AVR-Chat

You're not showing where you declared "seconds" but make it volatile and it will work:
 
volatile uint8_t seconds;
 
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> To: AVR-Chat@yahoogroups.com
> From: ajellisuk@yahoo.co.uk
> Date: Sat, 8 May 2010 17:54:29 +0000
> Subject: [AVR-Chat] My timer does not seem to be incrementing an integer
>
> Hi,
>
> I have a project using an Atmega16 where the timer should be interrupting once a second, but my sconds variable in not being incremented. If I use this line:
>
> PORTD = ~PORTD;
>
> The leds connected to that port flash, if I write my seconds variable to that port only bianry one is indicated, whcih suggests to me that the timer is not running or the firmware is being reset.
>
> Could someone shed some light on this for me please? I have disabled the watch dog timer too My code is below:
>
> Andrew
>
> const uint16_t interval = 4000000/65536;//Work out interval from CPU frequency
>
> void Init_Timer1()
> {
> // Set up counter. Fclk = 4Mz
> TCCR1B = 1 << WGM12 | 1 << CS12; // Fclk / 256, clear on match
> OCR1A = interval; // Timer ticks at 4000000/(256*interval) (1s)
> TIMSK |= (1 << OCIE1A | 1 << TOIE1);
> asm("sei");
> }
>
> ISR(TIMER1_COMPA_vect)
> {
> wdt_reset();
> power_save_timer++;
> seconds = seconds+1;
> PORTD = seconds << 2;// Used to verify timer is running
>
> if (seconds>59)
> {
> seconds=0;
> minutes++;
> }
>
> if(minutes>59)
> {
> minutes=0;
> hours++;
> }
>
> if(hours>23) hours=0;
> }
>
>
>
>
> ------------------------------------
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