<< The manual says the '54's PC defaults to 1F on power up. If I try to put something in that location like many of the MicroChip BBS examples I get an assembler warning. What's going on? Is this an assembler or simulator bug? Should I ignore the MPSIM warning? >> There is only room for 1 instruction at 1FFH, and that should be a GOTO to the start of your reset code (which should be at 100H or above, for security and to save valuable subroutine space). - Don