Hej Wouter van Ooijen. Tack f=F6r ditt meddelande 12:43 2002-08-25 enligt= nedan: >IIRC (has been a long time) it takes a few AVR instructions to set or >celar a single output pin (also to decide on the value of a single pin?) The other way around! One instr on AVR. On PIC often a mirror register is to be used for i/o because of the dreaded= read-mod-write is reading from pins, possibly reading in a transient into= otput registers if you midify an output. Thus at least three instr is= needed on PIC making it much slower. Only safe way is to modufy in memory,= then copy that whole byte to output. The AVR read-mod-write from output _Latch_ ignoring actual pin level. /Morgan -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads