Thanks Sherlock, I got that ;-) 01 0101 0001 1100 = 0x151C 01 0100 1001 1100 = 0x149C It's the way 14 bits are spread over 2 bytes and how MPLAB extracts the 4-digit hex. It just so happens that the effect makes it look as though the op-code is in the wrong bank -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu