X-Git-Url: https://www.fi.muni.cz/~kas/git//home/kas/public_html/git/?p=bike-lights.git;a=blobdiff_plain;f=firmware%2Fadc.c;h=c6b113d4932cb538768fb8f94674d53af34a2483;hp=02af6b380724ae6f92ccca9407d1e1951a75c53f;hb=5d0ab95bb20a304693c1e0ec6c7900b7090d03e2;hpb=4c6ff89995f620aadb6cd8ef9403adac8ef48478

diff --git a/firmware/adc.c b/firmware/adc.c
index 02af6b3..c6b113d 100644
--- a/firmware/adc.c
+++ b/firmware/adc.c
@@ -3,11 +3,12 @@
 
 #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 BATTERY_ADC (N_PWMLEDS + 2)	// once per second
+#define ADC1_GAIN20 (N_PWMLEDS + 3)	// once per second
+#define ZERO_ADC    (N_PWMLEDS + 4)	// must be last
 
 #define NUM_ADCS	ZERO_ADC
 
@@ -19,13 +20,13 @@ struct {
 	{ 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 static unsigned char current_adc, current_slow_adc;
 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;
@@ -47,16 +48,16 @@ static void setup_mux(unsigned char n)
 	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;
@@ -65,11 +66,25 @@ static void setup_mux(unsigned char n)
 
 static void start_next_adc()
 {
-	if (current_adc > 0)
+	if (current_adc == 0) {
+		if (current_slow_adc > N_PWMLEDS) {
+			// read one of the non-PWMLED ADCs
+			current_adc = --current_slow_adc;
+		} else {
+			// no more non-PWMLEDs to do, start with PWMLEDs
+			current_adc = N_PWMLEDS-1;
+		}
+	} else if (current_adc >= N_PWMLEDS) {
+		// one of the non-PWMLED ADCs just finished, skip to PWMLEDs.
+		current_adc = N_PWMLEDS-1;
+	} else {
+		// next PWMLED
 		current_adc--;
-	else
-		// TODO: kick the watchdog here.
-		current_adc = NUM_ADCS-1;
+	}
+
+#if 0
+	log_byte(0x90 + current_adc); // debug ADC switching
+#endif
 
 	adc_sum = 0;
 	// we use the last iteration of zero_count to set up the MUX
@@ -96,6 +111,16 @@ static void start_next_adc()
 	ADCSRA |= _BV(ADSC);
 }
 
+void timer_start_slow_adcs()
+{
+	if (current_slow_adc > N_PWMLEDS) { // Don't start if in progress
+		log_byte(0x80 + current_slow_adc);
+	} else {
+		current_slow_adc = NUM_ADCS;
+		// TODO: kick the watchdog here
+	}
+}
+
 /*
  * Single synchronous ADC conversion.
  * Has to be called with IRQs disabled (or with the ADC IRQ disabled).
@@ -119,7 +144,8 @@ static uint16_t read_adc_sync()
 void init_adc()
 {
 	unsigned char i;
-	current_adc = NUM_ADCS;
+	current_slow_adc = NUM_ADCS;
+	current_adc = 0;
 
 	ADCSRA = _BV(ADEN)			// enable
 		| _BV(ADPS1) | _BV(ADPS0)	// CLK/8 = 125 kHz
@@ -215,12 +241,12 @@ ISR(ADC_vect) { // IRQ handler
 	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;