1 Jun
2009
1 Jun
'09
7:59 p.m.
IS the 4 slot backplane a DD11-BF or a DD11-CF? I don't think the M7891
will work in the -BF.
On Mon, Jun 1, 2009 at 9:56 PM, Paul Anderson <useddec at gmail.com> wrote:
I always used a M930 in the 11/40 and older machines,
and the M9300 in the
11/34 and newer machines. I have no way to check on the differences
now. now. Also, there may be a trick using MOS in an 11/40.
Paul
On Mon, Jun 1, 2009 at 3:23 AM, Josh Dersch <derschjo at mail.msu.edu>wrote:
Henk Gooijen wrote:
Date: Sun, 31 May 2009 20:39:26 -0700
Thanks -- installed the NPG jumper for slot 9, no change.
Here's a question: The M9300 Ian lent me has three jumpers, labeled as
follows:
W1 : "Remove jumper for beginning of non processor bus termination"
W2 : "Remove jumper for end of bus termination"
W3 : "Remove jumper for end of processor bus termination"
Currently, W1 is installed, W2 and W3 are removed. Is this correct?
I'm curious what is meant by "processor bus" vs. just "bus" in
this
context -- can someone fill me in?
Thanks,
Josh
From: derschjo at mail.msu.edu
To:
Subject: Further 11/40 unibus questions...
Hi all --
Still having trouble with my 11/40, though it's getting closer.
Currently the issue is:
Without a unibus terminator installed, the machine seems to function in
that I can use the front panel, toggle in and run short programs, etc.
With a unibus terminator installed, the front panel is _almost_
unresponsive -- I cannot examine or deposit memory or load addresses.
Toggling "Run" causes a brief flicker of activity (the "Run,"
"Proc,"
and "Bus" lights come on, the data lights flicker, and then they turn
off, and the "Console" light comes back on.).
Ian lent me his M9300 terminator, which caused no changes in behavior.
So at least I can (probably) rule out a faulty terminator.
I've verified that grant continuity cards (the tiny annoying ones) are
installed in slot D of all empty Unibus slots, and that the NPG jumper
is installed in all slots (since I currently have no DMA devices
installed).
Question: Should the NPG jumper _also_ be installed in the one SPC
Unibus slot on the processor backplane? (I have a console SLU installed
there currently.) This does not currently appear to be present.
Before I break out the logic analyzer this evening and start debugging
Unibus termination signals, I just wanted to make sure my current
configuration seems sane.
The boards are installed as follows:
Rear:
Slot 4 : Empty M9300
Slot 3 : Empty
Slot 2 : M7891
Slot 1 : Empty | M981
---
Slot 9 : M7856 | M981
Slots 1-8:
Front:
(As mentioned before, all "empty" unibus slots have a unibus grant card
+ NPG jumper installed, Slot 3 has the NPG jumper installed.)
Thanks once again,
Josh
The machine seems to do something (for a short while that is).
The only thing I can say is what I have encountered. I was triggered
when you wrote that you have the M7856 in slot 9 ... make sure that the
CA1-CB1 (NPG) pins are wired together on the backplane! The M7856 is
one of the modules that does not use NPG, but also does NOT connect the
two pins on the module! I have that written on my webpage www.pdp-11.nl
(peripheral - comm - interface modules - DL11-W).
I remember that I soldered a wire on the module to connect those two
pins,
as I did not want to mess with the backplane ... If you do so, make sure
that no flux and tin gets on the contact fingers!
- Henk.