It appears that my RK8E has a problem - it fails the diskless control test with
.R DHRKAE.DG SR= 0000 COMMAND REGISTER ERROR PC:1160 GD:0000 CM:0001 DHRKAE FAILED PC:6726 AC:0000 MQ:7777 FL:0000 WAITING Ok, maybe a bad bit in the command register so I'll check it out. But then it dawns on me - how do you work on this thing? It's three boards connected with "over the top" connectors - you can't use a module extender on it. Worse, the M7105 Major Registers board is the middle one of the stack! Is there some secret to working on this thing? Has anybody fixed one? Any suggestions? I hadn't thought about it before, but the KK8E CPU would have the same problem. Fingers crossed that one never dies... Bob