24 May
2016
24 May
'16
4:49 a.m.
From: Bill Degnan
I removed the core backplanes and returned the DD11-C
to the orig
config next to the CPU. I re-inserted cards as-was. I am not getting
comms from the M7856.
Ugh. Not good. Does it respond on the UNIBUS? (I.e. if you try to read
the registers from the front panel?)
I may have shorted the card.
If you somehow plugged it into one of the core backplanes, good chance, alas.
They have either -15V or +20V (I think the latter, for the MM11-U) running
around on various pins.
(Oh, BTW, you probably already know this, but just in case not: those
backplanes take specific boards in specific slots; check the manuals/prints
for the correct slots.)
Do you have a spare M7856 you can swap in to make sure the machine is
otherwise functional? If not, let me know, I have a bunch of spare M7800's,
I can send you one (known, tested good).
Noel
24 May
24 May
5:50 a.m.
There have been a lot of parallel discussions on my PDP 11/40, I am
consolidating them all here:
I now have 5 backplanes installed. Here they are, described in order. I
walked through this will Paul Anderson last night (thanks Paul!) to verify
everything was in the right place and in the right order, in the right
power, etc. The +5V is a little weak but I can tweak it, etc.
1. CPU backplane. This is the same backplane I have had running/working
for 10 years. There is no M2737 or M787 installed, just a stock CPU card
set. No changes have been made.
2. core backplane #1 32k x 16 - 18 Memory backplane 500344C. This
backplane has one set of core cards installed in the order they came from
another system. These are electrically ok, but not tested/known to pass
memory tests. The M8293 is set to 0000
9/11: M981 (1-2)
11: M8293 (3-6)
12: M7259 (1-2)
13: G114
14: H217C
15: G235
The 2nd half of the 1st core backplane is empty.
3. The 2nd core backplane is empty. There are M920's on either end to
connect them
4. The next backplane is a DD11B. This is empty other than grant cards in
each slot D.
An M9202 connects the DD11B to the next backplane
5. The final (5th) backplane is a DD11C
In the first slot (closest to the front) GC in slot 4.
In the 2nd there is a M7261 RT11 drive controller. This slot requires a
NPG G7273 installed if not in use, the M7761 requires this kind of slot.
It's not hooked up to anything (RL02).
In the 3rd slot is an M9312 with console prom and RL01/02 boot prom. Not a
terminator
In the 4th slot is a M930 on top with a G7273 in 3/4. The G7273 is
required because previously the NPG was removed from wirewrap per
requirements for installation of M7762 RL11. This was done before I
learned I could have just used slot 2nd, which comes from the factory that
way. Bummer but that's what I've got.
WHEN I POWER UP - I have full console access, everything "works" and now I
have to start diagnosing the core to find at least 16K that I can play
with. With the current set of core cards I can toggle in data into
addresses, but it's not perfect (line 20000 sticks). Once I am operating
with a working set of core I will then turn my attention to the RT11 card,
and find a working serial card so I can use a terminal and PDP11GUI, etc.
I have spare core cards to draw upon, I had pulled a good set for my 11/05
I could always use those if need be.
Thanks everyone for your help and suggestions.
Bill
6:32 a.m.
2016-05-24 14:50 GMT+02:00 william degnan <billdegnan at gmail.com>:
There have been a lot of parallel discussions on my
PDP 11/40, I am
consolidating them all here:
I now have 5 backplanes installed. Here they are, described in order. I
walked through this will Paul Anderson last night (thanks Paul!) to verify
everything was in the right place and in the right order, in the right
power, etc. The +5V is a little weak but I can tweak it, etc.
1. CPU backplane. This is the same backplane I have had running/working
for 10 years. There is no M2737 or M787 installed, just a stock CPU card
set. No changes have been made.
2. core backplane #1 32k x 16 - 18 Memory backplane 500344C. This
backplane has one set of core cards installed in the order they came from
another system. These are electrically ok, but not tested/known to pass
memory tests. The M8293 is set to 0000
9/11: M981 (1-2)
11: M8293 (3-6)
12: M7259 (1-2)
13: G114
14: H217C
15: G235
The 2nd half of the 1st core backplane is empty.
3. The 2nd core backplane is empty. There are M920's on either end to
connect them
4. The next backplane is a DD11B. This is empty other than grant cards in
each slot D.
An M9202 connects the DD11B to the next backplane
5. The final (5th) backplane is a DD11C
In the first slot (closest to the front) GC in slot 4.
In the 2nd there is a M7261 RT11 drive controller. This slot requires a
NPG G7273 installed if not in use, the M7761 requires this kind of slot.
It's not hooked up to anything (RL02).
In the 3rd slot is an M9312 with console prom and RL01/02 boot prom. Not a
terminator
In the 4th slot is a M930 on top with a G7273 in 3/4. The G7273 is
required because previously the NPG was removed from wirewrap per
requirements for installation of M7762 RL11. This was done before I
learned I could have just used slot 2nd, which comes from the factory that
way. Bummer but that's what I've got.
WHEN I POWER UP - I have full console access, everything "works" and now I
have to start diagnosing the core to find at least 16K that I can play
with. With the current set of core cards I can toggle in data into
addresses, but it's not perfect (line 20000 sticks). Once I am operating
with a working set of core I will then turn my attention to the RT11 card,
and find a working serial card so I can use a terminal and PDP11GUI, etc.
I have spare core cards to draw upon, I had pulled a good set for my 11/05
I could always use those if need be.
Thanks everyone for your help and suggestions.
Bill
But the M9312 has bus terminating resistors (unless you actually desoldered
those!). Then you have three terminators in your system! One in the M891 at
the CPU, one in the M9312 in slot 3 of last DD11, and then a M930 in slot 4
of DD11.
If you want the M9312 you should put it with W1-W5 installed in the slot 4
where you have the M930. You should not have both a M930 and M9312 (when
you have the M891).
/Mattis
6:37 a.m.
But the M9312 has bus terminating resistors (unless you actually desoldered
those!). Then you have three terminators in your system! One in the M891 at
the CPU, one in the M9312 in slot 3 of last DD11, and then a M930 in slot 4
of DD11.
If you want the M9312 you should put it with W1-W5 installed in the slot 4
where you have the M930. You should not have both a M930 and M9312 (when
you have the M891).
/Mattis
After I sent the email to this group, I checked the M9312 and found it was
terminated. I was told it was not, I should have checked for myself but I
grew suspicious that it should be by default. Now, the M9312 is in the
last slot, and I removed the M930. There is nothing except a grant card in
the 3rd slot.
I fixed the core problem I described in my email. I also am able to store
into core and run "chase the lights", I have generally speaking a working
16K system.
Thanks again.
Next - Get a serial card running and resume efforts to boot RT11 from an
RL02 drive.
Bill
--
@ BillDeg:
Web: vintagecomputer.net
Twitter: @billdeg <https://twitter.com/billdeg>
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7:12 a.m.
2016-05-24 15:37 GMT+02:00 william degnan <billdegnan at gmail.com>:
Good. But what is the status of W1-W5 of the M9312? Installed or not?
The usage of AU1 and AV1 differs in Unibus slot versus a Modified Unibus
(MUD) slot. The MUD slot uses those two pins for +20V Core power. You don't
want to have the jumpers installed when you put the M9312 in a MUD slot (if
there is +20V in your system). Then smoke will escape I guess.
But If you use it as a terminator in a unibus slot then then you want them
to terminate the BGx and NPG lines thus you need to install the jumpers.
Now I don't really know if your backplane has MUD wiring or not. I think
MUD wiring is a later DEC invention when there were selfcontained unibus
core memory modules. Not entire backplanes.
But be carful with the jumpers. On the M9302 for example there are big
print that tell you something will go bad if you install it in a MUD slot...
But the M9312 has bus terminating resistors (unless you actually
desoldered
those!). Then you have three terminators in your
system! One in the M891
at
the CPU, one in the M9312 in slot 3 of last DD11,
and then a M930 in
slot 4
of DD11.
If you want the M9312 you should put it with W1-W5 installed in the slot
4
where you have the M930. You should not have both
a M930 and M9312 (when
you have the M891).
/Mattis
After I sent the email to this group, I checked the M9312 and found it was
terminated. I was told it was not, I should have checked for myself but I
grew suspicious that it should be by default. Now, the M9312 is in the
last slot, and I removed the M930. There is nothing except a grant card in
the 3rd slot.
I fixed the core problem I described in my email. I also am able to store
into core and run "chase the lights", I have generally speaking a working
16K system.
Sounds really good!
Thanks again.
Next - Get a serial card running and resume efforts to boot RT11 from an
RL02 drive.
What never was clear to me was if you actually could access the serial card
or not from the console. I.e. did it respond when addressing it? If it did
respond I would check that there were correct power supplied to the 1488
driver.
/Mattis
Bill
--
@ BillDeg:
Web: vintagecomputer.net
Twitter: @billdeg <https://twitter.com/billdeg>
Youtube: @billdeg <https://www.youtube.com/user/billdeg>
Unauthorized Bio <http://www.vintagecomputer.net/readme.cfm>
8:03 a.m.
What never was clear to me was if you actually could access the serial card
or not from the console. I.e. did it respond when addressing it? If it did
respond I would check that there were correct power supplied to the 1488
driver.
/Mattis
The M9312 does yes have the terminators installed.
I have not been able to activate the M9312 with the DD11C backplane
"behind" the newly-installed core and DD11B backplanes. I don't know if I
fried it somehow recently. It was working before. The M9312 is installed
on the 4th slot in the DD11C with a NPG card below it. It is also possible
that instead I am not communicating with the cards in the back of the bus.
Typically I toggle and run from address 165144 from the front panel, then
use the console program from a terminal to go from there. Since my recent
shenanigans with the backplanes the console program does not appear to load
nor run.
When I load the address 165144 I see the correct address on the front
panel. RUN BUS PROC CONSOLE are all lit. When I enable and start the
system the address lights go out except 020 (2nd to last light). The RUN
BUS PROC CONSOLE stay lit.
When I examine
165144 177570
165146 177570
165150 177570
165152 177570
etc
I don't know the status of my M7856 card. There are things I can try but
first I believe I should test to see if I am "pinging" to the DD11C at
all. I also need to check power output levels and adjust.
I am thinking also test the MOS RAM from the DD11C by itself to see what
that tells me. I know to address the RAM somewhere other than the 16K
space from 000.
Bill
8:09 a.m.
The DD11C was modified a while back. I also need to probe the system to
confirm what slots need a NPG grant card, make sure everything is
documented. I *think* it's slot 4 and 2 that need them, but I should
verify this vs. the manual default.
8:36 a.m.
On Tue, May 24, 2016 at 11:17 AM, js at cimmeri.com <js at cimmeri.com> wrote:
On 5/24/2016 8:37 AM, william degnan wrote:
I guessed that the G114 was bad based on a hunch.
I had a spare.
b
--
@ BillDeg:
Web: vintagecomputer.net
Twitter: @billdeg <https://twitter.com/billdeg>
Youtube: @billdeg <https://www.youtube.com/user/billdeg>
Unauthorized Bio <http://www.vintagecomputer.net/readme.cfm>
... I fixed the core problem I described in my
email. ... Bill
B, what was the issue with the core, that you fixed it so fast?
- J.
3134
days inactive
3134
days old
8 comments
4 participants
participants (4)
-
billdegnan＠gmail.com -
jnc＠mercury.lcs.mit.edu -
js＠cimmeri.com -
mattislind＠gmail.com