I stand corrected. It's not often that you need to check for Z result after a clr. I always thought it was a way of clearing a register while preserving SREG (since the programmer will know what the result will be anyway) I guess you would use [ldi 0x00] for that
mrtangent wrote: > > Yes, CLR affects SREG (S, V, N, Z). > > See <http://www.atmel.com/dyn/resources/prod_documents/doc0856.pdf> > page 11 (Instruction Set Summary) > page 54 (CLR – Clear Register) > > CLR is just a convenient shorthand for EOR, where the two operands happen > to be the same register. > > Cheers, > > --Dave > > On Aug 14, 2010, at 1:39 AM, darkschine wrote: > >> >> Are you sure that "clr" has an impact on SREG? I think you should double >> check... >> >> >> Johannes Bauer wrote: >>> >>> On 12.08.2010 18:13, Johannes Bauer wrote: >>> >>>> This appears to be strange to me. The "clr r1" instruction should IMO >>>> be >>>> placed after the first "push r0" instruction. >>> >>> You are wrong, Johannes. It appears to you that the "clr r1" instruction >>> should be placed after the SREG has been pushed (obviously, as clr also >>> clears the SREG flags). >>> >>> But otherwise, I still think there's a bug :-) >>> >>> Regards, >>> Johannes >>> >>> _______________________________________________ >>> AVR-GCC-list mailing list >>> AVR-GCC-list@nongnu.org >>> http://lists.nongnu.org/mailman/listinfo/avr-gcc-list >>> >>> >> >> -- >> View this message in context: >> http://old.nabble.com/Compiler-error-creating-ISR-prologue--tp29420432p29435581.html >> Sent from the AVR - gcc mailing list archive at Nabble.com. >> >> >> _______________________________________________ >> AVR-GCC-list mailing list >> AVR-GCC-list@nongnu.org >> http://lists.nongnu.org/mailman/listinfo/avr-gcc-list > > > _______________________________________________ > AVR-GCC-list mailing list > AVR-GCC-list@nongnu.org > http://lists.nongnu.org/mailman/listinfo/avr-gcc-list > > -- View this message in context: http://old.nabble.com/Compiler-error-creating-ISR-prologue--tp29420432p29449211.html Sent from the AVR - gcc mailing list archive at Nabble.com. _______________________________________________ AVR-GCC-list mailing list AVR-GCC-list@nongnu.org http://lists.nongnu.org/mailman/listinfo/avr-gcc-list
