#include "lights.h"
-#define AMBIENT_ADC N_PWMLEDS
-#define BATTERY_ADC (N_PWMLEDS + 1)
-#define ADC1_GAIN20 (N_PWMLEDS + 2)
-#define BUTTON_ADC (N_PWMLEDS + 3)
-#define ZERO_ADC (N_PWMLEDS + 4)
+// pwmleds are measured continuously (when active)
+#define AMBIENT_ADC N_PWMLEDS // measured every jiffy (16 Hz)
+#define BUTTON_ADC (N_PWMLEDS + 1) // measured every jiffy (16 Hz)
+#define FIRST_16HZ_ADC BUTTON_ADC
+#define BATTERY_ADC (N_PWMLEDS + 2) // once per second
+#define ADC1_GAIN20 (N_PWMLEDS + 3) // once per second
+#define FIRST_1S_ADC ADC1_GAIN20
+#define ZERO_ADC (N_PWMLEDS + 4) // must be last
#define NUM_ADCS ZERO_ADC
{ 0, 1, PWMLED_ADC_SHIFT }, // pwmled 1
{ 0, 1, PWMLED_ADC_SHIFT }, // pwmled 2
{ 0, 1, PWMLED_ADC_SHIFT }, // pwmled 3
- { 0, 1, 3 }, // ambient
+ { 0, 1, AMBIENT_ADC_SHIFT }, // ambient
+ { 0, 1, 0 }, // buttons
{ 0, 1, 0 }, // battery
{ 0, 1, 0 }, // gain20
- { 0, 1, 0 }, // buttons
};
-volatile static unsigned char current_adc;
+volatile unsigned char adc_is_on;
+
+volatile static unsigned char current_adc, slow_adcs_wanted;
static uint16_t adc_sum, zero_count, drop_count, read_count, n_reads_log;
#define ADC1_GAIN20_OFFSET_SHIFT 6
static uint16_t adc1_gain20_offset;
case AMBIENT_ADC: // ambient light: 1.1V, ADC5 (PA6), single-ended
ADMUX = _BV(REFS1) | _BV(MUX2) | _BV(MUX0);
break;
+ case BUTTON_ADC: // buttons: 1.1V, ADC3, single-ended
+ PORTA |= _BV(PA3); // +5V to the voltage splitter
+ ADMUX = _BV(REFS1) | _BV(MUX1) | _BV(MUX0);
+ break;
case BATTERY_ADC: // batt voltage: 1.1V, ADC6 (PA7), single-ended
ADMUX = _BV(REFS1) | _BV(MUX2) | _BV(MUX1);
break;
case ADC1_GAIN20: // gain stage offset: 1.1V, ADC1,1, gain 20
ADMUX = _BV(REFS1) | _BV(MUX3) | _BV(MUX2) | _BV(MUX0);
break;
- case BUTTON_ADC: // buttons: 1.1V, ADC3, single-ended
- PORTA |= _BV(PA3); // +5V to the voltage splitter
- ADMUX = _BV(REFS1) | _BV(MUX1) | _BV(MUX0);
- break;
case ZERO_ADC: // zero: 1.1V, ADC1 (PA1), single-ended
ADMUX = _BV(REFS1) | _BV(MUX0);
break;
static void start_next_adc()
{
- if (current_adc > 0)
+ if (slow_adcs_wanted) {
+ current_adc = slow_adcs_wanted;
+ slow_adcs_wanted = 0;
+ goto found;
+ }
+
+ if (current_adc > N_PWMLEDS) {
current_adc--;
- else
- // TODO: kick the watchdog here.
- current_adc = NUM_ADCS-1;
+ goto found;
+ }
+
+ if (!TIMER1_IS_ON()) {
+ adc_is_on = 0;
+ return;
+ }
+
+ do {
+ if (!current_adc)
+ current_adc = N_PWMLEDS;
+ --current_adc;
+ } while (!PWM_IS_ON(current_adc));
+
+found:
+ adc_is_on = 1;
adc_sum = 0;
// we use the last iteration of zero_count to set up the MUX
ADCSRA |= _BV(ADSC);
}
+void timer_start_slow_adcs()
+{
+ if ((jiffies & 0x000F) == 0) {
+ slow_adcs_wanted = FIRST_1S_ADC;
+ } else {
+ slow_adcs_wanted = FIRST_16HZ_ADC;
+ }
+
+ if (!adc_is_on) {
+ start_next_adc();
+ }
+}
+
/*
* Single synchronous ADC conversion.
* Has to be called with IRQs disabled (or with the ADC IRQ disabled).
void init_adc()
{
unsigned char i;
- current_adc = NUM_ADCS;
+ current_adc = 0;
+ adc_is_on = 1;
ADCSRA = _BV(ADEN) // enable
| _BV(ADPS1) | _BV(ADPS0) // CLK/8 = 125 kHz
case AMBIENT_ADC:
ambient_adc(adc_sum);
break;
- case BATTERY_ADC:
- battery_adc(adc_sum);
- break;
case BUTTON_ADC:
button_adc(adc_sum);
break;
+ case BATTERY_ADC:
+ battery_adc(adc_sum);
+ break;
case ADC1_GAIN20:
adc1_gain20_adc(adcval);
break;