Plessey's My First PDP-11

From: Wai-Sun Chia <waisun.chia_at_gmail.com>
Date: Fri Feb 18 21:50:38 2005

A 11/03 is QBUS.
In fact it is the first incarnation of QBUS (only 16bits physical,
therefore 32kW max), known during that time as LSI11.

And 9000 is right, you'd need more supply lines and signals than just
a signal +5V.
You'd need (from the H780 PSU manual):

+5V/18A _at_ 3%
+12V/3.5A _at_ 3%
BPOK H
BDCOK H
BEVNT L
BHALT L
SRUN L

This is assuming you use MOS memory and not core (MMV11-A). I don't
really recommend using MMV11-A as it'll eat up *FOUR* precious slots
on your backplane (at best, it'll take up only TWO slots if it's on
AD-D4).

On Fri, 18 Feb 2005 13:57:02 -0500, 9000 VAX <vax9000_at_gmail.com> wrote:
> On Fri, 18 Feb 2005 10:20:30 +0100, Tore S Bekkedal <toresbe_at_ifi.uio.no> wrote:
> > Yay, I have a PDP-11!! Yay! Yay!!
> >
> > It's a PDP-11/03, it's got a CPU, and RAM, and some interface cards.
> >
> > The backplane is a Plessey PM-F11/QU, shaped like this:
> >
> > F E D C B A
> > ___________________________________
> > 1 |_____|_____|_____|_____|_____|_____|
> > 2 |_____|_____|_____|_____|_____|_____|
> > 3 |_____|_____|_____|_____|_____|_____|
> > 4 |_____|_____|_____|_____|_____|_____|
> > 5 |_____|_____|_____|_____|_____|_____|
> > 6 |_____|_____|_____|_____|_____|_____|
> > 7 |_____|_____|_____|_____|_____|_____|
> > 8 | power |_____|_____|_____|_____|
> > 9 | regulator |_____|_____|_____|_____|
> >
> > I have connected an AT PSU to +5v and GND, though there is a +15v in. Is
> > this used for anything?
>
> I don't have a PDP11 but I have a VAX3900 which is QBUS based. From my
> knowledge the power supply should supply a bunch of signals. For
> example, DCOK, POK and INIT among others. There are +12v and -12v too.
> Yours might be a UNIBUS machine. But you can not just get a +5V and
> GND and expect it to work.
>
> vax, 9000
>
> >
> > I have tried plugging in a QBUS debugger I got on ABCD6, I have tried
> > plugging in the CPU (in AB9) with the debugger. Nothing. I can't get
> > anything to live.
> >
> > Where should I plug things?
> >
> > Does anything use the +15v?
> >
> > Any other voltages I need?
> >
> > Thanks for the help!
> >
> > --
> > Tore S Bekkedal <toresbe_at_ifi.uio.no>
> >
> >
>
Received on Fri Feb 18 2005 - 21:50:38 GMT