Bill Nobel wrote: > Oh, your right…. I forgot about the 6309 trap vectors. But I see that in Nitros9 module 3 values are stored. $10ff @ $0000, $0008 @ $0002 & $20fe @ $0004 not sure as to the reason yet. > > Bill Nobel That would decode as $0000 sts >8 $0004 bra $4 which doesn't seem adequate as I don't see where any code is located at $4 on any direct page. Robert