Hello David . > Hi everybody, > I was away for a while, but I am now back. Don't matter, nobody knew me...:( Don't cry i remember you. ;) > I am back because I need your help. I have an ASM file that contains: > > sublw .3 > > and it is not working properly. When I am replacing it with addlw 0xFD, > everything is working! I though the assembler was translating a sublw > into the right addlw?! Is it the same opcode? David, look carefully in your PIC manual. I think you will be surprised because sublw K mean K-W result to W not W-K as you think ! But addlw -K works as you expect: W-K result to W . It's the Greate Microchip joke . ;))) WBR Dmitry.