Hello People, I've found a piece of code that looks very strange ... I think I know what it does, but want a second opinion. By the way, I suspect that this piece of code is the result of an 'higher' programming language (Yes, I'm debugging someone else's code). The controller it's ment for is the 17C42. Here's it : ------------------------------------------------ cblock SrcRegL SrcRegH TrgRegL TrgRegH endc clrf TrgRegL clrf TrgRegH movfp WREG,SrcRegH addwf TrgRegL btfsc ALUSTA,C incf TrgRegH movfp FSR0,TrgRegL movpf FSR0,TrgRegH clrf TrgRegL movfp WREG,SrcRegL addwf TrgRegL btfsc ALUSTA,C incf TrgRegH ------------------------------------------------ Greetz, Rudy Wieser