Re: [avr-gcc-list] How to reserve registers

[Jens Bauer]

Hi Omar,


> .global IncrementCounter
> IncrementCounter:
>     ldi r19, 1                          ; use to increment with carry
>     clc
>     adc counter_b0, r19
>     adc counter_b1, r1
>     adc counter_b2, r1
>     adc counter_b3, r1
>     ret

I think you could get rid of clc, if the first instruction is changed to...

        add counter_b0,r19

You might also want to find a way to 'inline' the assembler code, but I don't 
know how time-critical the code is.
-If the TIMER2_COMPA_vect only contains the assembler code, I think you should 
consider making the entire interrupt routine in assembler, but ofcourse, that 
still depends on if you would benefit from it.
(RET spends 5 clock cycles, rcall spends another 4)


Love,
Jens