ugfx/demos/modules/gadc/gwinosc.c
2013-06-15 21:37:22 +10:00

190 lines
6.1 KiB
C

/*
* Copyright (c) 2012, 2013, Joel Bodenmann aka Tectu <joel@unormal.org>
* Copyright (c) 2012, 2013, Andrew Hannam aka inmarket
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of the <organization> nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/**
* --------------------------- Our Custom GWIN Oscilloscope ---------------
*
* This GWIN superset implements a simple audio oscilloscope using the GADC high speed device.
*/
#include "gfx.h"
#include "gwinosc.h"
/* Include internal GWIN routines so we can build our own superset class */
#include "gwin/internal.h"
/* Our GWIN identifier */
#define GW_SCOPE (GW_FIRST_USER_WINDOW+0)
/* The size of our dynamically allocated audio buffer */
#define AUDIOBUFSZ 64*2
/* How many flat-line sample before we trigger */
#define FLATLINE_SAMPLES 8
GHandle gwinCreateScope(GScopeObject *gs, coord_t x, coord_t y, coord_t cx, coord_t cy, uint32_t physdev, uint32_t frequency) {
/* Initialise the base class GWIN */
if (!(gs = (GScopeObject *)_gwinInit((GWindowObject *)gs, x, y, cx, cy, sizeof(GScopeObject))))
return 0;
/* Initialise the scope object members and allocate memory for buffers */
gs->gwin.type = GW_SCOPE;
gfxSemInit(&gs->bsem, 0, 1);
gs->nextx = 0;
if (!(gs->lastscopetrace = (coord_t *)gfxAlloc(gs->gwin.width * sizeof(coord_t))))
return 0;
if (!(gs->audiobuf = (adcsample_t *)gfxAlloc(AUDIOBUFSZ * sizeof(adcsample_t))))
return 0;
#if TRIGGER_METHOD == TRIGGER_POSITIVERAMP
gs->lasty = gs->gwin.height/2;
#elif TRIGGER_METHOD == TRIGGER_MINVALUE
gs->lasty = gs->gwin.height/2;
gs->scopemin = 0;
#endif
/* Start the GADC high speed converter */
gadcHighSpeedInit(physdev, frequency, gs->audiobuf, AUDIOBUFSZ, AUDIOBUFSZ/2);
gadcHighSpeedSetBSem(&gs->bsem, &gs->myEvent);
gadcHighSpeedStart();
return (GHandle)gs;
}
void gwinWaitForScopeTrace(GHandle gh) {
#define gs ((GScopeObject *)(gh))
int i;
coord_t x, y;
coord_t yoffset;
adcsample_t *pa;
coord_t *pc;
#if TRIGGER_METHOD == TRIGGER_POSITIVERAMP
bool_t rdytrigger;
int flsamples;
#elif TRIGGER_METHOD == TRIGGER_MINVALUE
bool_t rdytrigger;
int flsamples;
coord_t scopemin;
#endif
/* Wait for a set of audio conversions */
gfxSemWait(&gs->bsem, TIME_INFINITE);
/* Ensure we are drawing in the right area */
#if GDISP_NEED_CLIP
gdispSetClip(gh->x, gh->y, gh->width, gh->height);
#endif
yoffset = gh->height/2 + (1<<SCOPE_Y_BITS)/2;
x = gs->nextx;
pc = gs->lastscopetrace+x;
pa = gs->myEvent.buffer;
#if TRIGGER_METHOD == TRIGGER_POSITIVERAMP
rdytrigger = FALSE;
flsamples = 0;
#elif TRIGGER_METHOD == TRIGGER_MINVALUE
rdytrigger = FALSE;
flsamples = 0;
scopemin = 0;
#endif
for(i = gs->myEvent.count; i; i--) {
/* Calculate the new scope value - re-scale using simple shifts for efficiency, re-center and y-invert */
#if GADC_BITS_PER_SAMPLE > SCOPE_Y_BITS
y = yoffset - (*pa++ >> (GADC_BITS_PER_SAMPLE - SCOPE_Y_BITS));
#else
y = yoffset - (*pa++ << (SCOPE_Y_BITS - GADC_BITS_PER_SAMPLE));
#endif
#if TRIGGER_METHOD == TRIGGER_MINVALUE
/* Calculate the scopemin ready for the next trace */
if (y > scopemin)
scopemin = y;
#endif
/* Have we reached the end of a scope trace? */
if (x >= gh->width) {
#if TRIGGER_METHOD == TRIGGER_POSITIVERAMP || TRIGGER_METHOD == TRIGGER_MINVALUE
/* Handle triggering - we trigger on the next sample minimum (y value maximum) or a flat-line */
#if TRIGGER_METHOD == TRIGGER_MINVALUE
/* Arm when we reach the sample minimum (y value maximum) of the previous trace */
if (!rdytrigger && y >= gs->scopemin)
rdytrigger = TRUE;
#endif
if (y == gs->lasty) {
/* Trigger if we get too many flat-line samples regardless of the armed state */
if (++flsamples < FLATLINE_SAMPLES)
continue;
flsamples = 0;
} else if (y > gs->lasty) {
gs->lasty = y;
flsamples = 0;
#if TRIGGER_METHOD == TRIGGER_POSITIVERAMP
/* Arm the trigger when samples fall (y increases) ie. negative slope */
rdytrigger = TRUE;
#endif
continue;
} else {
/* If the trigger is armed, Trigger when samples increases (y decreases) ie. positive slope */
gs->lasty = y;
flsamples = 0;
if (!rdytrigger)
continue;
}
/* Ready for a the next trigger cycle */
rdytrigger = FALSE;
#endif
/* Prepare for a scope trace */
x = 0;
pc = gs->lastscopetrace;
}
/* Clear the old scope pixel and then draw the new scope value */
gdispDrawPixel(gh->x+x, gh->y+pc[0], gh->bgcolor);
gdispDrawPixel(gh->x+x, gh->y+y, gh->color);
/* Save the value */
*pc++ = y;
x++;
#if TRIGGER_METHOD == TRIGGER_POSITIVERAMP || TRIGGER_METHOD == TRIGGER_MINVALUE
gs->lasty = y;
#endif
}
gs->nextx = x;
#if TRIGGER_METHOD == TRIGGER_MINVALUE
gs->scopemin = scopemin;
#endif
#undef gs
}