[rescue] FA: PDP11 Qbus cards CPU and Memory

Dave McGuire mcguire at neurotica.com
Sun Mar 24 20:19:04 CST 2002


On March 24, Greg A. Woods wrote:
> Just to be pedantic about the terminology, from the point of view of a
> pre-Micro PDP lover:
> 
> FYI:   generally PDP != Qbus
> 
> PDP-11's have Unibus.

  Umm, no.  SOME PDP11s have Unibus.  Some have Q-bus.

> LSI-11's aka MicroPDP-11's have Qbus (or Unibus) (with the one exception
> of the PDP-11/23-PLUS, which is a Qbus "micro" system, which is also at

  Umm, no.  An LSI-11 based system is a PDP11.  To my knowledge, there
are no PDP11 systems, regardless of bus, that say "LSI-11" on the
badge.  In short, PDP-11 is the name of the architecture and most (not
all) of the systems built around that architecture.  LSI-11 is an
implementation of the PDP-11 architecture, and a system built around
an LSI-11 processor is a PDP-11 computer.  While it is true that Q-bus
was once referred to as the "LSI-11 bus", that doesn't mean that a
Q-bus system isn't properly referred to as a PDP-11.

  Just to be pedantic about the terminology.

> the core of the so-called "Personal PDP-11", aka the "Professional 3xx"
> series)

  Umm, no.  The Pro series are based on the F11 and J11 processors,
a.k.a. LSI-11, but they have nothing akin to either Q-bus or Unibus.

      -Dave

-- 
Dave McGuire                    "Watch those lateral G's man,
St. Petersburg, FL               I've got sandwiches in my lap!" -Sridhar



More information about the rescue mailing list