Problem solved. Added PAUSE 5 after each command sent in intialize subs setup: setpulse: setheader: and setactive: and works like a charm. Going to have a glass of wine. My guess is that in the BasicStamp code the interpreter takes a while but the PIC code needs no interpretation and therefore executes faster which was to fast for the FT639. By giving the chip time before the next instruction works. Thanks to all who tried to help. Much appreciated.