ugfx/drivers/gadc/AT91SAM7/gadc_lld.c
2013-06-15 21:37:22 +10:00

89 lines
2.3 KiB
C

/*
* This file is subject to the terms of the GFX License. If a copy of
* the license was not distributed with this file, you can obtain one at:
*
* http://chibios-gfx.com/license.html
*/
/**
* @file drivers/gadc/AT91SAM7/gadc_lld.c
* @brief GADC - Periodic ADC driver source file for the AT91SAM7 cpu.
*
* @defgroup Driver Driver
* @ingroup GADC
* @{
*/
#include "gfx.h"
#if GFX_USE_GADC
#include "gadc/lld/gadc_lld.h"
static ADCConversionGroup acg = {
FALSE, // circular
1, // num_channels
GADC_ISR_CompleteI, // end_cb
GADC_ISR_ErrorI, // error_cb
0, // channelselects
0, // trigger
0, // frequency
};
void gadc_lld_init(void) {
adcStart(&ADCD1, NULL);
}
size_t gadc_lld_samples_per_conversion(uint32_t physdev) {
size_t cnt;
int i;
/* The AT91SAM7 has AD0..7 - physdev is a bitmap of those channels */
for(cnt = 0, i = 0; i < 8; i++, physdev >>= 1)
if (physdev & 0x01)
cnt++;
return cnt;
}
void gadc_lld_start_timer(uint32_t physdev, uint32_t frequency) {
(void) physdev;
/**
* The AT91SAM7 ADC driver supports triggering the ADC using a timer without having to implement
* an interrupt handler for the timer. The driver also initialises the timer correctly for us.
* Because we aren't trapping the interrupt ourselves we can't increment GADC_Timer_Missed if an
* interrupt is missed.
*/
acg.frequency = frequency;
}
void gadc_lld_stop_timer(uint32_t physdev) {
(void) physdev;
if ((acg.trigger & ~ADC_TRIGGER_SOFTWARE) == ADC_TRIGGER_TIMER)
adcStop(&ADCD1);
}
void gadc_lld_adc_timerI(GadcLldTimerData *pgtd) {
/**
* We don't need to calculate num_channels because the AT91SAM7 ADC does this for us.
*/
acg.channelselects = pgtd->physdev;
acg.trigger = pgtd->now ? (ADC_TRIGGER_TIMER|ADC_TRIGGER_SOFTWARE) : ADC_TRIGGER_TIMER;
adcStartConversionI(&ADCD1, &acg, pgtd->buffer, pgtd->count);
/* Next time assume the same (still running) timer */
acg.frequency = 0;
}
void gadc_lld_adc_nontimerI(GadcLldNonTimerData *pgntd) {
/**
* We don't need to calculate num_channels because the AT91SAM7 ADC does this for us.
*/
acg.channelselects = pgntd->physdev;
acg.trigger = ADC_TRIGGER_SOFTWARE;
adcStartConversionI(&ADCD1, &acg, pgntd->buffer, 1);
}
#endif /* GFX_USE_GADC */
/** @} */