gbngfdbjn

main.c

@@ -6,43 +6,100 @@
 #include <stdbool.h>
 #include <avr/interrupt.h>
 
-volatile int debounce_int2 = 10;
+volatile uint16_t tick_timer_start = 0xffff - (F_CPU / 1024 / 1000);
-volatile int debounce_int3 = 10;
+volatile bool speaker_disabled = true;
 
-ISR(INT2_vect) {
+uint16_t notes[][3] = {
-    if (debounce_int2) return;
+    { 1000, 200, 30 },
-    debounce_int2 = 100;
+    { 1200, 200, 30 },
-    OCR0A++;
+    { 1500, 200, 30 },
+    { 1600, 200, 30 },
+    { 1500, 200, 30 },
+    { 1200, 100, 10 },
+    { 1000, 300, 100 },
+};
+
+void ADC_Setup() {
+    // AVCC with external capacitor at AREF pin
+    ADMUX = _BV(REFS0);
+
+    // Enable ADC, set prescaler to 8tick_timer_start
+    ADCSRA = _BV(ADEN) | _BV(ADPS0) | _BV(ADPS1);
+
+    // Perform dummy readout
+    ADCSRA |= _BV(ADSC); // Start conversion
+    while (ADCSRA & _BV(ADSC)); // Await result
+    (void) ADCW; // Read out result
 }
 
-ISR(INT3_vect) {
+uint16_t ADC_Read(uint8_t channel) {
-    if (debounce_int3) return;
+    // Select chosen channel
-    debounce_int3 = 100;
+    ADMUX = (ADMUX & ~(0x1F)) | (channel & 0x1F);
-    OCR0A--;
+    // Start conversion
+    ADCSRA |= _BV(ADSC);
+    // Await the result
+    while (ADCSRA & _BV(ADSC));
+    // Although it doesn't appear to be documented, ADCW holds the covnersion result
+    return ADCW;
 }
 
-ISR(TIMER0_COMPA_vect) {
+uint16_t ADC_Read_Avg(uint8_t channel, uint8_t samples) {
-    PORTF ^= 0b00000001;
+    uint32_t sum = 0;
+    for (int i = 0; i < samples; i++) {
+        sum += ADC_Read(channel);
+    }
+    return (uint16_t)(sum / samples);
+}
+
+void TIMER_Setup() {
+    TCCR1B |= _BV(CS10) | _BV(CS12); // clk/1024
+
+    // Set the TOIE (Timer Overflow Interrupt Enable) bit
+    // on TIMSK1 (Timer 1 Interrupt Mask Register).
+    TIMSK1 |= _BV(TOIE1);
+
+    // Sets the current timer value
+    TCNT1 = tick_timer_start;
+
+    // Enable interrupts
+    sei();
+}
+
+// ISR is used to handle interrupts. TIMER1_OVF_vect
+// is triggered whenever timer 1 (16 bit) overflows.
+ISR(TIMER1_OVF_vect) {
+    TCNT1 = tick_timer_start;
+    PORTB ^= 0b10000000;
+
+    if (speaker_disabled) PORTK &= 0b11111110;
+    else PORTK ^= 0b00000001;
+}
+
+void play_note(uint16_t freq, uint8_t delay, uint8_t delay_silence) {
+    speaker_disabled = false;
+    tick_timer_start = 0xffff - (F_CPU / freq / 1000);
+    for (int i = 0; i < delay; i++) _delay_ms(1);
+    speaker_disabled = true;
+    for (int i = 0; i < delay_silence; i++) _delay_ms(1);
 }
 
 void main() {
-    DDRF = 0b00000001;
+    DDRK = 0b00000001;
-    DDRD = 0b00000000;
+    PORTB = 0b10000000; // Start with LED enabled
-    PORTD |= 0b00001100;
 
-    // EIMSK controls which ports can trigger interrupts
+    ADC_Setup();
-    EIMSK |= _BV(INT2) | _BV(INT3);
+    TIMER_Setup();
-    // Trigger on falling edge on INT2 and INT3
-    EICRA |= _BV(ISC21) | _BV(ISC31);
 
-    TCCR0B |= _BV(CS00) | _BV(CS02); // clk/1024
+    long rows = sizeof(notes) / sizeof(notes[0]);
-    TIMSK0 |= _BV(OCIE0A);
-    OCR0A = 0;
 
-    sei();
+    while (true) {
+        for (int i = 0; i < rows; i++) {
+            play_note(notes[i][0], notes[i][1], notes[i][2]);
+        }
 
-    while(1) {
+        //uint16_t value = ADC_Read_Avg(0, 4);
-        _delay_ms(10);
+        //speaker_disabled = value == 0;
-        OCR0A++;
+        //if  (value < 100) value = 100; // Anything lower than this causes issues
+        //tick_timer_start = 0xffff - (F_CPU / value / 1000);
     }
 }