Experimental step-up driver for chain of 5630 LEDs.

[tinyboard.git] / projects / step-up / adc.c

diff --git a/projects/step-up/adc.c b/projects/step-up/adc.c
index d7679d30b09cff20d7038629cca4d334b8a04b06..55cd8610ab441cacc7663ddc8e605dde49869d7c 100644 (file)
--- a/projects/step-up/adc.c
+++ b/projects/step-up/adc.c
@@ -1,16 +1,20 @@
 #include <avr/io.h>
 #include <avr/interrupt.h>
+#include <avr/power.h>
 #include <avr/sleep.h>
 
 #include "lights.h"
 
-#define ZERO_ADC    1
+#define ZERO_ADC    2
 
 //#define NUM_ADCS     ZERO_ADC
-#define NUM_ADCS       1
+#define NUM_ADCS       2
 
-volatile static unsigned char current_adc, current_slow_adc;
+volatile static unsigned char current_adc;
+volatile unsigned char adc_enabled;
+volatile unsigned char need_battery_adc, need_pwmled_adc;
 static uint16_t adc_sum, read_zero, drop_count, read_count, n_reads_log;
+volatile uint16_t jiffies;
 
 static void setup_mux(unsigned char n)
 {
@@ -19,6 +23,9 @@ static void setup_mux(unsigned char n)
        case 0: // pwmled 1: 1.1V, ADC3 (PB3), single-ended
                ADMUX = _BV(REFS1) | _BV(MUX1) | _BV(MUX0);
                break;
+       case 1: // battery voltage: 1.1V, ADC1 (PB2), single-ended
+               ADMUX = _BV(REFS1) | _BV(MUX0);
+               break;
        case ZERO_ADC: // zero: 1.1V, GND, single-ended
                ADMUX = _BV(REFS1) | _BV(MUX3) | _BV(MUX2) | _BV(MUX0);
                break;
@@ -27,37 +34,33 @@ static void setup_mux(unsigned char n)
 
 void start_next_adc()
 {
-#if 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;
+       if (need_battery_adc) {
+               need_battery_adc = 0;
+               current_adc = 1;
+               read_zero = 1;
+               drop_count = 1;
+               read_count = 1;
+               n_reads_log = 0;
+       } else if (need_pwmled_adc) {
+               current_adc = 0;
+               read_zero = 0;
+               drop_count = 1;
+               read_count = 1 << PWMLED_ADC_SHIFT;
+               n_reads_log = PWMLED_ADC_SHIFT;
        } else {
-               // next PWMLED
-               current_adc--;
+               ADCSRA &= ~_BV(ADEN);
+               power_adc_disable();
+               adc_enabled = 0;
+               return;
        }
-#else
-       // single ADC for testing only
-       current_adc = 0;
-#endif
 
-#if 0
-       log_byte(0x90 + current_adc); // debug ADC switching
-#endif
+       if (!adc_enabled) {
+               power_adc_enable();
+               ADCSRA |= _BV(ADEN);
+               adc_enabled = 1;
+       }
 
        adc_sum = 0;
-       read_zero = 0;
-       drop_count = 1;
-
-       read_count = 1 << PWMLED_ADC_SHIFT;
-       n_reads_log = PWMLED_ADC_SHIFT;
 
        // set up mux, start one-shot conversion
        if (read_zero)
@@ -102,8 +105,13 @@ static uint16_t read_adc_sync()
 
 void init_adc()
 {
-       current_slow_adc = NUM_ADCS;
+       need_battery_adc = 0;
+       need_pwmled_adc = 0;
        current_adc = 0;
+       adc_enabled = 1;
+
+       power_adc_enable();
+       ACSR |= _BV(ACD);       // but disable the analog comparator
 
        ADCSRA = _BV(ADEN)                      // enable
                | _BV(ADPS1) | _BV(ADPS0)       // CLK/8 = 125 kHz
@@ -125,21 +133,14 @@ void init_adc()
        start_next_adc();
 }
 
-#if 0
 void susp_adc()
 {
        ADCSRA = 0;
        DIDR0 = 0;
+       power_adc_disable();
+       adc_enabled = 0;
 }
 
-static void adc1_gain20_adc(uint16_t adcsum)
-{
-       // running average
-       adc1_gain20_offset += adcsum
-                       - (adc1_gain20_offset >> ADC1_GAIN20_OFFSET_SHIFT);
-}
-#endif
-
 ISR(ADC_vect) { // IRQ handler
        uint16_t adcval = ADCW;
 
@@ -172,6 +173,9 @@ ISR(ADC_vect) { // IRQ handler
                // pwmled_adc(current_adc, adc_sum);
                pwmled_adc(adc_sum);
                break;
+       case 1:
+               battery_adc(adc_sum);
+               break;
        }
 
        start_next_adc();