Chuanshuoge: tinkercat timer interrupt clear on compare

Sunday, May 29, 2022

flash led every second with timer interrupt

volatile byte lightState = LOW;

int period;

void setup()

{

pinMode(9, OUTPUT);

TCCR1A = 0b00000000; //TCCR1A bit 0, 1 and TCCR1B bit 3, 4 set timer mode

TCCR1B = 0b00001101; //Set mode to be clear on compare. set scaler to be clock/1024

OCR1A = 15624; //period = (OCR1A/B + 1)*scaler*62.5ns = 1s

TIMSK1 = 0b00000010; //enable timer counter

sei();

Serial.begin(9600);

}

ISR (TIMER1_COMPA_vect){

lightState = digitalRead(9);

digitalWrite(9, not lightState);

period = TCNT1 *0.0000625*1024;

Serial.print("timer periord:");

Serial.println(period);

}

void loop()

{

}

reference:

Chuanshuoge