Re: More mystery recycler boards - DEC, Fujitsu(??), Cipher, Emulex

[Mark Linimon]

On Mon, Sep 05, 2016 at 04:48:43PM -0500, Jules Richardson wrote:
> I'm up in Bemidji, MN

Heh, I was just there a couple of months ago.

mcl

Re: The huge lot that had the NIB 8" floppies is now on ebay

[Mark Linimon]

On Mon, Sep 05, 2016 at 10:56:24PM -0500, j...@cimmeri.com wrote:
> If there's ever a vote taken up for whether to ban the constant billboarding
> of ebay ads here, I'm for "ban."

I would subscribe to a spin-off list that was merely for buy/sell/trade.

mcl

Raised floor to be available for pickup in Sewell, NJ

[Connor Krukosky]

Hi all, as per the subject some raised floor is about to become available.
As much as I wanted and was going to grab this flooring myself, I can't.

So this is the time for someone else who needs around 500-600 Sq.Ft. of 
raised flooring to go get it!
This flooring is about 8in tall, so its not anything crazy like some of 
the newer taller stuff.


The floor MAY be available, he is not 100% sure yet.
The deal is they are selling the building and if the new owners do not 
want it, it is for grabs but must be picked up in the next 2-3 weeks.

I am not sure, but you probably have to grab it all.

The floor is located in Sewell, NJ as per the subject.
It will be available for low or no cost depending on the interest level...

Please contact Mike at:
mbrotzman@gmail.com

-Connor Krukosky

Re: The huge lot that had the NIB 8" floppies is now on ebay

[jim stephens]

Yes, we do.  I had not found this ad and it is in Kansas City, where I 
have a warehouse.


Cindy, I didn't see the 8" floppies though.  I also thought this was in 
Colorado, but see it listed as KC now, though that may only be another 
auction.  This unfortunately isn't up my alley for collecting.

thanks
jim

On 9/5/2016 8:56 PM, j...@cimmeri.com wrote:


If there's ever a vote taken up for whether to ban the constant 
billboarding of ebay ads here,
I'm for "ban."   People who know how to use ebay do not need help 
finding things on ebay.

COMPUTERS: THEIR IMPACT ON SOCIETY, AFIPS Conference Proceedings, Volume 27, Pa

[COURYHOUSE]

extra copy  no DJ ex lib  tight binding unmarked  text   pages aside  from 
library stamps  etc
trade or? repy offlist  Ed#  SMECC www.smecc.org
_
COMPUTERS: THEIR IMPACT ON SOCIETY, AFIPS  Conference Proceedings, Volume 
27, Part 2, 1965 Fall Joint Computer  Conference.
_ 
(https://www.amazon.com/COMPUTERS-Conference-Proceedings-Computer-Conference/dp/B000KIFENU/ref=sr_1_4?s=books=UTF8=1473133415=1-4=c
omputers+their+impact+on+society) 1967

Re: The huge lot that had the NIB 8" floppies is now on ebay

[j...@cimmeri.com]

If there's ever a vote taken up for whether to ban the constant 
billboarding of ebay ads here,
I'm for "ban."   People who know how to use ebay do not need help 
finding things on ebay.



On 9/5/2016 10:31 PM, Electronics Plus wrote:

http://www.ebay.com/itm/-/191960867958



Apparently the buyer backed out, and the entire lot is now available as ONE
lot. There is no reserve.



Cindy Croxton

The huge lot that had the NIB 8" floppies is now on ebay

[Electronics Plus]

http://www.ebay.com/itm/-/191960867958

 

Apparently the buyer backed out, and the entire lot is now available as ONE
lot. There is no reserve.

 

Cindy Croxton

 

 

Re: PDP-8 core memory problems.

[Jon Elson]

On 09/05/2016 09:28 PM, Brent Hilpert wrote:


I'd tend to be more pessimistic about this working.


In the 3-wire example there you can see how the S/I wire was split in half with 
a special resistor network at one end to allow inhibit current flow
while at the same time configuring it as a balanced loop for the sense function.

My article certainly isn't the last word on the variety of implementations, I 
believe there were 4-wire designs with sense wires parallel to
select wires as in the 3-wire designs for example, so you never know until you 
examine the specifics at hand,
but I think it unlikely you'd have much success getting the inhibit wire to 
function for sense, not without going to as much trouble
messing with the stack as if you tried to fix the sense wire.
Well, older core memories had larger cores, which slowed 
everything down as well as gave much bigger pulses when a 
core flipped.  That might make this exercise a bit easier.

If the sense wire is open I'd guess there's a good chance it's at one of the 
end points where it's soldered to a terminal or at an existing splice
from manufacture time and might be repairable if access could be had.
But, he has to split the whole stack to at least access the 
bad plane from one side.  Already a pretty daunting 
exercise.  Still, fixing the bad wire, if the break is at an 
exposed point, would be preferable than re-engineeering the 
whole sense-inhibit circuitry. If the wire can be fixed, 
there would be no engineering required.


I saw our old IBM 7094 memory, which had a combination of 
tube and transistor circuitry, and one inhibit (or maybe 
sense) wire had been burned up by a failed circuit.  The 
cores kept the wire cool, so the only places it opened was 
where the wire looped around the plane. There were dozens of 
bits of wire soldered to fix the places where it opened.  
Sheesh, I sure wouldn't have wanted to be the CE who had to 
do that repair!


Jon

Re: PDP-8 core memory problems.

[Brent Hilpert]

On 2016-Sep-05, at 4:36 PM, Jon Elson wrote:
> On 09/05/2016 05:46 PM, Mattis Lind wrote:
>> måndag 5 september 2016 skrev Jon Elson :
>> 
>>> On 09/05/2016 01:59 PM, Mattis Lind wrote:
>>> 
 I have now concluded that the fault is in the core memory module itself.
 The sense winding is broken on bit plane 7.
 
 
 Have you actually ohmed out the sense/inhibit wire?
>> This is by the way a four wire stack. Separate sense and inhibit wire.
> OH!  I didn't know any PDP-8 had 4-wire planes.  Very interesting. Hmmm, you 
> could rig a pulse transformer to the inhibit wire to bring signals over to 
> the sense amp.
>> Come to think of it, since the inhibit wire is OK, would it be possible to
>> arrange it as a three wire stack somehow. Change the sense amp and inhibit
>> drivers so that they use the same wire?
> Ah, you already thought of that.  Well, it SHOULD be possible. You'd probably 
> put a resistor in series with the pulse transformer so that all the select 
> current went through the inhibit wire.  Then, the only problem would be that 
> the sense amp gets hit with a big pulse during the writeback.  As long as the 
> sense amp recovers from the overload before the next read cycle, it ought to 
> work.  Some 4-wire planes were set up so the polarity of half the sense wires 
> were opposite to the inhibit, so the coupled inhibit current balanced out to 
> zero in the sense winding.  Any mid-sized 1:1 pulse transformer should do the 
> coupling, the currents might be pretty high, but the duration isn't very 
> long.  (Minor nit, the inhibit wires only get pulsed one direction, so you 
> might need a resistive path across the secondary to discharge the flux build 
> up so it doesn't saturate.)
>> Maybe Brent can come in with some advice if this is possible or just
>> stupid.
> It is NOT stupid, I think it could really work!

I'd tend to be more pessimistic about this working.

There are different requirements in winding a wire for purposes of inhibit and 
sense.
In the 3-wire arrangement the winding of the combined wire has to meet both
sets of requirements.

Specifically, for this case, in a 4-wire mem, where the inhibit wire was woven 
just for
the purposes of inhibit, I don't anticipate it's going to have the noise 
cancellation topology
needed to function as the sense wire.

Sense wires were woven as a floating loop feeding a differential amplifier. The 
loop is kept
quite closed or otherwise woven in a very balanced manner so that the magnetic 
fields from the
large select currents (and other influences) will cancel out or be rejected as 
common-mode influence at the
differential amp inputs.

The select current magnetic fields trigger the magnetic field reversal of the 
core, you want to sense the latter distinct from the former.
Unless you have circuitry with the wherewithal to distinguish those induced 
currents in the sense wire in time
(delay of the core field reversal from the select field), you otherwise have to 
minimise the influence of the select current fields on the sense wire.

If you look at the diagrams in my article you can see the sorts of differences 
in weaving topologies between 3 & 4 wire arrangements, 
as well as examples of the tortured topologies resorted to to balance the sense 
loop.
In the 3-wire example there you can see how the S/I wire was split in half with 
a special resistor network at one end to allow inhibit current flow
while at the same time configuring it as a balanced loop for the sense function.

My article certainly isn't the last word on the variety of implementations, I 
believe there were 4-wire designs with sense wires parallel to
select wires as in the 3-wire designs for example, so you never know until you 
examine the specifics at hand,
but I think it unlikely you'd have much success getting the inhibit wire to 
function for sense, not without going to as much trouble 
messing with the stack as if you tried to fix the sense wire.

If the sense wire is open I'd guess there's a good chance it's at one of the 
end points where it's soldered to a terminal or at an existing splice
from manufacture time and might be repairable if access could be had.

Might the stack have a parity bit array that could be redirected to replace the 
faulty bit array?,
perhaps foregoing the parity checking on that board-set if the parity logic is 
present.

Re: PDP-8 core memory problems.

[Jon Elson]

On 09/05/2016 05:46 PM, Mattis Lind wrote:

måndag 5 september 2016 skrev Jon Elson :


On 09/05/2016 01:59 PM, Mattis Lind wrote:


I have now concluded that the fault is in the core memory module itself.
The sense winding is broken on bit plane 7.


Have you actually ohmed out the sense/inhibit wire?

This is by the way a four wire stack. Separate sense and inhibit wire.
OH!  I didn't know any PDP-8 had 4-wire planes.  Very 
interesting. Hmmm, you could rig a pulse transformer to the 
inhibit wire to bring signals over to the sense amp.

Come to think of it, since the inhibit wire is OK, would it be possible to
arrange it as a three wire stack somehow. Change the sense amp and inhibit
drivers so that they use the same wire?
Ah, you already thought of that.  Well, it SHOULD be 
possible. You'd probably put a resistor in series with the 
pulse transformer so that all the select current went 
through the inhibit wire.  Then, the only problem would be 
that the sense amp gets hit with a big pulse during the 
writeback.  As long as the sense amp recovers from the 
overload before the next read cycle, it ought to work.  Some 
4-wire planes were set up so the polarity of half the sense 
wires were opposite to the inhibit, so the coupled inhibit 
current balanced out to zero in the sense winding.  Any 
mid-sized 1:1 pulse transformer should do the coupling, the 
currents might be pretty high, but the duration isn't very 
long.  (Minor nit, the inhibit wires only get pulsed one 
direction, so you might need a resistive path across the 
secondary to discharge the flux build up so it doesn't 
saturate.)

Maybe Brent can come in with some advice if this is possible or just
stupid.

It is NOT stupid, I think it could really work!

Jon

Re: PDP-8 core memory problems.

[Mattis Lind]

måndag 5 september 2016 skrev Jon Elson :

> On 09/05/2016 01:59 PM, Mattis Lind wrote:
>
>>
>> I have now concluded that the fault is in the core memory module itself.
>> The sense winding is broken on bit plane 7.
>>
>>
>> Have you actually ohmed out the sense/inhibit wire?
>

This is by the way a four wire stack. Separate sense and inhibit wire.

Come to think of it, since the inhibit wire is OK, would it be possible to
arrange it as a three wire stack somehow. Change the sense amp and inhibit
drivers so that they use the same wire?

Maybe Brent can come in with some advice if this is possible or just
stupid. I promise to read his excellent article on core memories once again
tomorrow when I am less tired to see If I can figure something out...

Re: More mystery recycler boards - DEC, Fujitsu(??), Cipher, Emulex

[Adrian Graham]

On 05/09/2016 22:48, "Jules Richardson" 
wrote:

> On 09/02/2016 04:40 PM, Dave Wade wrote:
>> Jules,
>>   Where in the world are these...
> 
> I'm up in Bemidji, MN
> 
> I've been here almost ten years and not seen any DEC stuff until those
> boards came in a few weeks ago. These latest ones were supposedly turned in
> at the recycler by a different person, which makes it quite strange.
> 
> I think I'll see about getting the M8014, M8012, M8013 and M8061 boards
> tomorrow. The rest can probably go for scrap.

I wonder how much shipping would be for the VT100 board...

-- 
Adrian/Witchy
Binary Dinosaurs creator/curator
Www.binarydinosaurs.co.uk - the UK's biggest private home computer
collection?

Re: PDP-8 core memory problems.

[Mattis Lind]

måndag 5 september 2016 skrev Jon Elson :

> On 09/05/2016 01:59 PM, Mattis Lind wrote:
>
>>
>> I have now concluded that the fault is in the core memory module itself.
>> The sense winding is broken on bit plane 7.
>>
>>
>> Have you actually ohmed out the sense/inhibit wire?


Yes. I have measured at at the tabs where the red arrow points in the image
below:

http://i.imgur.com/x5VVh2F.jpg

Unfortunately I am pretty sure that this will rule out pulse transformers
or whatever.

/Mattis

Re: Apple IIGS on epay - local pickup in Seattle

[Eric Christopherson]

On Sep 5, 2016 2:36 PM, "Eric Christopherson" 
wrote:
>
> On Sep 5, 2016 1:21 PM, "Glen Slick"  wrote:
> >
> > On Sep 5, 2016 11:07 AM, "Eric Christopherson" <
echristopher...@gmail.com>
> > wrote:
> > >
> > > Anyone want this? Less than 4 his remaining.
> > >
> > > Actually I'd love to have someone win it for me and sell it to me at
> > VCFMW,
> > > but I've never arranged such a thing so I don't know what to estimate
the
> > > cost to me would be. (Plus it probably won't stay at $49 for long.)
I'd
> > bid
> > > on it myself and then worry about getting it to me, but they
explicitly
> > day
> > > they don't accept third-party shippers.
> >
> > Item 401179185305 at Seattle Goodwill? Where are you located?
>
> Yes, that's the one. Sorry, just forgot to paste the link - - wasn't
trying to keep others from finding it.
>
> http://m.ebay.com/itm/401179185305?_mwBanner=1
>
> >
> > If you bid and won you could probably get someone on the list to pick
it up
> > for you and ship it to you after you paid for the item and the shipping.
> >
> > -Glen

I didn't manage to win it, but Seattle Goodwill did tell me they would be
fine with having someone pick it up for me.

It only doubled in price... Pity.

Re: More mystery recycler boards - DEC, Fujitsu(??), Cipher, Emulex

[Jules Richardson]

On 09/02/2016 04:40 PM, Dave Wade wrote:

Jules,
  Where in the world are these...


I'm up in Bemidji, MN

I've been here almost ten years and not seen any DEC stuff until those 
boards came in a few weeks ago. These latest ones were supposedly turned in 
at the recycler by a different person, which makes it quite strange.


I think I'll see about getting the M8014, M8012, M8013 and M8061 boards 
tomorrow. The rest can probably go for scrap.


cheers

Jules

Re: vt100 terminfo with padding for an actual vt100?

[Peter Coghlan]

Warner Losh wrote:
>On Mon, Sep 5, 2016 at 10:30 AM, Peter Coghlan  wrote:
>>>
>>> The usual answer, from back in the day, was to make sure hardware flow
>>> control was on and working at higher speeds. If you don't have that,
>>> you are going to lose > 9600 baud. I spent way too much time pulling
>>> fat cable to enable this after we'd wired the building with 3-wire
>>> cable for the VT52's and cute 'headphone' plug-in jacks back in my
>>> high school days...
>>>
>>
>> Generally, DEC didn't have hardware flow control at that time because it was
>> not in the standard.  I'm pretty sure there was no hardware flow control
>> available on the VT100.  It used XON/XOFF.
>
> I may be misremembering when we did this: with the VT100, VT102 or VT220's.
>

I may be misremembering too but my feeling is that it was much later on than
that even when DEC only reluctantly began to offer RTS/CTS hardware flow
control on terminal servers in order to support "high speed" async modems.

As far as I recall, big bunches of serial ports on a VAX etc had gone away
in favour of network attached terminal servers before that time and I don't
think the directly attached serial ports ever provided hardware flow control.
They could optionally provide "modem control" though, in that they could
signal a modem to hang up and the modem could signal the machine that a
connection had been established or gone away.

I had a look in the VT102 guide and it explicitly says that there are only
three ways of avoiding buffer overruns - XON/XOFF, fill characters and using
a lower speed.

On the other hand, it also says that the VT102 printer port can respond to DSR
being dropped by stopping sending characters to it.  It suggests that the
printer can drop DTR when it's buffers are full and this should be wired to
DSR on the terminal printer port so there is hardware flow control available
there at least.

Regards,
Peter Coghlan.

Re: Apple IIGS on epay - local pickup in Seattle

[Eric Christopherson]

On Sep 5, 2016 1:21 PM, "Glen Slick"  wrote:
>
> On Sep 5, 2016 11:07 AM, "Eric Christopherson" 
> wrote:
> >
> > Anyone want this? Less than 4 his remaining.
> >
> > Actually I'd love to have someone win it for me and sell it to me at
> VCFMW,
> > but I've never arranged such a thing so I don't know what to estimate
the
> > cost to me would be. (Plus it probably won't stay at $49 for long.) I'd
> bid
> > on it myself and then worry about getting it to me, but they explicitly
> day
> > they don't accept third-party shippers.
>
> Item 401179185305 at Seattle Goodwill? Where are you located?

Yes, that's the one. Sorry, just forgot to paste the link - - wasn't trying
to keep others from finding it.

http://m.ebay.com/itm/401179185305?_mwBanner=1

>
> If you bid and won you could probably get someone on the list to pick it
up
> for you and ship it to you after you paid for the item and the shipping.
>
> -Glen

PDP-8 core memory problems.

[Mattis Lind]

For some time I have slowly been working on restoring our PDP-8 to
operating condition.

Here are some notes on the progress:
http://www.datormuseum.se/computers/digital-equipment-corporation/pdp-8

It is sort of working now after reforming capacitors in the PSU, adjusting
memory currents and replacing a 2N3639 in a MA, MB, PC (R211) board.

But bit seven is still showing a 0 when trying to set it. I found an old
note that I wrote somewhere in 1990 that indicated the same problem was
present then as well so it hasn't happen lately.

I have now concluded that the fault is in the core memory module itself.
The sense winding is broken on bit plane 7.

So what are my options?

What are the chances that a repair is successful? It looks really complex
to take it appart and get to to layer seven. Then to find the broken wire,
somehow replace it and splice it together with the rest of the sense
winding... Not an everyday job.

Does anyone have a known good spare module? I have some MM15 modules for
PDP-15 to trade with!

Could a MM15 module be adapted to be used instead? It is completely
different foot print and it is a three wire stack.

The Russian stacks sold on Ebay? But what guarantees are that those work at
all and can be adapted... Probably other memory currents and cycle time?

Some other technology that can be used to make up for the missing bit
plane. But what technology and how. With as little intrusion in the
machine. I don't really want to replace the entire memory system with a
battery backed SRAM...

Any ideas, thoughts or a  working PDP-8 core memory module is highly sought
for!

/Mattis

Re: Apple IIGS on epay - local pickup in Seattle

[Glen Slick]

On Sep 5, 2016 11:07 AM, "Eric Christopherson" 
wrote:
>
> Anyone want this? Less than 4 his remaining.
>
> Actually I'd love to have someone win it for me and sell it to me at
VCFMW,
> but I've never arranged such a thing so I don't know what to estimate the
> cost to me would be. (Plus it probably won't stay at $49 for long.) I'd
bid
> on it myself and then worry about getting it to me, but they explicitly
day
> they don't accept third-party shippers.

Item 401179185305 at Seattle Goodwill? Where are you located?

If you bid and won you could probably get someone on the list to pick it up
for you and ship it to you after you paid for the item and the shipping.

-Glen

Apple IIGS on epay - local pickup in Seattle

[Eric Christopherson]

Anyone want this? Less than 4 his remaining.

Actually I'd love to have someone win it for me and sell it to me at VCFMW,
but I've never arranged such a thing so I don't know what to estimate the
cost to me would be. (Plus it probably won't stay at $49 for long.) I'd bid
on it myself and then worry about getting it to me, but they explicitly day
they don't accept third-party shippers.

Re: vt100 terminfo with padding for an actual vt100?

[Warner Losh]

On Mon, Sep 5, 2016 at 10:30 AM, Peter Coghlan  wrote:
>>
>> The usual answer, from back in the day, was to make sure hardware flow
>> control was on and working at higher speeds. If you don't have that,
>> you are going to lose > 9600 baud. I spent way too much time pulling
>> fat cable to enable this after we'd wired the building with 3-wire
>> cable for the VT52's and cute 'headphone' plug-in jacks back in my
>> high school days...
>>
>
> Generally, DEC didn't have hardware flow control at that time because it was
> not in the standard.  I'm pretty sure there was no hardware flow control
> available on the VT100.  It used XON/XOFF.

I may be misremembering when we did this: with the VT100, VT102 or VT220's.

Warner

Re: vt100 terminfo with padding for an actual vt100?

[Peter Coghlan]

>
> The usual answer, from back in the day, was to make sure hardware flow
> control was on and working at higher speeds. If you don't have that,
> you are going to lose > 9600 baud. I spent way too much time pulling
> fat cable to enable this after we'd wired the building with 3-wire
> cable for the VT52's and cute 'headphone' plug-in jacks back in my
> high school days...
>

Generally, DEC didn't have hardware flow control at that time because it was
not in the standard.  I'm pretty sure there was no hardware flow control
available on the VT100.  It used XON/XOFF.

Regards,
Peter Coghlan.

Re: Y Combinator is restoring one of Alan Kay's Xerox Alto machines

[Josh Dersch]

On 9/5/16 8:55 AM, Al Kossow wrote:


This is why Alto restoration with one set of boards is extremely difficult.
The machine wasn't designed to be serviced. Almost everything has to work
before you can do anything, and there is a very high probability that in the
process of bringing it up you will corrupt the disk pack. Hopefully the ethernet
bridge boards will come through soon so you can try to etherboot a diagnostic
once you stop getting parity errors. The ECC memory subsystem is fairly 
complicated
so it wouldn't surprise me there is a problem with it. You might try reducing 
the
number of installed memory boards.
At the LCM, I used an Apple II to test out the Alto's memory -- the Alto 
II XM uses 4116 RAM chips.  I swapped in a row at a time and wrote a 
little BASIC program to test for obvious errors.  This was 
time-consuming, but eliminated the obviously bad chips, which helped 
immensely.



If you can get it to the point where it hits the
disk it should sequentially read a bunch of tracks, seek to zero, then start to 
boot
which changes the pitch of the 5v switching supply. You can tell a lot about 
what's
going on just by the sound of the power supply. If the power supply isn't 
chirping
the machine isn't doing much.
The (faint) noise patterns on the screen will also vary depending on 
what it's doing... (at least on our machines... maybe others have better 
shielding :)).


- Josh



On 9/3/16 11:08 PM, curiousma...@gmail.com wrote:

Episode 5, still does not boot, but we are starting to follow long why:
https://youtu.be/Wr7vDZpniNIr

Re: vt100 terminfo with padding for an actual vt100?

[william degnan]

On Sep 5, 2016 12:05 PM, "Peter Coghlan"  wrote:
>
> Fritz Mueller wrote:
> >
> > > On Sep 4, 2016, at 6:08 PM, william degnan 
wrote:
> > >
> > > Even better, I found this post, this is my how to attach a vt100 to a
VAX
> > > 4000, you can apply to most any case
> >
> >
> > Hi Bill,
> >
> > Thanks for you help!
> >
> > I will say that I have the getty running fine, baud rate, serial
format, etc.
> > all okay.  Works just fine at 1200 baud and below.  At higher baud
rates, it
> > seems like the vt100 is dropping some characters or bits after certain
> > escape sequences, even with xon/xoff flow control enabled, so I’m
*pretty*
> > sure the issue is just with the padding values in the vt100 terminfo
spec?
> >
>
> I've got a VT102 Video Terminal User Guide (EK-VT102-UG-003) which
contains
> a table of fill characters required for different control codes / escape
> sequences / display characters at each possible baud rate.  Here's what it
> lists for 19200 baud:
>
>  324 IND, LF, NEL, RI (Smooth Scroll)
>  191 DECCOLM
>  190 DECALN
>  144 ED (132 Col)
>  104 ED (80 Col)
>   32 IND, LF, NEL, RI (Jump Scroll)
>6 EL (132 Col)
>4 EL (80 Col)
>7 DECINLM
>2 All others except RIS and DECTST
>
> The appendix also seems to hint that the VT100 has different requirements
so
> this may not be very useful to you but it might give you a rough idea.
>
> Regards,
> Peter Coghlan.

The link I provided has exactly what keystrokes and settings to use for
8/n/1 and 19200, plus a link to the vt100 manual.  VT102 is not the same.
B

Re: vt100 terminfo with padding for an actual vt100?

[Warner Losh]

The usual answer, from back in the day, was to make sure hardware flow
control was on and working at higher speeds. If you don't have that,
you are going to lose > 9600 baud. I spent way too much time pulling
fat cable to enable this after we'd wired the building with 3-wire
cable for the VT52's and cute 'headphone' plug-in jacks back in my
high school days...

Warner

On Mon, Sep 5, 2016 at 1:24 AM, Adrian Graham
 wrote:
> On 05/09/2016 01:10, "Fritz Mueller"  wrote:
>
>> Hi all ‹
>>
>> I¹m trying to run a real-deal vt100 on a serial port connected to Linux
>> (Xubunto 16.04).  I¹ve got this working *pretty* well, but it looks like the
>> padding values in the default vt100 terminfo entry are not quite correct ‹
>> when running the vt100 at 9600 I still get occasional garbage characters on
>> the screen, and 19200 is a hopeless mess.
>>
>> I did figure out that if the terminfo contains ³xon², the non-mandatory
>> padding values in the terminfo are disregarded.  Removing this, then 
>> disabling
>> xon/xoff on both the vt100 and the tty device actually produces *better*
>> results ‹ apparently the turnaround on xon/xoff isn¹t quite fast enough to
>> keep the terminal from being swamped at higher baud rates, and padding
>> actually works better.  But tracking down the source for the default vt100
>> entry turned up a comment that admits that the padding values there are a
>> total guess. :-(
>>
>> So, before I go diving too much further into the terminfo-tweaking-samp, I
>> thought I¹d ask if anybody has a good vt100 entry already on hand?  (I¹d take
>> one for the VT52 as well!)
>
> Interesting. I'm running a genuine VT100 from a home-made serial port
> (MAX3232 based) on a Beaglebone Black running Debian Jessie as part of my
> DECbox project and it's rock solid at 9600 baud, even with smooth scroll.
> I'd never given the termcap entry a moment's thought.
>
> This may or may not help, but when talking serially to a ZX Spectrum (I
> know, but it's still RS232 comms) I get consistent results with a genuine
> serial port on a laptop but with a cheap chinese USB-serial converter it
> just doesn't work and I put this down to incorrect grounding.
>
> --
> Adrian/Witchy
> Binary Dinosaurs creator/curator
> Www.binarydinosaurs.co.uk - the UK's biggest private home computer
> collection?
>
>

Re: vt100 terminfo with padding for an actual vt100?

[Peter Coghlan]

Fritz Mueller wrote:
>
> > On Sep 4, 2016, at 6:08 PM, william degnan  wrote:
> > 
> > Even better, I found this post, this is my how to attach a vt100 to a VAX
> > 4000, you can apply to most any case
>
>
> Hi Bill,
>
> Thanks for you help!
>
> I will say that I have the getty running fine, baud rate, serial format, etc.
> all okay.  Works just fine at 1200 baud and below.  At higher baud rates, it
> seems like the vt100 is dropping some characters or bits after certain
> escape sequences, even with xon/xoff flow control enabled, so I’m *pretty*
> sure the issue is just with the padding values in the vt100 terminfo spec?
>

I've got a VT102 Video Terminal User Guide (EK-VT102-UG-003) which contains
a table of fill characters required for different control codes / escape
sequences / display characters at each possible baud rate.  Here's what it
lists for 19200 baud:

 324 IND, LF, NEL, RI (Smooth Scroll)
 191 DECCOLM
 190 DECALN
 144 ED (132 Col)
 104 ED (80 Col)
  32 IND, LF, NEL, RI (Jump Scroll)
   6 EL (132 Col)
   4 EL (80 Col)
   7 DECINLM
   2 All others except RIS and DECTST

The appendix also seems to hint that the VT100 has different requirements so
this may not be very useful to you but it might give you a rough idea.

Regards,
Peter Coghlan.

Re: Y Combinator is restoring one of Alan Kay's Xerox Alto machines

[Al Kossow]

This is why Alto restoration with one set of boards is extremely difficult.
The machine wasn't designed to be serviced. Almost everything has to work
before you can do anything, and there is a very high probability that in the
process of bringing it up you will corrupt the disk pack. Hopefully the ethernet
bridge boards will come through soon so you can try to etherboot a diagnostic
once you stop getting parity errors. The ECC memory subsystem is fairly 
complicated
so it wouldn't surprise me there is a problem with it. You might try reducing 
the
number of installed memory boards. If you can get it to the point where it hits 
the
disk it should sequentially read a bunch of tracks, seek to zero, then start to 
boot
which changes the pitch of the 5v switching supply. You can tell a lot about 
what's
going on just by the sound of the power supply. If the power supply isn't 
chirping
the machine isn't doing much.

On 9/3/16 11:08 PM, curiousma...@gmail.com wrote:
> Episode 5, still does not boot, but we are starting to follow long why:
> https://youtu.be/Wr7vDZpniNIr
> 

Re: Y Combinator is restoring one of Alan Kay's Xerox Alto machines

[Liam Proven]

On 4 September 2016 at 08:08,   wrote:
> Episode 5, still does not boot, but we are starting to follow long why:
> https://youtu.be/Wr7vDZpniNIr


I know I'm a total lightweight and a board-swapper, but the depth and
the skills involved in this troubleshooting -- let alone the actual
tools -- are leaving me in awe. Compelling viewing!


-- 
Liam Proven • Profile: http://lproven.livejournal.com/profile
Email: lpro...@cix.co.uk • GMail/G+/Twitter/Flickr/Facebook: lproven
MSN: lpro...@hotmail.com • Skype/AIM/Yahoo/LinkedIn: liamproven
Cell/Mobiles: +44 7939-087884 (UK) • +420 702 829 053 (ČR)

Re: Interact Model One Software

[Davidpopovich]

Did you ever get your interact running?

I can help you with cassettes if you need.

There is also a way to use a wav file and play through an MP3 to cassette 
adapter

Let me know

Sent from my iPhone

Re: HP-35/45 Simulator for PDP-8

[Pontus Pihlgren]

On Sun, Sep 04, 2016 at 10:43:19PM -0700, Mark J. Blair wrote:
> 
> > On Sep 4, 2016, at 21:39, Kyle Owen  wrote:
> > 
> > Just thought I'd share with you all one of my pet projects for the past few
> > years. I have written an HP-35 and HP-45 simulator for the PDP-8, which
> > uses the original microcode from these calculators. Thus, it is just as
> > accurate as the original calculators, I would believe.
> 
> That is silly, fantastic, absurd, and wonderful. All at the same time.

Agreed :) Period correct programming.

/P

Re: vt100 terminfo with padding for an actual vt100?

[Adrian Graham]

On 05/09/2016 01:10, "Fritz Mueller"  wrote:

> Hi all ‹
> 
> I¹m trying to run a real-deal vt100 on a serial port connected to Linux
> (Xubunto 16.04).  I¹ve got this working *pretty* well, but it looks like the
> padding values in the default vt100 terminfo entry are not quite correct ‹
> when running the vt100 at 9600 I still get occasional garbage characters on
> the screen, and 19200 is a hopeless mess.
> 
> I did figure out that if the terminfo contains ³xon², the non-mandatory
> padding values in the terminfo are disregarded.  Removing this, then disabling
> xon/xoff on both the vt100 and the tty device actually produces *better*
> results ‹ apparently the turnaround on xon/xoff isn¹t quite fast enough to
> keep the terminal from being swamped at higher baud rates, and padding
> actually works better.  But tracking down the source for the default vt100
> entry turned up a comment that admits that the padding values there are a
> total guess. :-( 
> 
> So, before I go diving too much further into the terminfo-tweaking-samp, I
> thought I¹d ask if anybody has a good vt100 entry already on hand?  (I¹d take
> one for the VT52 as well!)

Interesting. I'm running a genuine VT100 from a home-made serial port
(MAX3232 based) on a Beaglebone Black running Debian Jessie as part of my
DECbox project and it's rock solid at 9600 baud, even with smooth scroll.
I'd never given the termcap entry a moment's thought.

This may or may not help, but when talking serially to a ZX Spectrum (I
know, but it's still RS232 comms) I get consistent results with a genuine
serial port on a laptop but with a cheap chinese USB-serial converter it
just doesn't work and I put this down to incorrect grounding.

-- 
Adrian/Witchy
Binary Dinosaurs creator/curator
Www.binarydinosaurs.co.uk - the UK's biggest private home computer
collection?

Re: vt100 terminfo with padding for an actual vt100?

[alexmcwhirter]

Are you using a USB to serial converter? I've had tons of issues doing 
this on cheap converters. The diablo cable branded ones seems to work 
well.

Re: HP-35/45 Simulator for PDP-8

[Mark J. Blair]

> On Sep 4, 2016, at 21:39, Kyle Owen  wrote:
> 
> Just thought I'd share with you all one of my pet projects for the past few
> years. I have written an HP-35 and HP-45 simulator for the PDP-8, which
> uses the original microcode from these calculators. Thus, it is just as
> accurate as the original calculators, I would believe.

That is silly, fantastic, absurd, and wonderful. All at the same time.

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