*/
#include "watch_adc.h"
+#include "driver_init.h"
static void _watch_sync_adc(void) {
while (ADC->SYNCBUSY.reg);
_watch_sync_adc();
}
+static inline uint32_t _watch_adc_get_reference_voltage(const watch_adc_reference_voltage reference) {
+ switch (reference) {
+ case ADC_REFERENCE_INTREF:
+ return ADC_REFCTRL_REFSEL_INTREF_Val;
+ break;
+ case ADC_REFERENCE_VCC_DIV1POINT6:
+ return ADC_REFCTRL_REFSEL_INTVCC0_Val;
+ break;
+ case ADC_REFERENCE_VCC_DIV2:
+ return ADC_REFCTRL_REFSEL_INTVCC1_Val;
+ break;
+ case ADC_REFERENCE_VCC:
+ return ADC_REFCTRL_REFSEL_INTVCC2_Val;
+ break;
+ }
+}
+
void watch_set_analog_reference_voltage(watch_adc_reference_voltage reference) {
ADC->CTRLA.bit.ENABLE = 0;
if (reference == ADC_REFERENCE_INTREF) SUPC->VREF.bit.VREFOE = 1;
else SUPC->VREF.bit.VREFOE = 0;
- ADC->REFCTRL.bit.REFSEL = reference;
+ ADC->REFCTRL.bit.REFSEL = _watch_adc_get_reference_voltage(reference);
ADC->CTRLA.bit.ENABLE = 1;
_watch_sync_adc();
// throw away one measurement after reference change (the channel doesn't matter).
#include "watch.h"
-// matches adc.h
-#ifndef ADC_REFCTRL_REFSEL_INTREF_Val
-#define ADC_REFCTRL_REFSEL_INTREF_Val 0x0
-#endif
-
-#ifndef ADC_REFCTRL_REFSEL_INTVCC0_Val
-#define ADC_REFCTRL_REFSEL_INTVCC0_Val 0x1
-#endif
-
-#ifndef ADC_REFCTRL_REFSEL_INTVCC1_Val
-#define ADC_REFCTRL_REFSEL_INTVCC1_Val 0x2
-#endif
-
-#ifndef ADC_REFCTRL_REFSEL_INTVCC2_Val
-#define ADC_REFCTRL_REFSEL_INTVCC2_Val 0x5
-#endif
-
/** @addtogroup adc Analog Input
* @brief This section covers functions related to the SAM L22's analog-to-digital converter,
* as well as configuring and reading values from the five analog-capable pins on the
void watch_set_analog_sampling_length(uint8_t cycles);
typedef enum {
- ADC_REFERENCE_INTREF = ADC_REFCTRL_REFSEL_INTREF_Val,
- ADC_REFERENCE_VCC_DIV1POINT6 = ADC_REFCTRL_REFSEL_INTVCC0_Val,
- ADC_REFERENCE_VCC_DIV2 = ADC_REFCTRL_REFSEL_INTVCC1_Val,
- ADC_REFERENCE_VCC = ADC_REFCTRL_REFSEL_INTVCC2_Val,
+ ADC_REFERENCE_INTREF = 0,
+ ADC_REFERENCE_VCC_DIV1POINT6,
+ ADC_REFERENCE_VCC_DIV2,
+ ADC_REFERENCE_VCC,
} watch_adc_reference_voltage;