#include <avr/io.h>
+#include <avr/eeprom.h>
#include <util/delay.h>
+#include <avr/sleep.h>
+#include <avr/interrupt.h>
+
+volatile uint16_t adcval;
+unsigned char led_is_on = 0;
+volatile unsigned char adccount = 0;
+
+typedef struct {
+ unsigned char pwmval, expected;
+} led_level_t;
+
+led_level_t led_modes[2] = {
+ { 0x50, 0x38 },
+ { 0x38, 0x04 },
+};
+
+unsigned char led_mode = 0;
+unsigned char led_mode_changed = 0;
+
+static void inline led_on()
+{
+ DDRB |= _BV( PB5 );
+ PORTA |= _BV( PA0 );
+ led_is_on = 1;
+}
+
+static void inline led_off()
+{
+ led_is_on = 0;
+ DDRB &= ~_BV( PB5 );
+ PORTA &=~ _BV( PA0 );
+// ADCSRA &= ~(_BV(ADIE) | _BV(ADIF));
+}
+
+/* ------------ Logging/Debugging ----------- */
+
+unsigned char debug_state EEMEM;
+
+static void inline debug_setstate(unsigned char val)
+{
+ eeprom_write_byte(&debug_state, val);
+}
+
+#define LOG_BUFFER 64
+uint16_t log_buffer[LOG_BUFFER] EEMEM;
+unsigned char log_buffer_count;
+uint16_t log_buffer2[LOG_BUFFER];
+volatile unsigned char stop = 0;
+
+static void inline init_log()
+{
+ debug_setstate(1);
+ log_buffer_count = 0;
+}
+
+static void log_word(uint16_t word) {
+ if (log_buffer_count >= LOG_BUFFER)
+ return;
+
+ // eeprom_write_word(&log_buffer[log_buffer_count], word);
+ log_buffer2[log_buffer_count] = word;
+ log_buffer_count++;
+
+ if (log_buffer_count == LOG_BUFFER) {
+ unsigned char i;
+ for (i=0; i < LOG_BUFFER; i++) {
+ eeprom_write_word(&log_buffer[i],
+ log_buffer2[i]);
+ }
+ debug_setstate(0x42);
+ }
+}
+
+/* ------------ Timer ----------- */
+
+volatile uint16_t jiffies = 0;
+
+static void inline init_tmr()
+{
+ TCCR0A = _BV(WGM00);
+ TCCR0B = _BV(CS02) | _BV(CS00); // 1 kHz
+ OCR0A = 12; // 100 Hz
+ TIMSK |= _BV(OCIE0A);
+ DDRA |= _BV( PA0 );
+
+ jiffies = 0;
+}
+
+static void inline tmr_handler()
+{
+ unsigned char c = jiffies & 0x0F;
+ unsigned char c1 = jiffies & 0x7F;
+
+ ++jiffies;
+
+#if 0
+ if (c == 1)
+ led_on();
+
+ if (c == 9)
+ led_off();
+#endif
+
+ if (c == 0x02 || c == 0x08)
+ led_on();
+
+ if (c == 0x05 || c == 0x0b)
+ led_off();
+
+#if 1
+ if (c1 == 0x10) {
+ led_mode = 0;
+ led_mode_changed = 1;
+ OCR1D = led_modes[led_mode].pwmval;
+ } else if (c1 == 0x70) {
+ led_mode = 1;
+ led_mode_changed = 1;
+ OCR1D = led_modes[led_mode].pwmval;
+ }
+#endif
+
+ ADCSRA |= _BV(ADSC);
+#if 0
+ if (led_is_on && adcval != 0xFFEE) {
+ adcval = 0xFFEE;
+
+ ADCSRA |= _BV(ADIF) | _BV(ADIE) | _BV(ADSC);
+ }
+#endif
+}
+
+ISR(TIMER0_COMPA_vect)
+{
+ tmr_handler();
+}
+
+/* ------------ PWM ----------- */
+
+static void inline init_pwm()
+{
+ /* Async clock */
+ PLLCSR = _BV(LSM) | _BV(PLLE);
+ _delay_ms(1);
+ while (PLLCSR & _BV(PLOCK) == 0)
+ ;
+ PLLCSR |= _BV(PCKE);
+
+ TCCR1C = _BV(COM1D0) | _BV(COM1D1) | _BV(PWM1D);
+ TCCR1A = _BV(COM1A0) | _BV(COM1A1) | _BV(COM1B0) | _BV(COM1B1) | _BV(PWM1A) | _BV(PWM1B);
+ // TCCR1B = 0x80| _BV(CS13) | _BV(CS11);
+ TCCR1B = _BV(7) // PWM1X: PWM inversion mode
+ | _BV(CS10) // no clock prescaling
+ ;
+ OCR1C = 0xFF; // TOP value
+ OCR1D = OCR1B = OCR1A = 0;
+ // OCR1D = 0;
+ DDRB |= _BV( PB5 );
+ PORTB &= ~(_BV( PB5 ) | _BV( PB1 ) | _BV( PB3 ));
+
+ // led_off();
+ // TIMSK |= _BV(TOIE1);
+}
+
+#if 0
+static void inline pwm_handler()
+{
+ // TIMSK &= ~_BV(TOIE1);
+ // OCR1D = pwmval;
+}
+
+ISR(TIMER1_OVF_vect)
+{
+ pwm_handler();
+}
+#endif
+
+/* ------------ A/D Converter ----------- */
+
+static void inline init_adc()
+{
+ ADCSRA = _BV(ADEN) // enable
+ | _BV(ADPS1) | _BV(ADPS0) // CLK/8 = 125 kHz
+ // | _BV(ADPS2) // CLK/16 = 62.5 kHz
+ ;
+ ADMUX = _BV(REFS1) // 1.1V internal reference
+ | _BV(MUX4)|_BV(MUX3) // port ADC5-6, gain 1
+ ;
+ // ADCSRB = _BV(REFS2);
+ ADCSRB |= _BV(GSEL);
+ // Disable digital input on all bits used by ADC
+ DIDR0 = _BV(ADC5D)|_BV(ADC6D) | _BV(AREFD);
+ ADCSRA |= _BV(ADIE);
+}
+
+static void inline adc_handler()
+{
+ uint16_t new_pwm = led_modes[led_mode].pwmval;
+ uint16_t old_pwm = new_pwm;
+ uint16_t adc_exp = led_modes[led_mode].expected;
+
+ adcval = ADCW;
+ adccount++;
+
+ // log_word(((adcval & 0x3FC) << 6) | pwmval);
+
+ if (!led_is_on)
+ return;
+
+ // ADCSRA &= ~(_BV(ADIE) | _BV(ADIF));
+
+ if (led_mode_changed) {
+ led_mode_changed = 0;
+ goto set_pwm;
+ }
+
+ log_word(((adcval & 0xFF) << 8) | old_pwm);
+
+ if (2*adcval > 5*adc_exp) { // >2.5x expected, lower significantly
+ new_pwm = 2*old_pwm/3;
+ } else if (3*adcval > 4*adc_exp) { // >1.33x expected, lower a bit
+ new_pwm = old_pwm - 1;
+ } else if (4*adcval < 3*adc_exp) { // 0.75x expected, raise a bit
+ new_pwm = old_pwm + 1;
+ }
+
+ if (new_pwm > 0x60) { // odpojeno?
+ new_pwm = 0x60;
+ }
+ if (new_pwm < 2) { // zkrat?
+ new_pwm = 2;
+ }
+
+set_pwm:
+ if (new_pwm != old_pwm) {
+ led_modes[led_mode].pwmval = new_pwm;
+ OCR1D = new_pwm;
+ }
+ // ADCSRA |= _BV(ADSC);
+}
+
+ISR(ADC_vect)
+{
+ adc_handler();
+}
int main(void)
{
- DDRA |= _BV( PA0 );
- while( 1 ) {
- PORTA |= _BV( PA0 );
- _delay_ms(2000);
- PORTA &=~ _BV( PA0 );
- _delay_ms(2000);
- }
+ _delay_ms(1500);
+ init_log();
+
+ init_pwm();
+ init_adc();
+ init_tmr();
+
+ led_on();
+ debug_setstate(3);
+
+ sei();
+ while (1)
+ ; // sleep_mode();
+
+#if 0
+ while (1) {
+ PORTA |= _BV( PA0 );
+ _delay_ms(200);
+ PORTA &=~ _BV( PA0 );
+ _delay_ms(200);
+ }
+#endif
}