On February 17, Chuck McManis wrote:
> At 05:17 PM 2/17/00 -0500, McGuire wrote:
> >  Qbus is Qbus!
> 
> Not exactly, there is 18 bit Q-bus, 22 bit Q-bus, and Q/CD Q-bus (also 22
> bit) Quad wide cards may or may not work in a Q/CD slot, Dual wide cards
> will work in the AB slot of Q/CD or a Q slot if they are the same number of
> bits as the backplane (18/22). Its all written up in the MicroNOTES on the
> PDP-11 FAQ site.

  Well, aside from q18 vs. q22.  Q/CD vs. Q/Q is more of a physical
issue, unless you're dealing with a multi-board set like the RLV11,
which (if I recall correctly) actually uses the CD interconnect for
its own purposes.

  The notion that I had intended to convey was that the vast majority
of Qbus boards are compatible with both MicroVAX and Qbus PDP-11
machines.

           -Dave McGuire