So, it appears that the KDJ11 (definitely the -A, and probably all of them) cannot execute code from the PARs - one gets a NXM trap. (Definitely the kernel I PARs, I haven't checked all 6 sets, but I can't see why they others would be any different.) Has anyone else run into this, so I can be sure I'm not confused? This is a mild pain, because it's nice to be able to put short 'scope loops in them, either to debug a memory card when you don't have any working memory plugged in, or when you don't want the bus 'contaminated' with instruction fetch cycles, etc. Noel