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Attiny25 and OC0A in normal mode.
I have set Timer0 in normal mode. Output compare A is working, ISR(IMER0_COMPA_vect) can occur, but pin PB0(OC0A) can’t set on compare match, always is low.
from pdf:
COM0A1:0 bit functionality when the WGM02:0 bits are set to a normal or CTC mode (non-PWM).
COM01 COM00 Description
1 1 Set OC0A on Compare MatchWhat is wrong with OC0A ?
Code:
ISR(TIMER0_OVF_vect)
{
}ISR(TIMER0_COMPA_vect) //SIG_OUTPUT_COMPARE1A
{
}void setup(void)
{
DDRB |= (1ltltPB0); //PB0(OC0A) = out
PORTB=0xFE; //PB0 without pullupTCCR0B |= (1ltltCS01); //preskaler 8 1000 ticks = 1us
TCCR1 amp= ~(1ltltTOIE0); //clear tim0 ovr flag
TIMSK |= (1ltltTOIE0); //timer 0 overflowOCR0A = 255 – 25; //pulse 25us
TCCR0A |= (1ltltCOM0A1) + (1ltltCOM0A0); //Set OC0A on Compare Match
TIMSK |= (1ltltOCIE0A); //Output Compare Match A Interrupt Enable
TCCR0B |= (1ltltFOC0A); //Force Output Compare A
TIMSK |= (1ltltOCIE0A); //Output Compare Match A Interrupt Enablesei();
}int main(void)
{
setup();while(1)
{}
return 0;
}
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