X-Git-Url: https://www.fi.muni.cz/~kas/git//home/kas/public_html/git/?p=tinyboard.git;a=blobdiff_plain;f=projects%2Fstep-up%2Fadc.c;h=55cd8610ab441cacc7663ddc8e605dde49869d7c;hp=ef714777011f1af24d171bb44cdd0d6461ac6b0e;hb=HEAD;hpb=edebb613b2f867d4f8473747744f329cb30e38fe diff --git a/projects/step-up/adc.c b/projects/step-up/adc.c index ef71477..55cd861 100644 --- a/projects/step-up/adc.c +++ b/projects/step-up/adc.c @@ -1,108 +1,69 @@ #include #include +#include +#include #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) +#define ZERO_ADC 2 -#define NUM_ADCS ZERO_ADC - -struct { - unsigned char read_zero_log : 2; - unsigned char read_drop_log : 2; - unsigned char read_keep_log : 4; -} adc_params[NUM_ADCS] = { - { 0, 1, PWMLED_ADC_SHIFT }, // pwmled 1 - { 0, 1, PWMLED_ADC_SHIFT }, // pwmled 2 - { 0, 1, PWMLED_ADC_SHIFT }, // pwmled 3 - { 0, 1, AMBIENT_ADC_SHIFT }, // ambient - { 0, 1, 0 }, // battery - { 0, 1, 0 }, // gain20 - { 0, 1, 0 }, // buttons -}; - -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; +//#define NUM_ADCS ZERO_ADC +#define NUM_ADCS 2 +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) { /* ADC numbering: PWM LEDs first, then others, zero at the end */ switch (n) { - case 0: // pwmled 1: 1.1V, ADC0,1 (PA0,1), gain 20 - ADMUX = _BV(REFS1) | _BV(MUX3) | _BV(MUX1) | _BV(MUX0); - break; - case 1: // pwmled 2: 1.1V, ADC2,1 (PA2,1), gain 20 - ADMUX = _BV(REFS1) | _BV(MUX3) | _BV(MUX2) | _BV(MUX1); - break; - case 2: // pwmled 3: 1.1V, ADC4 (PA5), single-ended - ADMUX = _BV(REFS1) | _BV(MUX2); - break; - case AMBIENT_ADC: // ambient light: 1.1V, ADC5 (PA6), single-ended - ADMUX = _BV(REFS1) | _BV(MUX2) | _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 + case 0: // pwmled 1: 1.1V, ADC3 (PB3), single-ended ADMUX = _BV(REFS1) | _BV(MUX1) | _BV(MUX0); break; - case ZERO_ADC: // zero: 1.1V, ADC1 (PA1), single-ended + 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; } } -static void start_next_adc() +void start_next_adc() { - 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; } -#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; - // we use the last iteration of zero_count to set up the MUX - // to its final destination, hence the "1 +" below: - if (adc_params[current_adc].read_zero_log) - zero_count = 1 + (1 << (adc_params[current_adc].read_zero_log-1)); - else - zero_count = 1; - - if (adc_params[current_adc].read_drop_log) - drop_count = 1 << (adc_params[current_adc].read_drop_log - 1); - else - drop_count = 0; - - read_count = 1 << adc_params[current_adc].read_keep_log; - n_reads_log = adc_params[current_adc].read_keep_log; // set up mux, start one-shot conversion - if (zero_count > 1) + if (read_zero) setup_mux(ZERO_ADC); else setup_mux(current_adc); @@ -110,6 +71,7 @@ static void start_next_adc() ADCSRA |= _BV(ADSC); } +#if 0 void timer_start_slow_adcs() { if (current_slow_adc > N_PWMLEDS) { // Don't start if in progress @@ -119,6 +81,7 @@ void timer_start_slow_adcs() // TODO: kick the watchdog here } } +#endif /* * Single synchronous ADC conversion. @@ -142,9 +105,13 @@ static uint16_t read_adc_sync() void init_adc() { - unsigned char i; - 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 @@ -153,22 +120,14 @@ void init_adc() // ADCSRB |= _BV(GSEL); // gain 8 or 32 // Disable digital input on all bits used by ADC - DIDR0 = _BV(ADC0D) | _BV(ADC1D) | _BV(ADC2D) | _BV(ADC3D) - | _BV(ADC4D) | _BV(ADC5D) | _BV(ADC6D); - - // 1.1V, ADC1,1, gain 20 + DIDR0 = _BV(ADC3D) | _BV(ADC2D); + + // 1.1V, GND ADMUX = _BV(REFS1) | _BV(MUX3) | _BV(MUX2) | _BV(MUX0); /* Do first conversion and drop the result */ read_adc_sync(); - adc1_gain20_offset = 0; - - for (i = 0; i < (1 << ADC1_GAIN20_OFFSET_SHIFT); i++) { - adc1_gain20_offset += read_adc_sync() - - (adc1_gain20_offset >> ADC1_GAIN20_OFFSET_SHIFT); - } - ADCSRA |= _BV(ADIE); // enable IRQ start_next_adc(); @@ -178,28 +137,18 @@ void susp_adc() { ADCSRA = 0; DIDR0 = 0; -} - -static void adc1_gain20_adc(uint16_t adcsum) -{ - // running average - adc1_gain20_offset += adcsum - - (adc1_gain20_offset >> ADC1_GAIN20_OFFSET_SHIFT); + power_adc_disable(); + adc_enabled = 0; } ISR(ADC_vect) { // IRQ handler uint16_t adcval = ADCW; - if (zero_count) { - if (zero_count > 1) { - ADCSRA |= _BV(ADSC); - zero_count--; - return; - } else { - setup_mux(current_adc); - zero_count = 0; - /* fall through */ - } + if (read_zero) { + setup_mux(current_adc); + read_zero = 0; + ADCSRA |= _BV(ADSC); // drop this one, start the next + return; } if (drop_count) { @@ -209,7 +158,7 @@ ISR(ADC_vect) { // IRQ handler } if (read_count) { - ADCSRA |= _BV(ADSC); + ADCSRA |= _BV(ADSC); // immediately start the next conversion adc_sum += adcval; read_count--; return; @@ -219,38 +168,15 @@ ISR(ADC_vect) { // IRQ handler * Now we have performed read_count measurements and have them * in adc_sum. */ - - // For inputs with gain, subtract the measured gain stage offset - if (current_adc < 2) { - uint16_t offset = adc1_gain20_offset - >> (ADC1_GAIN20_OFFSET_SHIFT - n_reads_log); - - if (adc_sum > offset) - adc_sum -= offset; - else - adc_sum = 0; - } - switch (current_adc) { case 0: - case 1: - case 2: - pwmled_adc(current_adc, adc_sum); + // pwmled_adc(current_adc, adc_sum); + pwmled_adc(adc_sum); break; - case AMBIENT_ADC: - ambient_adc(adc_sum); - break; - case BATTERY_ADC: + case 1: battery_adc(adc_sum); break; - case BUTTON_ADC: - button_adc(adc_sum); - break; - case ADC1_GAIN20: - adc1_gain20_adc(adcval); - break; } start_next_adc(); } -