? I have an 11/04 with an RK11-D.? I have a couple of RK05s, but I wanted to test the controller before I start working on the drives.? The PDP11 Diagnostic Handbook says that ZRKJ?? "checks only the drive-independent logic of the RK11 controller. no drive is needed..."? I assumed that meant it was a diskless test, but now I'm not sure that's true.? Can anyone confirm or deny this? Does anyone have a listing of ZRKJE0? ? My RK11-D has the BC11 drive cable plugged into the backplane, but the free end of the cable is just lying on the floor.? No drive is connected.? The test fails with ??? RK11 LOGIC TEST I ??? MAINDEC-11-DZRKJ-E ??? REGISTER NOT CLEARED ??? ? PC?? REGADD??? RECVD ??? 002560? 177402? 100000 ?177402 is the RKER register and bit 15 is DRE - "Drive Error". According to the manual this bit is set when the AC power to the drive is lost, which given that I don't have a drive at all, doesn't sound unreasonable.? Continuing ZRKJ?? also gives ??? REGISTER NOT CLEARED ??? ? PC?? REGADD??? RECVD ??? 002560? 177404? 140200 ??? RKCS ERROR ??? ? PC??? WROTE?? READ ??? 002636? 000002? 140202 177404 is the RKCS register and the first two bits are ERROR and HARD ERROR.? These are both set by the DRE bit in RKER and aren't really a surprise. ? I'm starting to wonder if this diagnostic really works w/o a drive attached, or if these errors are expected. Thanks, Bob