Hi all,
I recently acquired a very nice decwriter III and it seems in good nick. However, the self test "hangs" on the return direction of the second line. Here is a video on it:
https://youtu.be/pj6rk5Dlnbk
Anyone have any ideas where to look? In local mode, it appears to work properly. I haven't tried any external serial connection yet.
73 Eugene W2HX
My Youtube Channel: https://www.youtube.com/@w2hx/videos
Fellow nerds,
not sure who knows about this project, so here an announcement ... again?
As QBUS PDP-11s (03,23,73,83,93, also uVAX) don't have lots of
lamps&switches
like the old UNIBUS machines, their owners suffer on "Blinkenlight envy".
So I was pushed to pimp up the QBUS diagnostic adapter "QProbe"
https://www.retrocmp.com/tools/qprobe
Model "QProbe2023" has now focus on entertainment.
There's a QBUS signal display in style of old PDP-10/12/15 rack header
panels.
It can be build into a 5.25" drive case ... or into the BA23 case itself.
https://www.retrocmp.com/tools/qprobe/327-qprobe2023-overview
By lucky incident you can even see the idle loop pattern of RSX11M+ on some
J11 systems. See a full boot of RSX11M+ at time index 5:56 of
https://www.youtube.com/watch?v=ajAcxGwK-vQ
As it also has RESTART/HALT/AUX switches, it's also helpful for PDP-11s
mounted
case-less in a standalone backplane (like the one at
https://retrocmp.com/projects/lsibox and on the "Frankenstein" video
https://www.youtube.com/watch?v=hoW7Szkppww&t=403s )
Btw for unknown reasons, I cannot register to classiccmp itself ... CC
me direct in your replies.
kind regards,
Joerg
Hi Jon!
> think the Bendix G-15 had cassettes for the 5-level tape
> they used.
Aha, interesting! Did a short search, but have not been able to
find a picture of a casette. Just a pile of paper tape instead ;-)
https://images.app.goo.gl/HYqkpYHJUxZeGfiA8
> of mylar tape instead of paper. OS boot tapes might be punched
> on that.
Yes, for heavy use (and e.g. humid environments), the mil guys obviously
used Mylar or heavily oiled tape. Although not experrienced myself, I was
told that the Mylar tape cuts through the guiding pins of the readers over
time. And yes, it also may easily cut one's fingers ;-)
> much like plain paper tape, and simple mylar alone. The latter often
> comes metallized on one side, and is glossy.
Yes, that is the one within the casette and the aluminum as you expect
is for optical reading (Most plastics including Mylar are quite
transparent for IR light and in the old days, when thungsten bulbs
where used, the IR part of the light was the major part contributing
to the response of the photodiodes!
> input medium for the university mainframe computer (Electrologica X8),
> they used optical readers rated at 2000 characters per second.
Wow - that is indeed pretty fast!!! My FACIT is 1200cps maximum and
stopping "on character" as it is called is VERY hard at that speed.
But buffering helps here and in case of the 920M, the casette is
used for, there was no buffering. So software needs to be read in
one run.
Best wishes,
Erik.
''~``
( o o )
+--------------------------.oooO--(_)--Oooo.-------------------------+
| Dr. Erik Baigar Inertial Navigation & |
| Salzstrasse 1 .oooO Vintage Computer |
| D87616 Marktoberdorf ( ) Oooo. Hobbyist / Physicist |
| erik(a)baigar.de +------\ (----( )---------------------------+
| www.baigar.de | \_) ) /
+----------------------+ (_/
Hi Paul,
thanks for your answer and the interesting links...
> > Aha, interesting! Did a short search, but have not been able to
> > find a picture of a casette. Just a pile of paper tape instead ;-)
> >
> > https://images.app.goo.gl/HYqkpYHJUxZeGfiA8
>
> Bitsavers has a collection of G-15 manuals. For a picture of an
> open cassette, see PDF page 27 in http://bitsavers.org/pdf/bendix/g-15/60061400_G15D_Parts_Manual.pdf.
Ahh OK, I see. But that is not a hermetically sealed casette
suitable for outdoor use in windy, rainy weather like the
one on my desk.
As the thread deviated meanwhile, I guess the Elliott Mylar
tape casette is a unique leftover from the old days ;-)
Best wishes,
Erik.
''~``
( o o )
+--------------------------.oooO--(_)--Oooo.-------------------------+
| Dr. Erik Baigar Inertial Navigation & |
| Salzstrasse 1 .oooO Vintage Computer |
| D87616 Marktoberdorf ( ) Oooo. Hobbyist / Physicist |
| erik(a)baigar.de +------\ (----( )---------------------------+
| www.baigar.de | \_) ) /
+----------------------+ (_/
Hi there - recently I posted a small video on a rugged
paper tape casette...
https://www.youtube.com/watch?v=O2jnThYsPKc
I wonder whether anyone kows if someone else had the idea
of putting paper/mylar tape into a casette for repeated use
e.g. to load an OS or similar.
Best wishes,
Erik.
''~``
( o o )
+------------------------.oooO--(_)--Oooo.---------------------------+
| Dr. Erik Baigar Inertial Navigation & |
| Salzstrasse 1 .oooO Vintage Computer |
| D87616 Marktoberdorf ( ) Oooo. Hobbyist / Physicist |
| erik(a)baigar.de +----\ (----( )-----------------------------+
| www.baigar.de | \_) ) /
+----------------------+ (_/
I have some 8-bit ISA 53c90a based SCSI controllers labeled "SCSI HB A8".
Mine are made by "Advanced Information Concepts", but apparently they were
also made by "Control Concepts". Unfortunately, mine don't have the BIOS
chips installed. I have a picture of the card with a chip installed
labeled "Ver-3.02 CCI 0991", so I know an 8k or 16k boot prom existed.
Does anyone have such a card that they'd be willing to dump a prom image
from (or let me borrow it to dump).
KJ
A bit of an odd one….
I’m trying to figure out what type of computers ran Mexico’s infamous SNIPE
electoral vote system in 1988. I have an LA Times article from 1994 talking
about how the NEW system was RS/6000-based. But this was a system built in
1987-1988. Narcos Mexico had a pretty re-creation but I didn’t spy any
brand names. Any ideas? I figure there may be photos or press releases from
that time but my Google-fu (and español) is weak.
-Jon
+44 7792 149029
When I was at the VCF SoCal last weekend I met a gentleman who was looking
for someone with Zilog Z180 assembly language experience. He says he needs
someone to rewrite code in what sounds like some kind of terminal server
product he sells(?) to convert the protocol it uses from Televideo format
to ANSI (because Televideo is getting harder to support). This gentleman
said he has a modest budget for the project.
Let me know if you might be particularly qualified and interested and I'll
put you in touch with him and you can go from there.
Sellam
Has anyone used it or something contemporaneous?
Is it at all applicable to any degree to today's approach to AI/machine learning tasks? I would like to perhaps eventually create a game, probably not chess, lilely something simpler. The old expert system modeling paradigm seems to have largely if not entirely fallen out of favor. From what I'm reading though TP seems to be geared for that.
I bought a copy at a mall in Nashville TN some 30+ years ago. I was
working at an airline at the time and was interested in the crew scheduling
problem, as well as all things AI related. I never got too far using
Prolog on that particular problem. I found the disks and manual like 13
years ago and made a short video and put it on youtube. Turbo Prolog was
pretty speedy even on old hardware.
https://www.youtube.com/watch?v=svcxu0xiH34
Win
