One question though, if the other systems are working fine, why would you first suspect software? Component failure is a fact of life...no matter what the MTBF might be (usually a very educated estimate), there will always be those that are DOA or fail within a 24 - 48 hour time span...and some that wait 5 months. Granted, failures are not common, but if something is working for months and suddenly stops, my first inclination would not be software issues. But, that's just me. Tim -----Original Message----- From: pic microcontroller discussion list [mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of Dennis J. Murray Sent: Friday, November 15, 2002 9:17 AM To: PICLIST@MITVMA.MIT.EDU Subject: Re: [PIC]:failed data location? I've been programming a LOOOONG time in many different languages, mostly assembler. Believe me when I say I've made more programming mistakes and snafus than most of you've EVER thought possible!!! As a point of reference, my first FORTRAN program back in the 60's had well over 200 errrors, yet the program had less than 100 lines of code!! Beat that! Over the years, I've become very adept at tracking down programming errors - my carrer depended on it! In this case, my first & only thought was "I screwed up in the program somewhere", even though this particular unit had been running flawlessly since May (no, I never considered the assembler - I've NEVER had an assembler screw up my code!). I simulated the chip under MPLAB, isolating different sections & athrashing them heartily - no failure. I figured it must be a timing-related program failure, so I programmed a new chip and thrashed it every way I could think of - no failure. Thanks for your input, Scott. I just don't feel comfortable that I'm out of the woods by just replacing the chip. Dernnis ----- Original Message ----- From: "Scott Touchton" To: Sent: Thursday, November 14, 2002 8:26 PM Subject: Re: [PIC]:failed data location? > I will throw my 2 cents into the ring on the issue: > > I have seen RAM in the 16C54 that toggles on its own accord. Even > duplicated it with a combination of temp and supply voltage. The part was > "in specified operating range" all the time. No code bugs, just good ol' > marginal wafers. > > I was using in excess of 500K per year, and Microchip acknowledged the issue > with sincere apologies, but no remedy. > > > I find it highly likely this is what you are experiencing. Though human > error is usually the main culprit. > > -- > http://www.piclist.com hint: The list server can filter out subtopics > (like ads or off topics) for you. See http://www.piclist.com/#topics > > -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details. -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body