Okay, I got the 11/34 up and running, and I loaded XXDP. It fails the trap test. The instructions state you should examine the stack pointer (777706) which shows it to be a value of 000470. This is supposed to tell you the address of the Program Counter, right? So I load address 470, and the value is 000330. What instruction is failing? Am I reading this right? Any help, as always, much appreciated. Thanks! Julian