object to the FatFs module.</p>
<pre>
FRESULT f_mount (
FATFS* <span class="arg">fatfs</span>, <span class="c">/* [IN] File system object */</span>
const TCHAR* <span class="arg">path</span>, <span class="c">/* [IN] Logical drive number */</span>
BYTE <span class="arg">opt</span> <span class="c">/* [IN] Initialization option */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>fatfs</dt>
<dd>Pointer to the new file system object to be registered. Null pointer unregisters the registered file system object.</dd>
<dt>path</dt>
<dd>Pointer to the null-terminated string that specifies the <a href="filename.html">logical drive</a>. The string with no drive number means the default drive.</dd>
<dt>opt</dt>
<dd>Initialization option. 0: Do not mount now (to be mounted later), 1: Force mounted the volume to check if the FAT volume is available.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#ns">FR_NO_FILESYSTEM</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_mount()</tt> function registers/unregisters a file system object used for the logical drive to the FatFs module as follows:</p>
<ol>
<li>Determines the logical drive which specified by <tt class="arg">path</tt>.</li>
<li>Clears and unregisters the regsitered work area of the drive.</li>
<li>Clears and registers the new work area to the drive if <tt class="arg">fatfs</tt> is not NULL.</li>
<li>Performs volume mount process to the drive if forced mount is specified.</li>
</ol>
<p>The file system object is the work area needed for each logical drive. It must be given to the logical drive with this function prior to use any other file functions except for <tt>f_fdisk()</tt> function. To unregister a work area, specify a NULL to the <tt class="arg">fatfs</tt>, and then the work area can be discarded.</p>
<p>If forced mount is not specified, this function always succeeds regardless of the physical drive status due to delayed mount feature. It only clears (de-initializes) the given work area and registers its address to the internal table. No activity of the physical drive in this function. It can also be used to force de-initialized the registered work area of a logical drive. The volume mount processes, initialize the corresponding physical drive, find the FAT volume in it and initialize the work area, is performed in the subsequent file access functions when either or both of following condition is true.</p>
<ul>
<li>File system object is not initialized. It is cleared by <tt>f_mount()</tt>.</li>
<li>Physical drive is not initialized. It is de-initialized by system reset or media removal.</li>
</ul>
<p>If the function with forced mount failed, it means that the file system object is registered but the volume is currently not available. Mount process will also be attempted in subsequent file access functions.</p>
<p>If implementation of the disk I/O layer lacks media change detection, application program needs to perform a <tt>f_mount()</tt> after each media change to force cleared the file system object.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Always available.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a></tt>, <tt><a href="sfatfs.html">FATFS</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/mount.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_mount</title>
</head>
<body>
<div class="para func">
<h2>f_mount</h2>
<p>The f_mount fucntion registers/unregisters file system object to the FatFs module.</p>
<pre>
FRESULT f_mount (
FATFS* <span class="arg">fs</span>, <span class="c">/* [IN] File system object */</span>
const TCHAR* <span class="arg">path</span>, <span class="c">/* [IN] Logical drive number */</span>
BYTE <span class="arg">opt</span> <span class="c">/* [IN] Initialization option */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>fs</dt>
<dd>Pointer to the new file system object to be registered. Null pointer unregisters the registered file system object.</dd>
<dt>path</dt>
<dd>Pointer to the null-terminated string that specifies the <a href="filename.html">logical drive</a>. The string with no drive number means the default drive.</dd>
<dt>opt</dt>
<dd>Initialization option. 0: Do not mount now (to be mounted later), 1: Force mounted the volume to check if the FAT volume is available.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#ns">FR_NO_FILESYSTEM</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_mount()</tt> function registers/unregisters a file system object used for the logical drive to the FatFs module as follows:</p>
<ol>
<li>Determines the logical drive which specified by <tt class="arg">path</tt>.</li>
<li>Clears and unregisters the regsitered work area of the drive.</li>
<li>Clears and registers the new work area to the drive if <tt class="arg">fs</tt> is not NULL.</li>
<li>Performs volume mount process to the drive if forced mount is specified.</li>
</ol>
<p>The file system object is the work area needed for each logical drive. It must be given to the logical drive with this function prior to use any other file functions except for <tt>f_fdisk()</tt> function. To unregister a work area, specify a NULL to the <tt class="arg">fs</tt>, and then the work area can be discarded.</p>
<p>If forced mount is not specified, this function always succeeds regardless of the physical drive status due to delayed mount feature. It only clears (de-initializes) the given work area and registers its address to the internal table. No activity of the physical drive in this function. It can also be used to force de-initialized the registered work area of a logical drive. The volume mount processes, initialize the corresponding physical drive, find the FAT volume in it and initialize the work area, is performed in the subsequent file access functions when either or both of following condition is true.</p>
<ul>
<li>File system object is not initialized. It is cleared by <tt>f_mount()</tt>.</li>
<li>Physical drive is not initialized. It is de-initialized by system reset or media removal.</li>
</ul>
<p>If the function with forced mount failed, it means that the file system object is registered but the volume is currently not available. Mount process will also be attempted in subsequent file access functions.</p>
<p>If implementation of the disk I/O layer lacks media change detection, application program needs to perform a <tt>f_mount()</tt> after each media change to force cleared the file system object.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Always available.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a></tt>, <tt><a href="sfatfs.html">FATFS</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,173 +1,173 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/open.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_open</title>
</head>
<body>
<div class="para func">
<h2>f_open</h2>
<p>The f_open function creates a <em>file object</em> to be used to access the file.</p>
<pre>
FRESULT f_open (
FIL* <span class="arg">fp</span>, <span class="c">/* [OUT] Pointer to the file object structure */</span>
const TCHAR* <span class="arg">path</span>, <span class="c">/* [IN] File name */</span>
BYTE <span class="arg">mode</span> <span class="c">/* [IN] Mode flags */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>fp</dt>
<dd>Pointer to the blank file object structure to be created.</dd>
<dt>path</dt>
<dd>Pointer to a null-terminated string that specifies the <a href="filename.html">file name</a> to open or create.</dd>
<dt>mode</dt>
<dd>Mode flags that specifies the type of access and open method for the file. It is specified by a combination of following flags.<br>
<table class="lst">
<tr><th>Value</th><th>Description</th></tr>
<tr><td>FA_READ</td><td>Specifies read access to the object. Data can be read from the file. Combine with <tt>FA_WRITE</tt> for read-write access.</td></tr>
<tr><td>FA_WRITE</td><td>Specifies write access to the object. Data can be written to the file. Combine with <tt>FA_READ</tt> for read-write access.</td></tr>
<tr><td>FA_OPEN_EXISTING</td><td>Opens the file. The function fails if the file is not existing. (Default)</td></tr>
<tr><td>FA_OPEN_ALWAYS</td><td>Opens the file if it is existing. If not, a new file is created.<br>
To append data to the file, use <a href="lseek.html"><tt>f_lseek()</tt></a> function after file open in this method.</td></tr>
<tr><td>FA_CREATE_NEW</td><td>Creates a new file. The function fails with <tt>FR_EXIST</tt> if the file is existing.</td></tr>
<tr><td>FA_CREATE_ALWAYS</td><td>Creates a new file. If the file is existing, it will be truncated and overwritten.</td></tr>
</table>
</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#ok">FR_NO_FILE</a>,
<a href="rc.html#np">FR_NO_PATH</a>,
<a href="rc.html#in">FR_INVALID_NAME</a>,
<a href="rc.html#de">FR_DENIED</a>,
<a href="rc.html#ex">FR_EXIST</a>,
<a href="rc.html#io">FR_INVALID_OBJECT</a>,
<a href="rc.html#wp">FR_WRITE_PROTECTED</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>,
<a href="rc.html#ne">FR_NOT_ENABLED</a>,
<a href="rc.html#ns">FR_NO_FILESYSTEM</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>,
<a href="rc.html#lo">FR_LOCKED</a>,
<a href="rc.html#nc">FR_NOT_ENOUGH_CORE</a>,
<a href="rc.html#tf">FR_TOO_MANY_OPEN_FILES</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>After <tt>f_open()</tt> function succeeded, the file object is valid. The file object is used for subsequent read/write functions to identify the file. To close an open file, use <a href="close.html"><tt>f_close()</tt></a> function. If the file is modified and not closed properly, the file data will be collapsed.</p>
<p>If duplicated file open is needed, read <a href="appnote.html#dup">here</a> carefully. However duplicated open of a file with write mode flag is always prohibited.</p>
<p>Before using any file function, a work area (file system object) must be registered to the logical drive with <a href="mount.html"><tt>f_mount()</tt></a> function. All API functions except for <a href="fdisk.html"><tt>f_fdisk()</tt></a> function can work after this procedure.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Always available. The mode flags, <tt>FA_WRITE, FA_CREATE_ALWAYS, FA_CREATE_NEW and FA_OPEN_ALWAYS</tt>, are not available when <tt>_FS_READONLY == 1</tt>.</p>
</div>
<div class="para use">
<h4>Example</h4>
<pre>
<span class="c">/* Read a text file and display it */</span>
FATFS FatFs; <span class="c">/* Work area (file system object) for logical drive */</span>
int main (void)
{
FIL fil; <span class="c">/* File object */</span>
char line[82]; <span class="c">/* Line buffer */</span>
FRESULT fr; <span class="c">/* FatFs return code */</span>
<span class="c">/* Register work area to the default drive */</span>
f_mount(&amp;FatFs, "", 0);
<span class="c">/* Open a text file */</span>
fr = f_open(&amp;fil, "message.txt", FA_READ);
if (fr) return (int)fr;
<span class="c">/* Read all lines and display it */</span>
while (f_gets(line, sizeof line, &amp;fil))
printf(line);
<span class="c">/* Close the file */</span>
f_close(&amp;fil);
return 0;
}
</pre>
<pre>
<span class="c">/* Copy a file "file.bin" on the drive 1 to drive 0 */</span>
int main (void)
{
FATFS fs[2]; <span class="c">/* Work area (file system object) for logical drives */</span>
FIL fsrc, fdst; <span class="c">/* File objects */</span>
BYTE buffer[4096]; <span class="c">/* File copy buffer */</span>
FRESULT fr; <span class="c">/* FatFs function common result code */</span>
UINT br, bw; <span class="c">/* File read/write count */</span>
<span class="c">/* Register work area for each logical drive */</span>
f_mount(&amp;fs[0], "0:", 0);
f_mount(&amp;fs[1], "1:", 0);
<span class="c">/* Open source file on the drive 1 */</span>
fr = f_open(&amp;fsrc, "1:file.bin", FA_OPEN_EXISTING | FA_READ);
if (fr) return (int)fr;
<span class="c">/* Create destination file on the drive 0 */</span>
fr = f_open(&amp;fdst, "0:file.bin", FA_CREATE_ALWAYS | FA_WRITE);
if (fr) return (int)fr;
<span class="c">/* Copy source to destination */</span>
for (;;) {
fr = f_read(&amp;fsrc, buffer, sizeof buffer, &amp;br); <span class="c">/* Read a chunk of source file */</span>
if (fr || br == 0) break; <span class="c">/* error or eof */</span>
fr = f_write(&amp;fdst, buffer, br, &amp;bw); <span class="c">/* Write it to the destination file */</span>
if (fr || bw &lt; br) break; <span class="c">/* error or disk full */</span>
}
<span class="c">/* Close open files */</span>
f_close(&amp;fsrc);
f_close(&amp;fdst);
<span class="c">/* Unregister work area prior to discard it */</span>
f_mount(NULL, "0:", 0);
f_mount(NULL, "1:", 0);
return (int)fr;
}
</pre>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="read.html">f_read</a>, <a href="write.html">f_write</a>, <a href="close.html">f_close</a>, <a href="sfile.html">FIL</a>, <a href="sfatfs.html">FATFS</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/open.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_open</title>
</head>
<body>
<div class="para func">
<h2>f_open</h2>
<p>The f_open function creates a <em>file object</em> to be used to access the file.</p>
<pre>
FRESULT f_open (
FIL* <span class="arg">fp</span>, <span class="c">/* [OUT] Pointer to the file object structure */</span>
const TCHAR* <span class="arg">path</span>, <span class="c">/* [IN] File name */</span>
BYTE <span class="arg">mode</span> <span class="c">/* [IN] Mode flags */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>fp</dt>
<dd>Pointer to the blank file object structure to be created.</dd>
<dt>path</dt>
<dd>Pointer to a null-terminated string that specifies the <a href="filename.html">file name</a> to open or create.</dd>
<dt>mode</dt>
<dd>Mode flags that specifies the type of access and open method for the file. It is specified by a combination of following flags.<br>
<table class="lst">
<tr><th>Value</th><th>Description</th></tr>
<tr><td>FA_READ</td><td>Specifies read access to the object. Data can be read from the file. Combine with <tt>FA_WRITE</tt> for read-write access.</td></tr>
<tr><td>FA_WRITE</td><td>Specifies write access to the object. Data can be written to the file. Combine with <tt>FA_READ</tt> for read-write access.</td></tr>
<tr><td>FA_OPEN_EXISTING</td><td>Opens the file. The function fails if the file is not existing. (Default)</td></tr>
<tr><td>FA_OPEN_ALWAYS</td><td>Opens the file if it is existing. If not, a new file is created.<br>
To append data to the file, use <a href="lseek.html"><tt>f_lseek()</tt></a> function after file open in this method.</td></tr>
<tr><td>FA_CREATE_NEW</td><td>Creates a new file. The function fails with <tt>FR_EXIST</tt> if the file is existing.</td></tr>
<tr><td>FA_CREATE_ALWAYS</td><td>Creates a new file. If the file is existing, it will be truncated and overwritten.</td></tr>
</table>
</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#ok">FR_NO_FILE</a>,
<a href="rc.html#np">FR_NO_PATH</a>,
<a href="rc.html#in">FR_INVALID_NAME</a>,
<a href="rc.html#de">FR_DENIED</a>,
<a href="rc.html#ex">FR_EXIST</a>,
<a href="rc.html#io">FR_INVALID_OBJECT</a>,
<a href="rc.html#wp">FR_WRITE_PROTECTED</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>,
<a href="rc.html#ne">FR_NOT_ENABLED</a>,
<a href="rc.html#ns">FR_NO_FILESYSTEM</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>,
<a href="rc.html#lo">FR_LOCKED</a>,
<a href="rc.html#nc">FR_NOT_ENOUGH_CORE</a>,
<a href="rc.html#tf">FR_TOO_MANY_OPEN_FILES</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>After <tt>f_open()</tt> function succeeded, the file object is valid. The file object is used for subsequent read/write functions to identify the file. To close an open file, use <a href="close.html"><tt>f_close()</tt></a> function. If the file is modified and not closed properly, the file data will be collapsed.</p>
<p>If duplicated file open is needed, read <a href="appnote.html#dup">here</a> carefully. However duplicated open of a file with write mode flag is always prohibited.</p>
<p>Before using any file function, a work area (file system object) must be registered to the logical drive with <a href="mount.html"><tt>f_mount()</tt></a> function. All API functions except for <a href="fdisk.html"><tt>f_fdisk()</tt></a> function can work after this procedure.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Always available. The mode flags, <tt>FA_WRITE, FA_CREATE_ALWAYS, FA_CREATE_NEW and FA_OPEN_ALWAYS</tt>, are not available when <tt>_FS_READONLY == 1</tt>.</p>
</div>
<div class="para use">
<h4>Example</h4>
<pre>
<span class="c">/* Read a text file and display it */</span>
FATFS FatFs; <span class="c">/* Work area (file system object) for logical drive */</span>
int main (void)
{
FIL fil; <span class="c">/* File object */</span>
char line[82]; <span class="c">/* Line buffer */</span>
FRESULT fr; <span class="c">/* FatFs return code */</span>
<span class="c">/* Register work area to the default drive */</span>
f_mount(&amp;FatFs, "", 0);
<span class="c">/* Open a text file */</span>
fr = f_open(&amp;fil, "message.txt", FA_READ);
if (fr) return (int)fr;
<span class="c">/* Read all lines and display it */</span>
while (f_gets(line, sizeof line, &amp;fil))
printf(line);
<span class="c">/* Close the file */</span>
f_close(&amp;fil);
return 0;
}
</pre>
<pre>
<span class="c">/* Copy a file "file.bin" on the drive 1 to drive 0 */</span>
int main (void)
{
FATFS fs[2]; <span class="c">/* Work area (file system object) for logical drives */</span>
FIL fsrc, fdst; <span class="c">/* File objects */</span>
BYTE buffer[4096]; <span class="c">/* File copy buffer */</span>
FRESULT fr; <span class="c">/* FatFs function common result code */</span>
UINT br, bw; <span class="c">/* File read/write count */</span>
<span class="c">/* Register work area for each logical drive */</span>
f_mount(&amp;fs[0], "0:", 0);
f_mount(&amp;fs[1], "1:", 0);
<span class="c">/* Open source file on the drive 1 */</span>
fr = f_open(&amp;fsrc, "1:file.bin", FA_OPEN_EXISTING | FA_READ);
if (fr) return (int)fr;
<span class="c">/* Create destination file on the drive 0 */</span>
fr = f_open(&amp;fdst, "0:file.bin", FA_CREATE_ALWAYS | FA_WRITE);
if (fr) return (int)fr;
<span class="c">/* Copy source to destination */</span>
for (;;) {
fr = f_read(&amp;fsrc, buffer, sizeof buffer, &amp;br); <span class="c">/* Read a chunk of source file */</span>
if (fr || br == 0) break; <span class="c">/* error or eof */</span>
fr = f_write(&amp;fdst, buffer, br, &amp;bw); <span class="c">/* Write it to the destination file */</span>
if (fr || bw &lt; br) break; <span class="c">/* error or disk full */</span>
}
<span class="c">/* Close open files */</span>
f_close(&amp;fsrc);
f_close(&amp;fdst);
<span class="c">/* Unregister work area prior to discard it */</span>
f_mount(NULL, "0:", 0);
f_mount(NULL, "1:", 0);
return (int)fr;
}
</pre>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="read.html">f_read</a>, <a href="write.html">f_write</a>, <a href="close.html">f_close</a>, <a href="sfile.html">FIL</a>, <a href="sfatfs.html">FATFS</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,75 +1,75 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/opendir.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_opendir</title>
</head>
<body>
<div class="para func">
<h2>f_opendir</h2>
<p>The f_opendir function opens a directory.</p>
<pre>
FRESULT f_opendir (
DIR* <span class="arg">dp</span>, <span class="c">/* [OUT] Pointer to the directory object structure */</span>
const TCHAR* <span class="arg">path</span> <span class="c">/* [IN] Directory name */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>dp</dt>
<dd>Pointer to the blank directory object to create a new one.</dd>
<dt>path</dt>
<dd>Pinter to the null-terminated string that specifies the <a href="filename.html">directory name</a> to be opened.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#np">FR_NO_PATH</a>,
<a href="rc.html#in">FR_INVALID_NAME</a>,
<a href="rc.html#io">FR_INVALID_OBJECT</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>,
<a href="rc.html#ne">FR_NOT_ENABLED</a>,
<a href="rc.html#ns">FR_NO_FILESYSTEM</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>,
<a href="rc.html#nc">FR_NOT_ENOUGH_CORE</a>,
<a href="rc.html#tf">FR_TOO_MANY_OPEN_FILES</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_opendir()</tt> function opens an exsisting directory and creates a directory object for subsequent <tt>f_readdir()</tt> function.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_MINIMIZE &lt;= 1</tt>.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="readdir.html">f_readdir</a>, <a href="closedir.html">f_closedir</a>, <a href="sdir.html">DIR</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/opendir.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_opendir</title>
</head>
<body>
<div class="para func">
<h2>f_opendir</h2>
<p>The f_opendir function opens a directory.</p>
<pre>
FRESULT f_opendir (
DIR* <span class="arg">dp</span>, <span class="c">/* [OUT] Pointer to the directory object structure */</span>
const TCHAR* <span class="arg">path</span> <span class="c">/* [IN] Directory name */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>dp</dt>
<dd>Pointer to the blank directory object to create a new one.</dd>
<dt>path</dt>
<dd>Pinter to the null-terminated string that specifies the <a href="filename.html">directory name</a> to be opened.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#np">FR_NO_PATH</a>,
<a href="rc.html#in">FR_INVALID_NAME</a>,
<a href="rc.html#io">FR_INVALID_OBJECT</a>,
<a href="rc.html#id">FR_INVALID_DRIVE</a>,
<a href="rc.html#ne">FR_NOT_ENABLED</a>,
<a href="rc.html#ns">FR_NO_FILESYSTEM</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>,
<a href="rc.html#nc">FR_NOT_ENOUGH_CORE</a>,
<a href="rc.html#tf">FR_TOO_MANY_OPEN_FILES</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_opendir()</tt> function opens an exsisting directory and creates a directory object for subsequent <tt>f_readdir()</tt> function.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_MINIMIZE &lt;= 1</tt>.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="readdir.html">f_readdir</a>, <a href="closedir.html">f_closedir</a>, <a href="sdir.html">DIR</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,62 +1,62 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/putc.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_putc</title>
</head>
<body>
<div class="para func">
<h2>f_putc</h2>
<p>The f_putc funciton puts a character to the file.</p>
<pre>
int f_putc (
TCHAR <span class="arg">chr</span>, <span class="c">/* [IN] A character to put */</span>
FIL* <span class="arg">fp</span> <span class="c">/* [IN] File object */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>chr</dt>
<dd>A character to be put.</dd>
<dt>fp</dt>
<dd>Pointer to the open file object structuer.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>When the character was written successfuly, it returns number of characters written. When the function failed due to disk full or any error, an <tt>EOF (-1)</tt> will be returned.</p>
<p>When FatFs is configured to Unicode API (<tt>_LFN_UNICODE == 1</tt>), character encoding on the string fuctions, <tt>f_putc()</tt>, <tt>f_puts()</tt>, <tt>f_printf()</tt> and <tt>f_gets()</tt>, is also switched to Unicode. The character encoding on the file to be read/written via those functions is selected by <tt>_STRF_ENCODE</tt> option.</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_putc()</tt> function is a wrapper function of <a href="write.html"><tt>f_write()</tt></a> function.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_READONLY == 0</tt> and <tt>_USE_STRFUNC</tt> is 1 or 2. When it is set to 2, a <tt>'\n'</tt> is converted to <tt>'\r'+'\n'</tt>.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a>, <a href="puts.html">f_puts</a>, <a href="printf.html">f_printf</a>, <a href="gets.html">f_gets</a>, <a href="close.html">f_close</a>, <a href="sfile.html">FIL</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/putc.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_putc</title>
</head>
<body>
<div class="para func">
<h2>f_putc</h2>
<p>The f_putc funciton puts a character to the file.</p>
<pre>
int f_putc (
TCHAR <span class="arg">chr</span>, <span class="c">/* [IN] A character to put */</span>
FIL* <span class="arg">fp</span> <span class="c">/* [IN] File object */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>chr</dt>
<dd>A character to be put.</dd>
<dt>fp</dt>
<dd>Pointer to the open file object structuer.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>When the character was written successfuly, it returns number of characters written. When the function failed due to disk full or any error, an <tt>EOF (-1)</tt> will be returned.</p>
<p>When FatFs is configured to Unicode API (<tt>_LFN_UNICODE == 1</tt>), character encoding on the string fuctions, <tt>f_putc()</tt>, <tt>f_puts()</tt>, <tt>f_printf()</tt> and <tt>f_gets()</tt>, is also switched to Unicode. The character encoding on the file to be read/written via those functions is selected by <tt>_STRF_ENCODE</tt> option.</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_putc()</tt> function is a wrapper function of <a href="write.html"><tt>f_write()</tt></a> function.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_READONLY == 0</tt> and <tt>_USE_STRFUNC</tt> is 1 or 2. When it is set to 2, a <tt>'\n'</tt> is converted to <tt>'\r'+'\n'</tt>.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a>, <a href="puts.html">f_puts</a>, <a href="printf.html">f_printf</a>, <a href="gets.html">f_gets</a>, <a href="close.html">f_close</a>, <a href="sfile.html">FIL</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

View file

@ -1,62 +1,62 @@
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/puts.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_puts</title>
</head>
<body>
<div class="para func">
<h2>f_puts</h2>
<p>The f_puts function writes a string to the file.</p>
<pre>
int f_puts (
const TCHAR* <span class="arg">str</span>, <span class="c">/* [IN] String */</span>
FIL* <span class="arg">fp</span> <span class="c">/* [IN] File object */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>str</dt>
<dd>Pointer to the null terminated string to be written. The terminator character will not be written.</dd>
<dt>fp</dt>
<dd>Pointer to the open file object structure.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Value</h4>
<p>When the function succeeded, it returns number of characters written. When the write operation is aborted due to disk full or any error, an <tt>EOF (-1)</tt> will be returned.</p>
<p>When FatFs is configured to Unicode API (<tt>_LFN_UNICODE == 1</tt>), character encoding on the srting fuctions, <tt>f_putc()</tt>, <tt>f_puts()</tt>, <tt>f_printf()</tt> and <tt>f_gets()</tt>, is also switched to Unicode. The character encoding on the file to be read/written via those functions is selected by <tt>_STRF_ENCODE</tt> option.</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_puts()</tt> function is a wrapper function of <a href="write.html"><tt>f_write()</tt></a> function.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_READONLY == 0</tt> and <tt>_USE_STRFUNC</tt> is 1 or 2. When it is set to 2, <tt>'\n'</tt>s contained in the string are converted to <tt>'\r'+'\n'</tt>.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a>, <a href="putc.html">f_putc</a>, <a href="printf.html">f_printf</a>, <a href="gets.html">f_gets</a>, <a href="close.html">f_close</a>, <a href="sfile.html">FIL</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/puts.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_puts</title>
</head>
<body>
<div class="para func">
<h2>f_puts</h2>
<p>The f_puts function writes a string to the file.</p>
<pre>
int f_puts (
const TCHAR* <span class="arg">str</span>, <span class="c">/* [IN] String */</span>
FIL* <span class="arg">fp</span> <span class="c">/* [IN] File object */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>str</dt>
<dd>Pointer to the null terminated string to be written. The terminator character will not be written.</dd>
<dt>fp</dt>
<dd>Pointer to the open file object structure.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Value</h4>
<p>When the function succeeded, it returns number of characters written. When the write operation is aborted due to disk full or any error, an <tt>EOF (-1)</tt> will be returned.</p>
<p>When FatFs is configured to Unicode API (<tt>_LFN_UNICODE == 1</tt>), character encoding on the srting fuctions, <tt>f_putc()</tt>, <tt>f_puts()</tt>, <tt>f_printf()</tt> and <tt>f_gets()</tt>, is also switched to Unicode. The character encoding on the file to be read/written via those functions is selected by <tt>_STRF_ENCODE</tt> option.</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The <tt>f_puts()</tt> function is a wrapper function of <a href="write.html"><tt>f_write()</tt></a> function.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Available when <tt>_FS_READONLY == 0</tt> and <tt>_USE_STRFUNC</tt> is 1 or 2. When it is set to 2, <tt>'\n'</tt>s contained in the string are converted to <tt>'\r'+'\n'</tt>.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a>, <a href="putc.html">f_putc</a>, <a href="printf.html">f_printf</a>, <a href="gets.html">f_gets</a>, <a href="close.html">f_close</a>, <a href="sfile.html">FIL</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>

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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/rc.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - Return Codes</title>
</head>
<body>
<h1>Return Code of the File Functions</h1>
<p>On the FatFs API, most of file functions return common result code as enum type <tt>FRESULT</tt>. When a function succeeded, it returns zero, otherwise returns non-zero value that indicates type of error.</p>
<dl class="ret">
<dt id="ok">FR_OK (0)</dt>
<dd>The function succeeded.</dd>
<dt id="de">FR_DISK_ERR</dt>
<dd>An unrecoverable hard error occured in the lower layer, <tt>disk_read()</tt>, <tt>disk_write()</tt> or <tt>disk_ioctl()</tt> function.<br>Note that if once this error occured at any operation to an open file, the file object is aborted and all operations to the file except for close will be rejected.</dd>
<dt id="ie">FR_INT_ERR</dt>
<dd>Assertion failed. An insanity is detected in the internal process. One of the following possibilities are suspected.
<ul>
<li>There is any error of the FAT structure on the volume.</li>
<li>Work area (file system object, file object or etc...) is broken by stack overflow or any other application. This is the reason in most case.</li>
</ul>
Note that if once this error occured at any operation to an open file, the file object is aborted and all operations to the file except for close will be rejected.
</dd>
<dt id="nr">FR_NOT_READY</dt>
<dd>The disk drive cannot work due to incorrect medium removal or <tt>disk_initialize()</tt> function failed.</dd>
<dt id="nf">FR_NO_FILE</dt>
<dd>Could not find the file.</dd>
<dt id="np">FR_NO_PATH</dt>
<dd>Could not find the path.</dd>
<dt id="in">FR_INVALID_NAME</dt>
<dd>The given string is invalid as the <a href="filename.html">path name</a>.</dd>
<dt id="dn">FR_DENIED</dt>
<dd>The required access was denied due to one of the following reasons:
<ul>
<li>Write mode open against the read-only file.</li>
<li>Deleting the read-only file or directory.</li>
<li>Deleting the non-empty directory or current directory.</li>
<li>Reading the file opened without <tt>FA_READ</tt> flag.</li>
<li>Any modification to the file opened without <tt>FA_WRITE</tt> flag.</li>
<li>Could not create the file or directory due to the directory table is full.</li>
<li>Could not create the directory due to the volume is full.</li>
</ul>
</dd>
<dt id="ex">FR_EXIST</dt>
<dd>Name collision. Any object that has the same name is already existing.</dd>
<dt id="io">FR_INVALID_OBJECT</dt>
<dd>The file/directory object structure is invalid or a null pointer is given. All open objects of the logical drive are invalidated by the voulme mount process.</dd>
<dt id="wp">FR_WRITE_PROTECTED</dt>
<dd>Any write mode action against the write-protected media.</dd>
<dt id="id">FR_INVALID_DRIVE</dt>
<dd>Invalid drive number is specified in the path name. A null pointer is given as the path name. (Related option: <tt>_VOLUMES</tt>)</dd>
<dt id="ne">FR_NOT_ENABLED</dt>
<dd>Work area for the logical drive has not been registered by <tt>f_mount()</tt> function.</dd>
<dt id="ns">FR_NO_FILESYSTEM</dt>
<dd>There is no valid FAT volume on the drive.</dd>
<dt id="ma">FR_MKFS_ABORTED</dt>
<dd>The <tt>f_mkfs()</tt> function aborted before start in format due to a reason as follows:
<ul>
<li>The disk/partition size is too small.</li>
<li>Not allowable cluster size for this disk. This can occure when number of clusters gets near the boundaries of FAT sub-types.</li>
<li>There is no partition related to the logical drive. (Related option: <tt>_MULTI_PARTITION</tt>)</li>
</ul>
</dd>
<dt id="tm">FR_TIMEOUT</dt>
<dd>The function was canceled due to a timeout of <a href="appnote.html#reentrant">thread-safe control</a>. (Related option: <tt>_TIMEOUT</tt>)</dd>
<dt id="lo">FR_LOCKED</dt>
<dd>The operation to the object was rejected by <a href="appnote.html#dup">file sharing control</a>. (Related option: <tt>_FS_LOCK</tt>)</dd>
<dt id="nc">FR_NOT_ENOUGH_CORE</dt>
<dd>Not enough memory for the operation. There is one of the following reasons:
<ul>
<li>Could not allocate a memory for LFN working buffer. (Related option: <tt>_USE_LFN</tt>)</li>
<li>Size of the given CLMT buffer is insufficient for the file fragments.</li>
</ul>
</dd>
<dt id="tf">FR_TOO_MANY_OPEN_FILES</dt>
<dd>Number of open objects has been reached maximum value and no more object can be opened. (Related option: <tt>_FS_LOCK</tt>)</dd>
<dt id="ip">FR_INVALID_PARAMETER</dt>
<dd>The given parameter is invalid or there is any inconsistent.</dd>
</dl>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/rc.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - Return Codes</title>
</head>
<body>
<h1>Return Code of the File Functions</h1>
<p>On the FatFs API, most of file functions return common result code as enum type <tt>FRESULT</tt>. When a function succeeded, it returns zero, otherwise returns non-zero value that indicates type of error.</p>
<dl class="ret">
<dt id="ok">FR_OK (0)</dt>
<dd>The function succeeded.</dd>
<dt id="de">FR_DISK_ERR</dt>
<dd>An unrecoverable hard error occured in the lower layer, <tt>disk_read()</tt>, <tt>disk_write()</tt> or <tt>disk_ioctl()</tt> function.<br>Note that if once this error occured at any operation to an open file, the file object is aborted and all operations to the file except for close will be rejected.</dd>
<dt id="ie">FR_INT_ERR</dt>
<dd>Assertion failed. An insanity is detected in the internal process. One of the following possibilities is suspected.
<ul>
<li>Work area (file system object, file object or etc...) is broken by stack overflow or any other application. This is the reason in most case.</li>
<li>There is any error of the FAT structure on the volume.</li>
</ul>
Note that if once this error occured at any operation to an open file, the file object is aborted and all operations to the file except for close will be rejected.
</dd>
<dt id="nr">FR_NOT_READY</dt>
<dd>The disk drive cannot work due to incorrect medium removal or <tt>disk_initialize()</tt> function failed.</dd>
<dt id="nf">FR_NO_FILE</dt>
<dd>Could not find the file.</dd>
<dt id="np">FR_NO_PATH</dt>
<dd>Could not find the path.</dd>
<dt id="in">FR_INVALID_NAME</dt>
<dd>The given string is invalid as the <a href="filename.html">path name</a>.</dd>
<dt id="dn">FR_DENIED</dt>
<dd>The required access was denied due to one of the following reasons:
<ul>
<li>Write mode open against the read-only file.</li>
<li>Deleting the read-only file or directory.</li>
<li>Deleting the non-empty directory or current directory.</li>
<li>Reading the file opened without <tt>FA_READ</tt> flag.</li>
<li>Any modification to the file opened without <tt>FA_WRITE</tt> flag.</li>
<li>Could not create the file or directory due to the directory table is full.</li>
<li>Could not create the directory due to the volume is full.</li>
</ul>
</dd>
<dt id="ex">FR_EXIST</dt>
<dd>Name collision. Any object that has the same name is already existing.</dd>
<dt id="io">FR_INVALID_OBJECT</dt>
<dd>The file/directory object structure is invalid or a null pointer is given. All open objects of the logical drive are invalidated by the voulme mount process.</dd>
<dt id="wp">FR_WRITE_PROTECTED</dt>
<dd>Any write mode action against the write-protected media.</dd>
<dt id="id">FR_INVALID_DRIVE</dt>
<dd>Invalid drive number is specified in the path name. A null pointer is given as the path name. (Related option: <tt>_VOLUMES</tt>)</dd>
<dt id="ne">FR_NOT_ENABLED</dt>
<dd>Work area for the logical drive has not been registered by <tt>f_mount()</tt> function.</dd>
<dt id="ns">FR_NO_FILESYSTEM</dt>
<dd>There is no valid FAT volume on the drive.</dd>
<dt id="ma">FR_MKFS_ABORTED</dt>
<dd>The <tt>f_mkfs()</tt> function aborted before start in format due to a reason as follows:
<ul>
<li>The disk/partition size is too small.</li>
<li>Not allowable cluster size for this disk. This can occure when number of clusters gets near the boundaries of FAT sub-types.</li>
<li>There is no partition related to the logical drive. (Related option: <tt>_MULTI_PARTITION</tt>)</li>
</ul>
</dd>
<dt id="tm">FR_TIMEOUT</dt>
<dd>The function was canceled due to a timeout of <a href="appnote.html#reentrant">thread-safe control</a>. (Related option: <tt>_TIMEOUT</tt>)</dd>
<dt id="lo">FR_LOCKED</dt>
<dd>The operation to the object was rejected by <a href="appnote.html#dup">file sharing control</a>. (Related option: <tt>_FS_LOCK</tt>)</dd>
<dt id="nc">FR_NOT_ENOUGH_CORE</dt>
<dd>Not enough memory for the operation. There is one of the following reasons:
<ul>
<li>Could not allocate a memory for LFN working buffer. (Related option: <tt>_USE_LFN</tt>)</li>
<li>Size of the given CLMT buffer is insufficient for the file fragments.</li>
</ul>
</dd>
<dt id="tf">FR_TOO_MANY_OPEN_FILES</dt>
<dd>Number of open objects has been reached maximum value and no more object can be opened. (Related option: <tt>_FS_LOCK</tt>)</dd>
<dt id="ip">FR_INVALID_PARAMETER</dt>
<dd>The given parameter is invalid or there is any inconsistent.</dd>
</dl>
</body>
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<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/read.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_read</title>
</head>
<body>
<div class="para func">
<h2>f_read</h2>
<p>The f_read function reads data from a file.</p>
<pre>
FRESULT f_read (
FIL* <span class="arg">fp</span>, <span class="c">/* [IN] File object */</span>
void* <span class="arg">buff</span>, <span class="c">/* [OUT] Buffer to store read data */</span>
UINT <span class="arg">btr</span>, <span class="c">/* [IN] Number of bytes to read */</span>
UINT* <span class="arg">br</span> <span class="c">/* [OUT] Number of bytes read */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>fp</dt>
<dd>Pointer to the open file object.</dd>
<dt>buff</dt>
<dd>Pointer to the buffer to store read data.</dd>
<dt>btr</dt>
<dd>Number of bytes to read in range of <tt>UINT</tt> type.</dd>
<dt>br</dt>
<dd>Pointer to the <tt>UINT</tt> variable to return number of bytes read. The value is always valid after the function call regardless of the result.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#io">FR_INVALID_OBJECT</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The file read/write pointer of the file object advances number of bytes read. After the function succeeded, <tt class="arg">*br</tt> should be checked to detect the end of file. In case of <tt class="arg">*br</tt> is less than <tt class="arg">btr</tt>, it means the read/write pointer reached end of the file during read operation.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Always available.</p>
</div>
<div class="para ref">
<h4>See Also</h4>
<p><tt><a href="open.html">f_open</a>, <a href="gets.html">fgets</a>, <a href="write.html">f_write</a>, <a href="close.html">f_close</a>, <a href="sfile.html">FIL</a></tt></p>
</div>
<p class="foot"><a href="../00index_e.html">Return</a></p>
</body>
</html>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta http-equiv="Content-Style-Type" content="text/css">
<link rel="up" title="FatFs" href="../00index_e.html">
<link rel="alternate" hreflang="ja" title="Japanese" href="../ja/read.html">
<link rel="stylesheet" href="../css_e.css" type="text/css" media="screen" title="ELM Default">
<title>FatFs - f_read</title>
</head>
<body>
<div class="para func">
<h2>f_read</h2>
<p>The f_read function reads data from a file.</p>
<pre>
FRESULT f_read (
FIL* <span class="arg">fp</span>, <span class="c">/* [IN] File object */</span>
void* <span class="arg">buff</span>, <span class="c">/* [OUT] Buffer to store read data */</span>
UINT <span class="arg">btr</span>, <span class="c">/* [IN] Number of bytes to read */</span>
UINT* <span class="arg">br</span> <span class="c">/* [OUT] Number of bytes read */</span>
);
</pre>
</div>
<div class="para arg">
<h4>Parameters</h4>
<dl class="par">
<dt>fp</dt>
<dd>Pointer to the open file object.</dd>
<dt>buff</dt>
<dd>Pointer to the buffer to store read data.</dd>
<dt>btr</dt>
<dd>Number of bytes to read in range of <tt>UINT</tt> type.</dd>
<dt>br</dt>
<dd>Pointer to the <tt>UINT</tt> variable to return number of bytes read. The value is always valid after the function call regardless of the result.</dd>
</dl>
</div>
<div class="para ret">
<h4>Return Values</h4>
<p>
<a href="rc.html#ok">FR_OK</a>,
<a href="rc.html#de">FR_DISK_ERR</a>,
<a href="rc.html#ie">FR_INT_ERR</a>,
<a href="rc.html#nr">FR_NOT_READY</a>,
<a href="rc.html#io">FR_INVALID_OBJECT</a>,
<a href="rc.html#tm">FR_TIMEOUT</a>
</p>
</div>
<div class="para desc">
<h4>Description</h4>
<p>The file read/write pointer of the file object advances number of bytes read. After the function succeeded, <tt class="arg">*br</tt> should be checked to detect end of the file. In case of <tt class="arg">*br</tt> is less than <tt class="arg">btr</tt>, it means the read/write pointer reached end of the file during read operation.</p>
</div>
<div class="para comp">
<h4>QuickInfo</h4>
<p>Always available.</p>