PDP-11/05 returns to life

Henk> Search the net. There is a small program (estimate 7 words). It Henk> uses the RESET instruction (is that 000005?) ... not nice if Henk> you connect an RX01 or RX02 to the machine as on every RESET Henk> (INIT) the heads clunk! That's a bit ugly... A cleaner one is the RSTS null job. It relies on the fact that a number of PDP-11s -- including the 11/05 as far as I remember -- will display R0 in the lights during a WAIT instruction. RT11 won't do, that uses the status register so you need a machine that has it and that displays it. I forgot what RSX does. Not sure you could run that on an -05 anyway. Sufficiently old RT11s should work on that machine. So would RSTS V4A, if you can find an RK05 or RF11 or RP03 disk drive. :-) RSTS null job looks like this: ; THE SIMPLE NULL JOB 10$: MOV R2,R1 ;RELOAD THE WAIT COUNTER 20$: WAIT ;DISPLAY THE LIGHTS (R0) A WHILE SOB R1,20$ ;KEEP WAITING ROL R0 ;ELSE SHIFT PATTERN 1 PLACE LEFT BR 10$ ; AND AROUND AGAIN... You need a periodic interrupt, of course, to break out of the WAIT. paul