On Fri, 3 Jul 1998 13:05:43 -0700 WF AUTOMACAO writes: >James Grosbach wrote: >> >> What is the code not doing? Can you load the code into the MPLAB >simulator? Can >> you single step through it? >> >> I'm unsure how to assist without more information. >> >> Jim > > >Runs perfecly on Simulator! But "doesn't run" on PIC17C756! :( > >Something is very wrong! Here i have two samples in assembly! The >first runs perfectly and the >second not run! (nothing runs)! [samples deleted] > >The only diference is that there is a goto FORWARD! :( I doubt the GOTO instruction is a problem because the first version also contains one, and it works. There is a major difference in that the second (non-working) version extends beyond the first 8 program locations. Perhaps something is wrong with the address bus. Double-check that the addresses are wired correctly in and out of the address latch (not crossed over) and that they are not open or shorted (either to power, ground, or each other). Pay special attention to A3 as this is the one that becomes active with the second program but not the first. As a long shot, maybe the address latch chip is bad. Another test would be to add a few NOPs to the first program before the loop. If this makes it stop working, then it probably is a hardware address problem. > >And the Machine Code that the MPLABC-17 creates has as first >instruction: > >;-----------------------------------------------------------; >; Branch to startup code ; >;-----------------------------------------------------------; >0000 c0c2 GOTO 0xc2 ; goto _start section >_start_section CODE You'd have to look in location C2 to see what this is trying to do. I thought your examples were in assembler. Stick to assembler until you're sure the hardware is working properly. _____________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com Or call Juno at (800) 654-JUNO [654-5866]