I am an old mainframe guy. I could give you my COBOL deck of cards or the compile listing. You could pour through the code looking for nefarious/malicious code. I then hand you the object deck. You have no idea if it matches the code you looked at. The only way you could be sure is to compile the code I gave you and use your own object deck.
So why is open source these days such a beneficial thing? DeepSeek may be open source but I have no way to create my own executable. Besides, I don’t know what language it is written in but I bet I have no expertise in it. No way to for me to identify nasty code.
Yes, many people may have reviewed the code but that does not mean what I am running is the result of that code.
Hi Van,
just wanted to point out, that there is a 803 emulator out there:
https://www.peteronion.org.uk/Elliott/
I have got a real 900 series machine running, which is from the very
early 1970ies and also runs a form of Elliott Algol:
https://www.youtube.com/watch?v=v-gF5g0nnoE
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 | \_) ) /
+----------------------+ (_/
>Message: 31
>Date: Sun, 2 Feb 2025 07:29:15 +0000
>From: Tony Duell <ard.p850ug1(a)gmail.com>
>Subject: [cctalk] Re: RS232 then and now
>
>On Sat, Feb 1, 2025 at 10:54 PM Fred Cisin via cctalk
><cctalk(a)classiccmp.org> wrote:
>
>
>>
>> IBM used a DB25 socket for their printer port at the computer end,
>> (male on the card for serial, female on the card for parallel "Centronics")
>> THAT, of course caused some idiots to attempt to use the parallel port for
>> serial and vice versa. "I just need a 'gender changer'!" :-)
>
>The worst screw-up there (IMHO) came from HP in the HP150 series. This
>machine had 2 RS232 serial ports as standard on DB25 sockets, wired
>for some inexplicable reason as DTEs. There was an add-on board that
>included a parallel printer port. To avoid confusion, this was a DB25
>plug. But the board had been laid out for a DB25 socket using the IBM
>PC pinout. The result was that stb/ ended up on pin 13, D0 on pin 12,
>and so on.
>
>-tony
>
My vote for the worst connector screw-up is the AT&T (Olivetti) 6300. Its monochrome monitor used a DB25 to supply both the signals and 12 volts to power the monitor.
Bob
I was about to ask if anyone ever built a "Parallel Modem" - but I searched
around first, and lo and behold, Microcom did ! (v.fast / v.34 era, c.
1996)
The drivers refer to Win3.1/Win95 era (I'm not seeing where they had DOS
support).
But I'm still not sure if I'm understanding the product (which I found
described here
Microcom Parallel Port Modem <https://strom.com/pubwork/cw294.html>
From a programming perspective, you just set your parallel bits and mash
the STROBE pin, right? Then figure some reasonable delay between
iterations of doing that. You don't need starts/stop or parity bits. So
I get how that is more efficient (but question is, why wasn't it built
sooner? I think it's a long answer when you look at the historical build up
of modems, and that serial-port based modems were "fast enough" at the time)
So.. If you had a slow system that couldn't really take advantage of a
~7MHz 16550 serial card (or I guess like a laptop that was stuck with an
older UART) That might be the use-case where this parallel v.fast might
help (by being able to "feed the modem" fast enough to actually take
advantage of the faster modem speed?) Or is there some other scenario
NOTE, in the articled linked above, it does mention that it is only "value
added" if you have this parallel-modem on both sides of the connection.
(this is because you'll be flow controlled to whatever is the slower device
in the connection?)
Related but different question:
Is there any "natural rate" (Hz) of a modem? Meaning is 1200/2400
baud-equivalent modem an accelerated-by-enhanced-encoding version of 300
bps? and 9600 likewise an accelerated-by-encoding version of 2400? is
300bps itself some kind of special accelerated-by-encoding? I see 1200
baud was also still sub 3KHz (did any modem protocol go above 3KHz?).
Or maybe I need to ask it this way: did 300 baud modems use a more 1:1
translation of the data-word bits into Hz signal over the modem (giving a
more "natural" translation rate?) But then beyond that speed, does a modem
need to "cache" a few bytes and determine some encoding scheme to then give
modems an apparent speed boost? (is that "kind-of" like USB's 8B/10B?
(not in implementation, but in the general concept that a different
encoding can result in improved data throughput, without actual faster
movement of that data?)
I guess it gets into the "secret sauce" approaches of how vendors figured
out these encoding approaches (v.32bis, etc), and give their product
competitive advantages (but only if you could convince enough ISPs to adopt
your protocol, by buying your modem device).
My daughter made me finally watch Blackberry recently, it's an interesting
telling of that story (of a small business selling their tech to USR, and
also that they tackled a version of encryption)
-Steve
Al has a reader at CHM. They can read tapes too, my 7-track setup is now at System Source.
Paul
> On Sat, 2025-02-15 at 14:52 +0000, Sid Jones via cctalk wrote:
> > IIRC, I have a copy of the Elliot 803 A-103 Algol compiler on a five-
> > hole
> > tape in a drawer somewhere in my untidy office...
> >
> > As used in UCNW Bangor, 1971-1974.
>
> There might be a reader somewhere. If anybody has (or developes) an
> 803B emulator, it would be nice to have the compiler.
>
> Paul Pierce read several IBM 1401 tapes. The Computer History Museum in
> Mountain View, CA has two operating 1401s, and the SimH project has an
> emulator. It's nice to have the Autocoder assembler, FORTRAN II and
> FORTRAN IV compilers, COBOL compiler, ⦠to use. There are students at
> San Jose State University who go to classes in 1401 programming at CHM.
>
> Maybe Paul has a paper tape reader too.
>
>
>
>
https://thisistrue.com/sokol-behind-scenes/
It's probably not overly important how the 6502s got sourced for the
Apple I, but here's a different take. Debate as you see fit, I'm just
the messenger.
Jim
--
Jim Brain
brain(a)jbrain.com
www.jbrain.com
Hey all! So, I've found myself studying up on RS-232 this year for a few
reasons.
I'm mulling over doing an RS232 themed talk at June VCF. Not a super
exciting topic, but I do think that RS232 has an interesting history: In
the SAGE relationship, and as a follow up to (essentially) prior telegraph
communication.
From what I've read, "50 baud" was a kind of an initial goal to beat, since
that's what the top telegraph operators could achieve (in small burst,
probably not all day). And those operators did have to also deal with
things like start/stop "bits". Maybe it wasn't an intentional goal, but
just that it establishes why "50 baud" is generally the lowest we ever see
mentioned (or, if you go slower than that, might as well use the older
tech).
Then 75/110/130 baud to have digital-systems interoperate with classic
mechanical teletypes. Going any faster and those systems jam up or
overheat? These weren't yet called "serial ports", so I'm not sure what a
late 50s system would even call their equipment that facilitate this data
exchange (since I'm not sure what kind of crystal-clock they even had
yet).
Then, was it the SAGE program that demonstrated the idea of doing this kind
of data exchange across copper phone lines? That is, the idea of computers
collaborating not just in a room, but across long distances (miles)? And
doing so by using an audio tone presentation? (they settled on around
3100MHz, which ended up translating to 300 baud? hence, that's basically
why the first digital to digital system data exchange settled on that baud
rate, which was reliable on both 50 and 60Hz power systems, and
meaningfully faster than prior 110 baud - so a good milestone to turn it
into a product, which was the Bell Model 103?).
I couldn't find much details (like a manual) on the Bell 101 equipment
(anyone seen one or have a manual?). But I did find the Bell 103 manual -
the photo of its innards is grainy, so I don't understand how the Bell 103
did 300 baud without a UART (and one of the pinout lines I see did run
power, so not sure if that's-yet RS232 or not; I know RS232 was evolving
right at that same time circa 1962). I've about the 1970ish TR1402
initial DIP UART, with anything prior being an experiment (like a full
board concept by DEC).
I know from 1962, both RS232 and ASCII standards still took maybe another
decade to really gain traction as standards (at least, from what I've
read). Getting the world to comply with any standard always takes a lot of
effort (for a practical reason of everyone still having invested in the
older tooling that was still functional). But it's interesting how those
two standards are still in use (not in their original form, but least the
1967 revisions) - extending from Baudot.and late 1800s-tech on telegraphs.
Does anyone know of any grocery stories using RS232 in the 1960s? I think
barcode scanning was just introduced in that era. I can just imagine a
smart grocery store owner, in the backroom programming their minicomputer
for payroll and inventory management. In FORTRAN and without a CRT?
Actually, in the 60s, I think included software would be negotiated with
the provider of the computer (well, I'm not sure how that differed between
minis and mainframes).
I know early microcomputers used RS232 for keyboards (1974-1976 era). The
IBM PC keyboard is essentially another form of serial.
Well, sorry for the rambling - have other RS232 related questions, but
first wanted to focus on the historical aspects (and see if I'm somewhat on
the right track at least).
-Steve
On Fri, 14 Feb 2025 12:00:07 -0600
cctalk-request(a)classiccmp.org wrote:
> I can't believe people do use it any more without filtering. I've
> used an ad-blocking web browser for some years but I occasionally see
> the real thing when setting up a new machine. Absurd.
It really is astonishing how bad it's gotten - fully the equal of the
early '00s when sites might just spawn a dozen pop-ups and only one of
the major browsers let you block them, only now there's a pile of JS
mining crypto in the background, to boot :/ Been running with NoScript
and an ad-blocker as my standard configuration for many, many years
now, but it's always sobering to get a look at what other people see...
I am about to get a NCR EM-D2 card reader, but I can not find much
documentation on it.
Is there anyone here that has documentation on it? Preferably a maintenance
manual.
A couple of years ago (perhaps in February 2021 if one studies how
they indexed the file in their storage) there was a sale of a maintenance
manual on Ebay according to the below Worthpoint link.
https://www.worthpoint.com/worthopedia/1965-ncr-em-d2-punched-card-reader-3…
Did anyone here buy this manual? I am very interested in a scan of this
manual or possibly to purchase the manual.
/Mattis
