> On Jun 2, 2016, at 2:19 PM, Noel Chiappa <j...@mercury.lcs.mit.edu> wrote: > >> ... >> For whatever reason they managed to disable the unibus I/O > > I'm not sure you can (in hardware terms, that is - and clearly if there's no > way to do it in the hardware, the software cannot do so)... although it could > be broken.
I could imagine any number of signals that, if stuck, would make the bus
inoperative. Reset asserted, for example. Or AC LO or DC LO asserted,
possibly. Or NPG asserted.
paul
