Hi Legends, during corona times i “ported” Dave Cheney’s avr11 PDP11/40 emulator to a Teensy 4 MCU board, fixed already some bugs in it and added multiple rk drives and a partially working tm emulation. (space forward/reverse unimplemented) It runs V6 at about 1 Mips and is completely fine usable with multiple rk and tm drives. Playing around with V6 i noticed that Shoppa disk and tried to get ncc running, but after some debugging it looked like it is stuck in some loop which i think is due to possible bugs in the emulator code. So the question is, are there programs V6 runnable or rk bootable available which test the CPU functionality? I already hat a look at some xxdp disk, but the one i found (while they boot) seem to lack basic cpu tests. Best regards, Michael