TDISP: added custom character routine

demos/modules/tdisp/main.c

@@ -28,9 +28,11 @@ int main(void) {
 
 	tdispInit();
 
+	/* reset cursor position and clear the screen */
 	tdispHome();
 	tdispClear();
 
+	/* set cursor position and draw single characters */
 	tdispGotoXY(4, 0);
 	tdispDrawChar('H');
 	tdispDrawChar('D');
@@ -40,8 +42,22 @@ int main(void) {
 	tdispDrawChar('8');
 	tdispDrawChar('0');
 
+	/* draw a string to a given location */
 	tdispDrawStringLocation(0, 1, "chibios-gfx.com");
 
+	/* create and display a custom made character */
+	charmap[0] = 0b00000;
+	charmap[1] = 0b00100;
+	charmap[2] = 0b00010;
+	charmap[3] = 0b11111;
+	charmap[4] = 0b00010;
+	charmap[5] = 0b00100;
+	charmap[6] = 0b00000;
+	charmap[7] = 0b00000;
+	tdispCreateChar(0, charmap);
+	tdispHome();
+	tdispDrawChar(0);
+
 	while(TRUE) {
 		chThdSleepMilliseconds(250);	
 	}

drivers/tdisp/HD44780/tdisp_lld_config.h

@@ -38,6 +38,8 @@
 #define TDISP_DRIVER_NAME				"HD44780"
 #define TDISP_LLD(x)					tdisp_lld_##x##_HD44780
 
+#define TDISP_MAX_CUSTOM_CHARS			0x07
+
 #endif	/* GFX_USE_TDISP */
 
 #endif	/* _TDISP_LLD_CONFIG_H */

include/tdisp/tdisp.h

@@ -68,7 +68,7 @@ bool_t tdispInit(void);
 /**
  * @brief	Control different display properties
  * @note	Multiple attributes can be passed using the OR operator.
- * @note	Example: TDISP_DISPLAY_ON | TDISP_CURSOR_BLINK
+ * @note	Example: tdispSetAttributes(TDISP_DISPLAY_ON | TDISP_CURSOR_BLINK)
  *
  * @param[in] attributes	The attributes
  */
@@ -92,6 +92,17 @@ void tdispHome(void);
  */
 void tdispGotoXY(coord_t col, coord_t row);
 
+/**
+ * @brief	Store a custom character in the displays RAM
+ *
+ * @note	This usually must be done after each power-up since most
+ *			LCDs lose their RAM content.
+ *
+ * @param[in] location		On which address to store the character (from 0 up to max)
+ * @param[in] char			The character to be stored. This is an array.
+ */
+void tdispCreateChar(uint8_t location, char *charmap);
+
 /**
  * @brief	Draws a single character at the current cursor position
  *

src/tdisp/tdisp.c

@@ -78,6 +78,19 @@ void tdispHome(void) {
 	TDISP_LLD(write_cmd)(0x02);
 }
 
+void tdispCreateChar(uint8_t location, char *charmap) {
+	uint8_t i;
+
+	/* make sure we don't write somewhere we're not supposed to */
+	location &= TDISP_MAX_CUSTOM_CHARS;
+
+	TDISP_LLD(write_cmd)(0x40 | (location << 3));
+
+	for(i = 0; i < 8; i++) {
+		TDISP_LLD(write_data)(charmap[i]);
+	}
+}
+
 void tdispGotoXY(coord_t col, coord_t row) {
 	uint8_t row_offsets[] = { 0x00, 0x40, 0x14, 0x54 };