Your Watchdog timer will change a lot over temperature. It could be that as you add new code, you are more critical on watchdog timer time. Steve --- On Sun, 27 Jul 1997 00:10:56 +0000 gary skinner wrote: We have been building a unit that uses commercial 16C54A in an application where it can get hot. We tested several of the first units and they worked well up to 200 degrees F and thought we were in good shape. Now we were testing another part of the project and are suddenly seeing failure at temperatures of about 140 deg F. The main failure is that the RAM sems to be lost, or it could be that the part somehow resets itself (and power up sequence resets the RAM) Anybody seen anything like this before? Or have any insights? Gary Skinner gskinner@csd.net Electronic Solutions, Inc. design of custom electronic controls -----------------End of Original Message----------------- ------------------------------------- E-mail: sdavidson@its.bldrdoc.gov Steven Davidson Dept. of Comm. NTIA-ITS.N1 325 Broadway Boulder, CO 80303 W 303-497-3411 FAX 6982 -------------------------------------