Need to be clearer. I cannot interfere with the customers' routines. Therefore, I can't 'break' in and print out register contents. So how do I say, "OK, Printf: print out what's at this address. " I tried passing R1 to PrintF. Unless I call is an unsigned integer, it doesn't help. And then it thinks it's a VARIABLE named R1, not the specific register. I tried @R1. Nothing there either. Is there a special symbol that says, "Look, this is an internal register. I want you to print the contents of it: e.g., #R1, *R1, %R1. Thanks, I need specifics.