Re: DEC bus transceivers

[Christian Corti]

On Tue, 25 Oct 2016, Guy Sotomayor Jr wrote:

OK, re-reading the first part of section 5.2.5, it?s pretty clear that the 
Unibus is 120-ohm:
A bus terminator is defined as a Unibus element or part of an element containing
a resistive network which connects to the end of a Unibus segment and matches
the 120-ohm characteristic impedance of the Unibus transmission path.


Or to cite another source: PDP11 Bus Handbook page 76 says
"A bus segment consists of a terminator, a 120-ohm transmission path 
(cable) with options having drivers and receivers, and another terminator 
(in that order)."


Christian

Re: DEC bus transceivers

[allison]

On 10/25/2016 04:24 PM, Guy Sotomayor Jr wrote:
>> On Oct 25, 2016, at 12:40 PM, allison  wrote:
>>> Also, I think in a previous email you mentioned that the UNIBUS is 240ohm.  
>>> It’s not.
>>> It’s 120ohm.
>> My book says no. Qbus is for sure 120.
>>
> Section 5.2.5 of the PDP-11 UNIBUS spec:
> A Unibus segment must always have a Unibus terminator at each end of its
> 120-ohm transmission path.
>
> So, I don’t know how you get a value of anything other than 120-ohms given 
> that
> statement.
Its not.  It may be close but  What your reading is the terminator
value (R1+R2)/R1*R2=120.
thats a terminator and its also limited in the range of values because
the DEC part can only
sink so much and also the terminator has to source current as the driver
can't.   Likely
the line impedance can be in the range of 120 ohms, maybe.  I"ll have to
drag out a
Qbus back-plane and measure it.  I don't have any Unibus.

As far as the chips themselves.  They do NOT match the line impedance as
they have
a active low value in the 10 ohm range and when in the high state they
are just an open
or somewhere in the effectively infinite range certainly more than
several thousand ohms.
That's a terrible mismatch for transmission lines, aka bus.  The
combination of wacky
source impedances and near open load impedance (input current varies
with source
voltage Vih and Vil) plus parallel capacitance from package and traces
on board means
that as a load its a horrid mismatch as well. With all that reflections
(ringing) are to be
expected and the only thing that can help that is the terminator even
then only to a point.
In short most TTL are no better and those designed to do bus interface
are about the same.
Also CMOS would be far worse as a receiver and some CMOS makes a better
transmitter
but they are incompatible with Unibus/Qbus as they actively source current.

The only common tech that does line matching especially from that era is
ECL, or current
mode logic.

This is why faster buses  are so difficult to make right.  And if
possible they are to be
avoided or made small as possible.  Been there and done that,, mixed
signal design
for the last 40 years.


Allison


> TTFN - Guy
>
>

Re: DEC bus transceivers

[Noel Chiappa]

> From: Guy Sotomayor

> Secondary chip marke[t] (only reputable vendors). 

I'm a little more willing than Guy to troll in disreputable waters (I bought
1K DS8641's from a source in Hong Kong), so I have this:

  http://ana-3.lcs.mit.edu/~jnc/tech/QSIC/TestCardF.jpg

which has a bunch of special circuits on it to test chips to make sure they
meet specs; e.g. the large potentiometer is so I can vary the input voltage
to see where it switches from 0 to 1, etc.


> From: Paul Koning

> it would be odd to have one; I can't think of anyone who would expect a
> PDP11 to work with part of its devices powered down. For one thing, if
> the box with the terminator loses power

Forget the terminator - as Jon Elson also points out (his email appeared
while I was creating this one), any device which uses interrupts, if
un-powered, won't pass grants.


> From: allison

> Bottom line is someday there will be no DEC parts and what then? I
> reserve DEC parts for repairing defunct boards for new and unique build
> it would be a waste of scarce material. 

For actual DEC interface IC's like DC003's, sure. Those are hyper-rare.

But DS8641's are available in the 10's of thousands, there's no earthly way
we could use them all on repairs. Yes, when they run out, we'll have a
problem - but I plan to cross than bridge _if_ and when we get to it.

Noel

Re: DEC bus transceivers

[allison]

On 10/26/16 7:38 AM, Noel Chiappa wrote:

 > From: Guy Sotomayor

 > Secondary chip marke[t] (only reputable vendors).

I'm a little more willing than Guy to troll in disreputable waters (I bought
1K DS8641's from a source in Hong Kong), so I have this:

   http://ana-3.lcs.mit.edu/~jnc/tech/QSIC/TestCardF.jpg

which has a bunch of special circuits on it to test chips to make sure they
meet specs; e.g. the large potentiometer is so I can vary the input voltage
to see where it switches from 0 to 1, etc.


 > From: Paul Koning

 > it would be odd to have one; I can't think of anyone who would expect a
 > PDP11 to work with part of its devices powered down. For one thing, if
 > the box with the terminator loses power

Forget the terminator - as Jon Elson also points out (his email appeared
while I was creating this one), any device which uses interrupts, if
un-powered, won't pass grants.


 > From: allison

 > Bottom line is someday there will be no DEC parts and what then? I
 > reserve DEC parts for repairing defunct boards for new and unique build
 > it would be a waste of scarce material.

For actual DEC interface IC's like DC003's, sure. Those are hyper-rare.

I have those too.  You need them to maintain DEC cards.
Then again I have a few of the chipkit proto cards too.

But DS8641's are available in the 10's of thousands, there's no earthly way
we could use them all on repairs. Yes, when they run out, we'll have a
problem - but I plan to cross than bridge _if_ and when we get to it.
What vendor and price???  They have been scarce save though resellers 
that have NOS parts from
old stocks and they are not cheap and unpredictable quantities.  TI the 
only source when they consumed
National Semi is the listed source has it as obsolete out of 
production.  The second source Signetics
went away decades ago before Phillips consumed them.  Then I could buy 
them they are about

.86 dollar US, but that was in the early 80s.

Every time I see something written suggesting the the 86xx parts are 
magical I go back to the
databooks (National and Signetics from the 70s and the current TI) and 
find nothing that

special or unique.

If you have them great, when you run out I'm not giving up the supply I 
have from DEC.



Allison

Noel

Re: DEC bus transceivers

[Noel Chiappa]

> From: allison

> What vendor

I don't recall, would have to look it up; I turned Guy onto them, and he
bought out everything they in stock.

> They have been scarce save though resellers that have NOS parts from
> old stocks and they are not cheap and unpredictable quantities.

Yeah, that vendor said they could get more (apparently from others who still
had stocks), but they'd be slightly more expensive. Apparently these people
all interact, and deal stuff around.

So that figure I was given of 30K in stock is probably not from that one
vendor, but across all of them. But since nobody is using these chips in a
product (that I know of), I suspect the number is likely to go down only
slowly.

> Then I could buy them they are about .86 dollar US, but that was in the
> early 80s.

The ones Guy and I recently bought were about $1 each (I don't recall the
exact amount, would have to check). So not cheap, but not ridiculous.

Noel

Re: DEC bus transceivers

[Paul Koning]

> On Oct 26, 2016, at 9:07 AM, Noel Chiappa  wrote:
> 
>> ...
> 
> So that figure I was given of 30K in stock is probably not from that one
> vendor, but across all of them. But since nobody is using these chips in a
> product (that I know of), I suspect the number is likely to go down only
> slowly.

The trouble with chip resellers is that it's hard to know which ones are legit, 
and which ones are in the fake chip business.  There have been some articles in 
the trade press about chips being sold with false labels, typically with some 
sort of chip inside but not anything like what the number on the outside 
indicated.  You might get a memory chip instead of a microprocessor, for 
example, or a 7400 instead of something more valuable.

paul

Re: DEC bus transceivers

[Noel Chiappa]

> From: Paul Koning

> The trouble with chip resellers is that it's hard to know which ones are
> legit, and which ones are in the fake chip business.

I suspect that the network of major resellers would tend to keep out the
riff-raff. (They don't need the aggro of dealing with the consequences.)

> a 7400 instead of something more valuable.

Which is why it's good that the DS8641's are going for little more than a
buck; at that price point, there's only minimal benefit from faking them.


Anyway, for any I get, random samples go straight into my tester board!
"Trust, but verify!" :-)

Noel

Re: DEC bus transceivers

[Philipp Hachtmann]

Hi,

On 10/25/2016 10:49 PM, Guy Sotomayor Jr wrote:

Secondary chip marked (only reputable vendors).  I currently have ~2500 8641
and several 100’s of the other variants.  Assuming 100% good parts, I have
enough stock to build at least 100 unibus boards (total) of various types that I
have planned.

And to forestall any questions on the topic, no I will not be selling any of the
chips individually.  They are there to allow me to build/sell the various Unibus
boards.


Very enlightening.
You're hoarding interface ICs with commercial second thoughts while 
deeming any usable alternative as not working crap. Sounds quite coherent!


BTW Why isn't there a separate list "ccbusinterfacechip" where those 
recurring 8881 discussions can be separated from the more interesting stuff?


I just can't imagine that it should be a real problem to build working 
Unibus equipment without the old chips.


The Unibus design is from 1 9 7 0 (or around that). Just read that 
sentence loud.


Kind regards

Philipp

Re: DEC bus transceivers

[Guy Sotomayor Jr]

> On Oct 26, 2016, at 7:02 AM, Philipp Hachtmann  wrote:
> 
> Hi,
> 
> On 10/25/2016 10:49 PM, Guy Sotomayor Jr wrote:
>> Secondary chip marked (only reputable vendors).  I currently have ~2500 8641
>> and several 100’s of the other variants.  Assuming 100% good parts, I have
>> enough stock to build at least 100 unibus boards (total) of various types 
>> that I
>> have planned.
>> 
>> And to forestall any questions on the topic, no I will not be selling any of 
>> the
>> chips individually.  They are there to allow me to build/sell the various 
>> Unibus
>> boards.
> 
> Very enlightening.
> You're hoarding interface ICs with commercial second thoughts while deeming 
> any usable alternative as not working crap. Sounds quite coherent!
> 

I’m saying I won’t use another alternative until that alternative has been 
proven to work in large scale systems.  I have enough troubles with getting my 
Unibus systems to work with BC11A cables (which have always been marginal even 
“back in the day”).  Too much of the discussions on Unibus interfacing has been 
“hey, I’ll use (fill in the blank) chips I have, it should work”.  I’ll shut up 
about it when someone does an actual engineered design.

> BTW Why isn't there a separate list "ccbusinterfacechip" where those 
> recurring 8881 discussions can be separated from the more interesting stuff?
> 
> I just can't imagine that it should be a real problem to build working Unibus 
> equipment without the old chips.

Because AFAIK, no one has done the actual engineering to come up with reliable 
replacements.  As I said, until that’s done I’ll stick with the old chips.

BTW, with modern designs (i.e. 3.3v I/Os) using the old interface chips is a 
pain.  First they’re 5v I/Os and 2nd they don’t do tri-state.  So you need a 
2nd set of interface chips that are 5v tolerant and convert the I/Os (at least 
the ones you care about to tri-state.  I spend more board area and parts count 
on interfacing to the Unibus than actually implementing what I want.  For 
example, the MEM11A board has 3 active parts that are actually doing the work, 
all of the rest of the board and parts (over a dozen) are for interfacing to 
the unibus.

TTFN - Guy

Re: DEC bus transceivers

[Christian Gauger-Cosgrove]

On 26 October 2016 at 10:02, Philipp Hachtmann  wrote:
> BTW Why isn't there a separate list "ccbusinterfacechip" where those
> recurring 8881 discussions can be separated from the more interesting stuff?
>
The discussion is enlightening. It would be nice, however, to
summarize the various conclusions into, say, a Wiki page (isn't there
a classic computers Wiki out there?). That way the discussion needn't
be rehashed ever so often like it always does.


Cheers,
Christian
-- 
Christian M. Gauger-Cosgrove
STCKON08DS0
Contact information available upon request.

Re: DEC bus transceivers

[Jerry Weiss]

> On Oct 26, 2016, at 9:18 AM, Christian Gauger-Cosgrove 
>  wrote:
> 
> On 26 October 2016 at 10:02, Philipp Hachtmann  wrote:
>> BTW Why isn't there a separate list "ccbusinterfacechip" where those
>> recurring 8881 discussions can be separated from the more interesting stuff?
>> 
> The discussion is enlightening. It would be nice, however, to
> summarize the various conclusions into, say, a Wiki page (isn't there
> a classic computers Wiki out there?). That way the discussion needn't
> be rehashed ever so often like it always does.
> 


See www.brouhaha.com/~eric/retrocomputing/dec/interfacing/chips.html 
 for 
starters


Jerry

Re: Reasonable price for a complete SOL-20 system?

[Mark J. Blair]

> On Oct 25, 2016, at 12:59, Terry Stewart  wrote:
> Lovely.  I'm sure the sloping wood-(veener) sided case design of the Dick
> Smith System 80 was inspired by the SOL.
> 
> http://www.classic-computers.org.nz/system-80/hardware_s80-mk1-front-800.jpg

Oh yes, the styling is clearly very similar. I like the built-in tape drive. Do 
you think that was likely inspired by the Commodore Pet?

-- 
Mark J. Blair, NF6X 
http://www.nf6x.net/

Re: DEC bus transceivers

[Noel Chiappa]

> From: Philipp Hachtmann

> Very enlightening.
> You're hoarding interface ICs with commercial second thoughts

If you think either Guy, or Dave and I, expect to make much money selling the
QBUS/UNIBUS boards we are working on, you are seriously confused. None of us
are in this as a money-making exercise; there are easier ways to make a lot
more money.

And as to the hoarding, if you'd like to buy up a couple of thousand yourself,
from that miniscule stockpile of 30K units that Guy and I have left out there
for you all, please let me know, and I'll expidite over a name, phone number,
and email for you to contact.

Noel

Re: DEC bus transceivers

[Pete Lancashire]

Guy S.


Thanks saved me the time to say exactly what you said. For all those that
thing designing a driver is a simple thing to do, make your self a
simulated Unibus that is 50 feet long, add around 30 'stubs' load it down
to the max and show me your 'easy to build' drivers signal quality.

On Mon, Oct 24, 2016 at 11:13 AM, Guy Sotomayor Jr 
wrote:

>
> > On Oct 24, 2016, at 10:37 AM, allison  wrote:
> >
> > On 10/23/16 2:59 PM, Al Kossow wrote:
> >>
> >> On 10/23/16 11:50 AM, shad wrote:
> >>
> >>> The problem is that there aren't open drain bus transceivers, but the
> >>> problem could be solved simply using input-only and output-only
> components,
> >>> connecting two in parallel but opposite direction on bidirectional
> pins.
> >>>
> >> The reason for using the old parts is the logic thresholds are unique to
> >> the Unibus to handle worst-case bus loading and the termination voltage
> they
> >> used.
> >>
> >>
> > The voltages are based on TTL levels.  What are the unique voltages?
> >
> > The key was limited leakage current and input current to not load the
> bus by inserting or removing
> > current from a node (there is a specified maximum in per node and total
> nodes).  That cover input
> > to card devices and bus driver leakage.
> >
> > Logic low voltage is typical of TTL and the driver device has to sink
> that current and meet that value.
> > Logic High was set by the terminator devices at 3.36V but the threshold
> is lower based on the bus
> > receivers.
> >
> > By late 1970 it was an easy spec to meet,  When first used (pdp8e) it
> was new and the ICs
> > were not so great with leakage current and output device saturation
> current.
> >
> > Every time this comes up the world is supposed to stop if not met. The
> LSI-11 bus (qbus)
> > was actually harder as it was 120 ohm terminated and HeathKit did it
> with common TTL
> > and the CPU was DEC standard LSI-11 and it worked out to 18 slot
> backplanes.
> >
> >
>
> The biggest concern is when interfacing to UNIBUS.  In the PDP-11 UNIBUS
> Design Description
> document on Bitsavers, page 4-1 indicates what the Unibus interface chips
> are and what are *not*
> recommended (8640, 8641 and 8881 are the only ones recommended).
>
> There are a number of rules that must be adhered to when building out a
> Unibus system.  These
> include:
> Maximum cable length must be < 50’
> Maximum DC loading < 20
> Maximum lumped loading < 20
> There are rules where cable lengths must be *increased* to avoid
> reflections.
>
> A single Unibus can be divided into multiple segments.  Each segment must
> adhere to the above
> rules, so you can see that a Unibus can be quite large.
>
> For example, my PDP-11/40 resides in 2 BA11-F boxes (23” tall) and are
> fully populated with
> Unibus backplanes (5 9 slot backplanes each) with a BA11-15 (15’ cable)
> connecting the two.
>
> My point here is that the Unibus has a very different electrical
> environment than Q-bus or Omnibus
> and what may work for them will probably have troubles on a Unibus.
>
> TTFN - Guy
>
>
>

Re: DEC bus transceivers

[allison]

On 10/26/16 7:38 AM, Noel Chiappa wrote:
  


But DS8641's are available in the 10's of thousands, there's no earthly way
we could use them all on repairs. Yes, when they run out, we'll have a
problem - but I plan to cross than bridge _if_ and when we get to it.

Noel

Actually since about 1987 I've used about 1200 pieces of the 8641 alone 
repairing boards
at the commercial level.  Up till recently I had a side business keeping 
commercial in use
pdp-8 and pdp11 system in NC machines.  Subs are not possible in that 
case as its all
about pin out and form factor.  Same for unique no-DEC boards in that 
service.
There is no choice for them, it has to fit the same hole.  And most of 
the 11s were Qbus

as the Unibus machines even minimal sized ones were generally large.

No they are scarce, any parts are NOS(new but old stock) of an out of 
manufacture part.
If you going to build a board or three maybe even 20 its not a big deal 
but its not
a reliable source of predictable quality.If you get to the bridge 
your talking redesign
in reality or an expensive buy from unreliable source then testing them 
in bulk.


Allison

Re: DEC bus transceivers

[Mouse]

> The trouble with chip resellers is that it's hard to know which ones are leg$

And then there are the periodic mentions of supposed chip vendors who
ask you what package and what pin count when you ask them for a part
that has never existed except in one version.

/~\ The ASCII Mouse
\ / Ribbon Campaign
 X  Against HTMLmo...@rodents-montreal.org
/ \ Email!   7D C8 61 52 5D E7 2D 39  4E F1 31 3E E8 B3 27 4B

Re: DEC bus transceivers

[Noel Chiappa]

Re: DEC bus transceivers
> From: allison

> Actually since about 1987 I've used about 1200 pieces of the 8641 alone
> repairing boards at the commercial level.

Well, that's over almost 30 years - and your total from that period is about
4% of the remaining stock (and in a commercial operation, to boot, not
hobbyist)...

> If you going to build a board or three maybe even 20 its not a big deal
> but its not a reliable source of predictable quality.

Sure, but try looking at it from our perspective: we either use an
out-of-production part, or have to design something (almost certainly from
discretes) that meets those specs; and we actually looked at the latter (viz.
Dave B's design). However, after some pondering, and taking everything
(including all the below) into account, we decided to go with the original
chips, since they were still sorta available.

Which is why both we and Guy have stocked up on them, at the start of the
process: we don't want to crank out boards designed for a certain part, and
then not be able to get the out-of-production parts the boards were designed
to use.

If we were designing something for serious production, that wouldn't be an
option, but for limited-volume hobbyist use, it is. The choice of an
out-of-production part does have a down-side, but it's minor (and mostly
alleviated by the pre-buying), and the other options were (in overall sum)
worse.

> If you get to the bridge your talking redesign in reality or an
> expensive buy from unreliable source then testing them in bulk.

But, but... I'm _already_ buying them from unreliable sources, then testing
them! :-)

But to be serious - if the demand for QSIC's, etc, runs the well of DS8641's
dry, yes, we'll probably have to re-design. In other words, we'd be right
where we'd be today if we decided not to use out-out-production parts.

Noel

Need to archive: GRiD Compass Computer Operating System Software

[Ian Finder]

I have not had good luck with the RuGRiD list. I am aware of it.

There are only a small handful of people there with Compass gear; It is
mostly centered around the later PC-compatible GRiD stuff.

There is one fellow with quite a lot of Compass media who has reached out
to me a couple times, but I don't get the drift he sees any urgency in
imaging the media, nor intends to share it. I have offered a hand, money,
etc.

If he does come through, I'll be very pleased, but at this point I am
trying to look elsewhere.

Steve, if you're willing to cross-post my list below and see if you have
better luck, please do.

I have never received a single response of value on that list.

- Ian


On Tuesday, October 25, 2016, Steve Hatle > wrote:

>
>
>
>  Original Message 
> Subject: Need to archive: GRiD Compass Computer Operating System
> Software
> From: Ian Finder 
> Date: Tue, October 25, 2016 7:08 pm
> To: "cctalk@classiccmp.org" 
>
> Folks, there appears to be a large GRiD-sized hole where archived copies
> of
> the Compass Computer Operating System software should be.
>
> ...
> --
>  Ian Finder
>  (206) 395-MIPS
>  ian.fin...@gmail.com
>
> >>
>
> There's a fairly active GRiD list at
>
> http://groups.yahoo.com/group/rugrid-laptop/
>
> You may wish to cross-post there, or I can if you don't wish to join up.
>
> Steve
>


-- 
   Ian Finder
   (206) 395-MIPS
   ian.fin...@gmail.com

Re: Need to archive: GRiD Compass Computer Operating System Software

[william degnan]

On Wed, Oct 26, 2016 at 1:32 PM, Ian Finder  wrote:

> I have not had good luck with the RuGRiD list. I am aware of it.
>
> There are only a small handful of people there with Compass gear; It is
> mostly centered around the later PC-compatible GRiD stuff.
>
>
Jut for the record, I took a look, I have a copy of GRID OS 3.1.0 A and
Management tools 3.1.0 on 5 1/4".  These are found in the back of my
Managment Tools Reference April 1984

Bill

Re: Reasonable price for a complete SOL-20 system?

[Terry Stewart]

>
> >Oh yes, the styling is clearly very similar. I like the built-in tape
> drive. Do you think that was likely inspired by the Commodore Pet?
>

It could have been.  I think EACA were looking at something people could
just pick up, take home and use without extra cables and "other bits".
This is why as well as a built-in tape deck there was also and RF
modulator, so it could be plugged straight into a (or "the) home TV.

Terry (Tez)

Re: Need to archive: GRiD Compass Computer Operating System Software

[Santo Nucifora]

Hi Ian,

This is a little pricey but this came up on Craigslist recently.

http://boston.craigslist.org/sob/sys/5839406174.html

Looks to be lots of documentation but I don't know the seller nor am I even
close by.  Maybe a group buy might net the manuals/software.  I'd be in for
the Compass 1109 but who knows the condition of the equipment.

Santo

On Wed, Oct 26, 2016 at 3:32 PM, william degnan 
wrote:

> On Wed, Oct 26, 2016 at 1:32 PM, Ian Finder  wrote:
>
> > I have not had good luck with the RuGRiD list. I am aware of it.
> >
> > There are only a small handful of people there with Compass gear; It is
> > mostly centered around the later PC-compatible GRiD stuff.
> >
> >
> Jut for the record, I took a look, I have a copy of GRID OS 3.1.0 A and
> Management tools 3.1.0 on 5 1/4".  These are found in the back of my
> Managment Tools Reference April 1984
>
> Bill
>

Looking for informer 213 VT100 roms

[Ian Finder]

I picked up an Informer 213 from eBay this week, but it has the IBM rom
set! Noo!

Anyone out there with the VT100 version willing to dump the roms for me?

Thanks,

- Ian


-- 
   Ian Finder
   (206) 395-MIPS
   ian.fin...@gmail.com

HP-1000 12044A 12825A HDLC Interface manuals available anywhere?

[Glen Slick]

I don't see these manuals online at either bitsavers.org or hpmuseum.net.

Does anyone have copies of them available?

12044-90001 HDLC Direct Connect Interface Hardware Reference Manual
(12044A for A/L-Series)

12825-90001 HDLC Direct Connect Interface Hardware Reference Manual
(12825A for M/E/F-Series)


I have more than one HP-1000 CPU. Just curious what it would take to
connect some of them together running 91750A DS/1000-IV software.

Re: Need to archive: GRiD Compass Computer Operating System Software

[Ian Finder]

I already bought the 1109 and most of the docs :)
It's what prompted my post here.
The docs are great, but there is not much software.

The seller is a good guy, very easy to work with- did a great job letting
me know what's there and what's not.
I passed on any docs I have dupes of.

On Wed, Oct 26, 2016 at 5:02 PM, Santo Nucifora 
wrote:

> Hi Ian,
>
> This is a little pricey but this came up on Craigslist recently.
>
> http://boston.craigslist.org/sob/sys/5839406174.html
>
> Looks to be lots of documentation but I don't know the seller nor am I even
> close by.  Maybe a group buy might net the manuals/software.  I'd be in for
> the Compass 1109 but who knows the condition of the equipment.
>
> Santo
>
> On Wed, Oct 26, 2016 at 3:32 PM, william degnan 
> wrote:
>
> > On Wed, Oct 26, 2016 at 1:32 PM, Ian Finder 
> wrote:
> >
> > > I have not had good luck with the RuGRiD list. I am aware of it.
> > >
> > > There are only a small handful of people there with Compass gear; It is
> > > mostly centered around the later PC-compatible GRiD stuff.
> > >
> > >
> > Jut for the record, I took a look, I have a copy of GRID OS 3.1.0 A and
> > Management tools 3.1.0 on 5 1/4".  These are found in the back of my
> > Managment Tools Reference April 1984
> >
> > Bill
> >
>



-- 
   Ian Finder
   (206) 395-MIPS
   ian.fin...@gmail.com

Re: HP-1000 12044A 12825A HDLC Interface manuals available anywhere?

[Al Kossow]

I've got this. will see about getting it on line


On 10/26/16 6:58 PM, Glen Slick wrote:

> 12044-90001 HDLC Direct Connect Interface Hardware Reference Manual
> (12044A for A/L-Series)
> 

Hitachi 303 Analog Computer Manual

[Kyle Owen]

I scanned my copy of the Hitachi 303 manual a few weeks ago. For anyone
interested in downloading it, I uploaded it here:
https://drive.google.com/open?id=0B8Ow1Wo1rBQUSVdXQU84SWtVRFU

Didn't see it on Bitsavers yet, so I thought I would share.

Thanks,

Kyle

Re: Hitachi 303 Analog Computer Manual

[drlegendre .]

Mighty right of you, Kyle.. thanks!

On Wed, Oct 26, 2016 at 10:13 PM, Kyle Owen  wrote:

> I scanned my copy of the Hitachi 303 manual a few weeks ago. For anyone
> interested in downloading it, I uploaded it here:
> https://drive.google.com/open?id=0B8Ow1Wo1rBQUSVdXQU84SWtVRFU
>
> Didn't see it on Bitsavers yet, so I thought I would share.
>
> Thanks,
>
> Kyle
>

Re: HP-1000 12044A 12825A HDLC Interface manuals available anywhere?

[Curious Marc]

I'm interested too, I have the interfaces.
Marc


> On Oct 26, 2016, at 6:58 PM, Glen Slick  wrote:
> 
> I don't see these manuals online at either bitsavers.org or hpmuseum.net.
> 
> Does anyone have copies of them available?
> 
> 12044-90001 HDLC Direct Connect Interface Hardware Reference Manual
> (12044A for A/L-Series)
> 
> 12825-90001 HDLC Direct Connect Interface Hardware Reference Manual
> (12825A for M/E/F-Series)
> 
> 
> I have more than one HP-1000 CPU. Just curious what it would take to
> connect some of them together running 91750A DS/1000-IV software.

Re: DEC bus transceivers

[allison]

On 10/26/16 10:54 AM, Noel Chiappa wrote:

 > From: Philipp Hachtmann

 > Very enlightening.
 > You're hoarding interface ICs with commercial second thoughts

If you think either Guy, or Dave and I, expect to make much money selling the
QBUS/UNIBUS boards we are working on, you are seriously confused. None of us
are in this as a money-making exercise; there are easier ways to make a lot
more money.

I was making money,  not on part but refubished and tested boards.

Allison



And as to the hoarding, if you'd like to buy up a couple of thousand yourself,
from that miniscule stockpile of 30K units that Guy and I have left out there
for you all, please let me know, and I'll expidite over a name, phone number,
and email for you to contact.

Noel

Re: DEC bus transceivers

[allison]

On 10/26/2016 12:40 PM, Noel Chiappa wrote:
> Re: DEC bus transceivers
> > From: allison
>
> > Actually since about 1987 I've used about 1200 pieces of the 8641 alone
> > repairing boards at the commercial level.
>
> Well, that's over almost 30 years - and your total from that period is about
> 4% of the remaining stock (and in a commercial operation, to boot, not
> hobbyist)...
Its also a lot of boards fixed and sold.  It was a good second income.
that has consumed about 40% of what i have and that doesn't include
the rare like DC03/4/5/10 and others some more common like DLART,
T11, DCK-11-series, and w95xx boards.

I had the gift of being a central engineering milrat at DEC.  So many
of the design protocols for many of the DEC buses are hardwired in
my brain.  They were building systems not just boards.

> > If you going to build a board or three maybe even 20 its not a big deal
> > but its not a reliable source of predictable quality.
>
> Sure, but try looking at it from our perspective: we either use an
> out-of-production part, or have to design something (almost certainly from
> discretes) that meets those specs; and we actually looked at the latter (viz.
> Dave B's design). However, after some pondering, and taking everything
> (including all the below) into account, we decided to go with the original
> chips, since they were still sorta available.

If you use the DEC part you don't have to design, its plug and go. 
Design means
you evaluated something and its application and went with it as it met the
defined need.

I've done the latter and have many tubes of parts that work quite well.
All the designs I did that were unique ground up used those as the packages
work as expected.  The key is thresholds and current sink.

Having measured parts both dynamic and static I have a good feel for
what will
work in all but the pathological cases.   For the pathological cases the
biggest
issue is current sink. But like I said there are systems I run and do
not to try
and make meet DEC supportable configuration standards which means
things like third party cards and one-offs  and those that are museum
level stock to the bone.

> Which is why both we and Guy have stocked up on them, at the start of the
> process: we don't want to crank out boards designed for a certain part, and
> then not be able to get the out-of-production parts the boards were designed
> to use.
>
> If we were designing something for serious production, that wouldn't be an
> option, but for limited-volume hobbyist use, it is. The choice of an
> out-of-production part does have a down-side, but it's minor (and mostly
> alleviated by the pre-buying), and the other options were (in overall sum)
> worse.
>
> > If you get to the bridge your talking redesign in reality or an
> > expensive buy from unreliable source then testing them in bulk.
>
> But, but... I'm _already_ buying them from unreliable sources, then testing
> them! :-)

Therein lies the problem.  My purchase was back when the largest network
was still owned by DEC.  and it was the year they were just EOL'ed
(every one
was doing last time buys with lead times of twenty plus weeks.  I've
dealt in
the grey market and  for other things I can say often the profit taking is
extreme and they know the barrel your over.

>
> But to be serious - if the demand for QSIC's, etc, runs the well of DS8641's
> dry, yes, we'll probably have to re-design. In other words, we'd be right
> where we'd be today if we decided not to use out-out-production parts.
Likely the redesign would be more along the line of different package
(maybe smaller) and the odd inversion or not.


Allison