I saw an email posted to the predecessor mail list asking if anyone had a picture of an IBM 4506 terminal. I was looking through the September 1973 issue Modern Data and saw an article on page 70 about the New York Times’s indexing efforts. It said that they were using IBM 4506 terminals and it has a picture of a large workroom (identified as “The Times index room”) with a bunch of terminals which I assume must be 4506’s (although the caption does not explicitly state that). The magazine is available on BitSavers. Look for the issue with file name Modern_Data_1973_07.pdf.
Tommy Chang
Did any classic computers have a subroutine call as (S++)=PC, PC=(EFA)
as well as the standard call (--S)=PC,PC=(EFA) ?
One could have a virtual stack machine, using helper functions without
having to deal with return addresses on the stack.
Ben.
On Tue, 18 Feb 2025 12:00:10 -0600
cctalk-request(a)classiccmp.org wrote:
> On the more than "one stack pointer" in the subject, it was a bit
> arbitrary on the PDP-11 (or VAX) as the pre/post indexed indirect
> addressing made every register a stack pointer. But this is where I
> get hazy between DEC and 68K, and I did a lot more 68K. I'm pretty
> sure you could do a move.l PC, An and you could certainly do an
> indirect jmp (An), so effectively you could have multiple call stacks
> if you wanted.
Almost, kinda-sorta. The JSR and RTS instructions are hard-wired to use
R6/SP, and there's nothing you can do about that. You *can* implement a
return off another "stack" by doing e.g. MOV @(Rn)+, PC as long as you
save the return address by hand, first - but this affects the flags,
unlike JSR/RTS.
> On 15 Feb 2025 18:41:21 -0800,Van Snyder <van.snyder(a)sbcglobal.net <mailto:van.snyder@sbcglobal.net>> wrote:
>
> Harry Husky, the G15 designer, was one of the computer design pioneers.
> He became a professor (maybe adjunct) at UC Berkeley.
As far as I know, Huskey was a regular professor. Two of his Ph.D. students went on to win the ACM Turing Award: Niklaus Wirth and Butler Lampson:
https://mathgenealogy.org/id.php?id=10185
Huskey went on to found the Computer Science department at U.C. Santa Cruz.
> On 16 Feb 2025 18:00:35 -0700,ben <bfranchuk(a)jetnet.ab.ca <mailto:bfranchuk@jetnet.ab.ca>> wrote:
>
> I have trouble understanding the fine points of accessing a local
> variable in Algol with a display. Books tend to spend more time
> on the evils of a dangling else, and gloss over the run time action of
> a display.
> Have a good example or reference book I can find free on line.
The original book on that subject is ALGOL 60 Implementation by B. Randell and L. J. Russell. It’s available here with permission from the copyright holder:
https://www.softwarepreservation.org/projects/ALGOL/algol60impl/#ALGOL_60_I…
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
