Using the uVision2 debugger to simulate code for a Philips P89LPC920 with Watchdog enabled (via UCFG1): The Watchdog feed routine does not reload the Watchdog timer if I attempt to run the code without breakpoints. A Watchdog Reset occurs as a result. If I set a debug breakpoint at or just before the CALL to the Watchdog feed routine (thereby pausing the debugger at that point), the Watchdog reloads just fine when I continue running the program. Very weird. Is there some sort of race condition bug in the Simulator that anybody knows about??? (FYI, my main program loop takes about 30,000 machine cycles and the Watchdog is fed once per loop. I am using the onboard oscillator at 7.373MHz, driving the Watchdog from PCLK instead of the Watchdog oscillator, and using a Watchdog pre-scale factor of 128.) Thanks for any help. Steve