On Mar 30 2006, 19:09, Jay West wrote: and some something? I just had another thought. Standard traps for errors and software traps start at 4, and zero is reserved. Normal interrupt vectors for hardware devices use the area from 100 up to 400. 000000 is reserved, so if anything uses that as a vector, it's because you have some hardware fault. My guess would be something along the lines of a hardware device generating an interrupt, but apparently giving 000000 as a vector instead of the true value intended. Unlikely all three of your LTCs would do the same thing. Could be the CPU reading zeros due to a fault in the interrupt logic, as Tony suggested. -- Pete Peter Turnbull Network Manager University of York