>I found both the XGDX and XGDY opcodes in my prom. >My prom is a 93 Z28 A4 prom. What does that instruction do? XGDX = Exchange D with X XGDY = Exchange D with Y -Mike ========================================== Mike Pitts Delray Beach, FL mpitts at emi.net http://www.emi.net/~mpitts/mike.htm ==========================================