2016-03-17 17:27 GMT+01:00 Guy Sotomayor <g...@shiresoft.com>: > > > On Mar 17, 2016, at 6:01 AM, Mattis Lind <mattisl...@gmail.com> wrote: > > > >>> > > > > If one read notes in the PDP-11/04 printset it says: Do not insert a M930 > > or M9302 in a MUD slot. Only in the Unibus slots or you will have short > > circuit. On the other hand it does not say that the M9301 (or M9312) > cannot > > be installed in a unibus slot. It recommends that those boards go into > MUD > > slots. But electrically I cannot see that it shouldn't work. Especially > if > > you jumper W1 - W5. > > > > Hopefully this will clarify a few things: > “Unibus”: These are the AB connectors in the *last* position of a > backplane. > It allows for bridging between backplanes. The only “card” that can go > these > “slots” is a terminator (ie M930) or a terminator bootstrap (ie M9312). > > SPC: These are the CDEF connectors in any of the slots of a “unibus” > backplane. > Not all backplanes support SPC slots. > > MUD: These are the AB connectors in some newer backplanes (usually > associated with > the extra slots in a CPU backplane…11/34 and 11/04 CPUs have MUD slots). > MUD > stands for “Modified Unibus Device”. They are *not* compatible with > Unibus slots > as they have different voltages present than what are on the Unibus > slots. You *will* > “blow out” a board by plugging something designed for a Unibus slot into a > MUD > slot. > > Yes. That is pretty clear from pin assignment list that bad things WILL happen if you try to install a Unibus-slot-compatible device into a MUD slut. But the vice-versa? Installing a MUD-compatible device into a Unibus-slot?
> TTFN - Guy > > > /Mattis
