> > > The failing chip was yet another NS chip in plastic > > Can you see the type? I'd like to add to the page lists of all the > alternate > chip types DEC used in place of the Intersil chips specified in the > drawings. > > > I'll check all PROM chips on both board sets tomorrow.
> >> the 'F' etch rev has one less PROM chip than the 'E' etch rev, but I > >> suspect .. that it's not a micro-program chip, though > > My guess was correct; the missing chip is the one I called "Internal > interrupt acknowledge"; it was replaced with a 74154 4->16 demux. What about compatibility between different revisions? I.e. Is it possible to mix DataParh board and Control board from different revisions with different microcode? /Mattis > > Noel >
