[avr-gcc-list] efficient Timer Interrupts

[Torsten Hahn]

Hi,

i have an application where i want do stuff in an timer interrupt, but 
i want do the stuff only n times. So a solution would be the following:


volatile uint16_t cnt = 10000;


SIGNAL(SIG_OUTPUT_COMPARE0)
{
        // do stuff, e.g.
        // read data from an extern adc
        // accumulate data ...

        if(cnt--) {
                // stop the timer0 / interrupt and set an "ready" flag
        }
}

The problem for me is, that using an extern (ram) var as a counter 
consumes much processor cycles (loading the var from ram, decrementing, 
write back). Is there a better (faster) solution ? Iam looking for a 
way to stop for example the timer 0 exactly after  a given number of 
executions.

Any Ideas ?

thx,
Torsten.