Bit of a pitfall this one. When debugging using the Keil ULINK sometime you want to reset your program using the handy reset button. (uVision 3 C166 V5.00)I am using the XC164 evalution board. However it does not seem to reset the CPU ILVL in PSW (interrupt proprity level in the processor status reg)to 0. I have a high speed ADC/PEC interrupt running at level 12. When I reset the evalution board the CPU level stays at 12! This means all my RTC interrupts and everything at ILVL level 12 and below don't run! Yuch! I found the solution was to manually set the PSW register ILVL part to 0 at the start of the main() function. Then everything works. This this a known bug?