Subject: I've been given a few more PDP-8 bits....

From: [email-masked] (PDP11 Hacker .....)
Date: Wed, 8 Jun 1994 20:26:00 GMT

Greetings...
I've just been given a few more odd bits for my PDP8 system, and I have a few
questions about them. Hopefully someone can help

a) A EAE board set for the 8/e (M8340 and M8341). I assume I just have to move
the 2 CPU cards in my CPU back 2 slots, stick these cards between the CPU and
the timing generator, and stick the connector blocks on top. I have the 8/e
maintenance manual and schematics, and that's what they seem to imply. I don't
need to do any mods to the CPU boards, do I?

b) A quad card, labeled M1705 on the handle, and DUAL 12 BIT OMNIBUS OUTPUT
INTERFACE on the solder side. Is this a 'User' Output port for e.g. lab control
- I can find nothing about it.

c) A 8K core board kit, tagged 'G111 faulty, fields 4,5'. Is there a common
fault that causes this?

d) 2 3rd-party boards. Green handles, quad cards, Labelled 'VG DS' and M246 or
V246. Contain DACs (including a Analog Devices DAC1136 :-)), and beleived to
come from a mass spectrometer. Any ideas?
(VG DS _may_ be Vacuum Generators Data System, or similar).

e) The real prize. Lots and lots of documentation. 
  Introduction to programming 
  PDP8 pocket reference
  RX01/RX02 reference card
  RL01/RL02 Technical manual
  PDP8/e maintenance manual (my second copy, but as I know someone
  who's rescuing a PDP8/e, he'll get this)
  Microfiche - PDP8/a and 8/e technical stuff (schematics, etc)
               VT50,52,55 manuals (lots of fun things...)
               LA180 and LA36 technical manuals
               Lots of diagnotics
  etc...

Quite a haul :-). I should be getting a PDP8/a with RL8 and drive(s) from there
soon...

-tony

Bristol University takes no responsibility for the views expressed in this
posting. They are the personal views of the user concerned.

---

From: [email-masked] (Charles Lasner)
Date: 9 Jun 1994 06:57:37 GMT

In article <[email-masked]>,
>need to do any mods to the CPU boards, do I?

Not exactly, but there are known restrictions about ECO levels of all of 
these cards together.  For example, I think the final rev EAE cards can't 
reliably work with the 8300 and 8310 cards unless they are also (near) final.

>- I can find nothing about it.

Some of the dismal older interfaces.  Some were output-only, some were 
input-only.  All shared the same brain-dead concept:  That the user 
circuitry would be wrapped on green blocks externally to the Omnibus, and 
these cards woujld plug into the Omnibus and buffer the signals to the 
user stuff using the same cables as the KA8E and KD8E (flip-chip on one 
end, Berg on the other.)  OF course, we eventually learned to put the 
interface and the user part on the same card!

>c) A 8K core board kit, tagged 'G111 faulty, fields 4,5'. Is there a common

Merely indicates the writer believes the G111 card is defective, and that 
it's for the 8K stack serving as fields 4 and 5 at the time.  Field 
select is determined by three jumpers in the lower right corner.  The 
low-order bit is ignored in 8K stacks, but is looked at on the 4K version 
(G104). (which is the same etch card).  The presence of a jumper=0, 
cut=1.  Factory and user jumpers are the same here (but not in all 
modules!) (Look at the M8650 for a good example!)  It could be thousands 
of things.

>(VG DS _may_ be Vacuum Generators Data System, or similar).

Could be anything.

>Quite a haul :-). I should be getting a PDP8/a with RL8 and drive(s) from there

Lotsa good stuff in that list :-).

>posting. They are the personal views of the user concerned.

cjl

---

From: [email-masked] (PDP11 Hacker .....)
Date: Thu, 9 Jun 1994 10:56:00 GMT

In article <[email-masked]>, [email-masked] (Charles Lasner) writes...

[EAE revision levels]

>reliably work with the 8300 and 8310 cards unless they are also (near) final.

The cards are dated OCT 1974, and have the labels M8340E on the solder side. I
can find no other revision letters on them. Are those cards likely to work with
my 8/e, and if not, what should I check first? I have the schematics to
everything (including one rev. of the EAE), and a logic analyser.

[Output card]
>circuitry would be wrapped on green blocks externally to the Omnibus, and 

Is that the only thing that's brain-dead about them? If so, and assuming it's a
latched 12-bit TTL output, it seems quite sensible.  I can use berg-berg cables
to hook it up to my own device.

>interface and the user part on the same card!

I got 3 of those cable thrown in with the stuff....

[Faulty G111]
>it's for the 8K stack serving as fields 4 and 5 at the time.  Field 

Aha... I'd got confused as to the size of a field, and though it might mean
that an address driver to the XY plane had failed. Still, I'll have a go at
sorting it out.

>modules!) (Look at the M8650 for a good example!)  It could be thousands 

OK. I have schematics and the maintenance book.  Can't be that bad. I fixed the
Core Memory in my P850 with no schematics at all...

>Lotsa good stuff in that list :-).

True... I should have a PDP8 with some periphrals soon... so then I can run
some real software...

-tony