zaujimavost pri programovani AVR v GCC

[Petr Simek]

On Tue, 23 Oct 2007, Richard Kaliciak wrote:

> 	while(1){
> 		PORTA = counter++;
>    d2:	8b bb       	out	0x1b, r24	; 27
>    d4:	01 96       	adiw	r24, 0x01	; 1
>    d6:	fd cf       	rjmp	.-6      	; 0xd2 <main+0x4>
> ---------- end ----------
> (counter je v R24 a R25 = 16 bitov)

> 	while(1){
> 		counter++;
>    d0:	8f 5f       	subi	r24, 0xFF	; 255
> 		PORTA = counter;
>    d2:	8b bb       	out	0x1b, r24	; 27
>    d4:	fd cf       	rjmp	.-6      	; 0xd0 <main+0x2>
> ---------- end ----------
> (counter je v R24 = 8 bitov)

> Vie mi to niekto vysvetlit?

Vysvetlit to neumim, ale mam pocit ze obe ty smycky jsou stejne rychle.
Jediny rozdil je v te pocatecni inicializaci. To zpomaleni poznate ?

> Richard Kaliciak

*------------------------------------------------------------------------*
|                          Petr Simek   APS JU                           |
|                             psimek@jcu.cz                              |
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