variable from TIM0_CAPT

Projects Programming
1

Hello Everyone,

I am now using Attiny10 and make following code with "TIM0_CAPT interrupt".
I hope to get variable change from "TIM0_CAPT interrupt" and enter "if(flgStart){}" but variable named "flgStart" might not be changed on interrupt part.

Is there any idea to improve this phenomena ?
I am looking for your reply.

/code/

#include <avr/io.h>
#include <avr/interrupt.h>
int flgTrig=1; //Flag for Capture Edge
int flgStart=1; //Flag from Interrupt

ISR(TIM0_CAPT_vect)
{
PORTB ^= (1<<0);
flgStart=1; //★flag is updated in this part
}

int main(void)
{
//Pin Assignment
//PB0 [O] toggled by TIM0_CAPT
//PB1 external PWM input

  • //PB2 [O] toggled by while(1)*
  • DDRB = (1<<2)| (0<<1)| (1<<0); //Data Direction (P76)*
  • PUEB = (0<<2)| (1<<1)| (0<<0); //Pull-Up Enable Control (P74)*
  • //Timer Interrupt*
  • TCCR0B |= (0 << ICES0); //The rising edge (P103)*
  • TIMSK0 |= (1 << ICIE0) ; //Enable Input Capture (P114)*
  • sei(); //Enable Global interrupt*
  • flgStart=0; //Init flag*
  • while (1)*
  • {*
  • if(flgStart){ //★But cannot enter if part*
  • PORTB ^= (1<<2);*
  • flgStart=0; //Reset flag*
  • }*
  • }*
    }
2

Variables used in interrupt service routines AND other functions MUST be declared volatile. Why isn't flgStart?

3

Not solving your problem but did you notice what your code looks like? Italics, strange symbols?

You can edit your post and
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4

Dear PaulS,

Thank you for your kind comment.
I try to declar "flgStart" with volatile.

Dear sterretje,

Thank you for your advice.
I will take care my font next time ...