- cctalk - classiccmp.org

by Douglas Taylor

Hopefully I can find someone who has a manual for this qbus board, if not, does anyone have experience with this board? Summary: It's a dual width qbus board with 1 DLV11-J port, 32KW Boot room, on board LTC circuit and has a 16 pin connector to attach to a front panel. I dumped the prom's and you can see them over on the VCF Forum/DEC page. I used PDP11GUI to probe the I/O space and it looks similar to a MXV11-B boot board, with the addition of a serial port, LTC and front panel control. The board has copyright 1986 so it's not that old. I guess a front panel would have; LED for RUN, LED for DC OK, a switch for HALT, switch for RESTART and possibly a switch to disable LTC. The board has a couple of 4N25 optocouplers and what signals would need isolation? Yes, I would like to use this put together a working qbus PDP11 using either 11/23 or 11/73 CPU, just for fun. Doug

2 years, 1 month

2
2
0 0

Illiac II Library Routine

by Marvin Johnston

A friend of mine passed away about a year ago, and his wife is just getting around to sorting through his many books, papers, etc. The title of the heading title is what caught my attention. My current plan is to scan the 9 page paper and make it available to interested parties. Since me my plan is to bring many of his books/manuals to VCFMW in September. The identification is "A complete NICAP program which does matrix arithmetic." The heading is: University of Illinois Graduate College Department of Computer Science Illiac II Library Routine F1-UOI-MTRZAL-82-NI After I get it scanned, I will submit it Bitsavers and give the original to the Computer History Museum. There may end up being more such papers as his stuff continues to be sorted through. Marvin

2 years, 1 month

4
4
0 0

Re: Experience using an Altair 8800 ("Personal computer" from 70s)

by brianb1224

😀

2 years, 2 months

1
0
0 0

Re: Experience using an Altair 8800 ("Personal computer" from 70s)

by brianb1224

If I had his digital basement I would never come out.

2 years, 2 months

2
1
0 0

Richmond Retro Computer Meetup - Sat. Jun. 15, 2024 - Richmond, VA

by Jeffrey Brace

Richmond Retro Computer Meetup Sat. Jun. 15, 2024 at the Richmond Public Library in Richmond, VA https://www.meetup.com/richmond-retro-computers/events/301122005/?utm_mediu…

2 years, 2 months

1
0
0 0

Re: Experience using an Altair 8800 ("Personal computer" from 70s)

by John

On Mon, 03 Jun 2024 12:00:08 -0500 cctalk-request(a)classiccmp.org wrote: > > It's like John Conway's "game of life," but more prone to cause > > uncontrollable fits of laughter. > > You owe me a new keyboard (and another glass of milk). Even in death, his power remains ;)

2 years, 2 months

1
0
0 0

TinyTapeOut and the Z80

by Martin Bishop

https://www.eenewseurope.com/en/tiny-tapeout-7-readies-open-source-z80-desi… May be of interest both in the context of the Z80 and other unobtanium silicon The lead time is long, ~6 months Martin

2 years, 2 months

1
0
0 0

Re: Experience using an Altair 8800 ("Personal computer" from 70s)

by John Ames

From: CAREY SCHUG <sqrfolkdnc(a)comcast.net> > I used 1620s, and 360/30s, a 360/40, and others as a personal > computer at times, for things like writing a Tim Conway game of life, > keeping track of my vinyl records, etc. It's like John Conway's "game of life," but more prone to cause uncontrollable fits of laughter.

2 years, 2 months

2
1
0 0

Re: C. Gordon Bell, Creator of a Personal Computer Prototype, Dies at 89

by Mark Matlock

In addition to the Goodyear STARAN computer, another tire company Firestone did built some interesting one off systems of unusual design. My first job out of college was with Firestone Central Research. While there, I became friends with William Clayton who was one of three of their research fellows. He was a big proponent of APL and there I was exposed to the MCM/700 (see https://www.softwarepreservation.org/projects/apl/Brochures/MCM700Brochure ) and the IBM 5100 desktop APL computer as well as APL via IBM 360 timeshare. We used APL to simulate the heat flow and rubber curing in very large earth mover tires with finite-element techniques coupled with chemical kinetics. However, Bill Clayton most interesting work was around optimizing formulations from designed experiment data. He built an analog computer that used static card readers that provided contacts to feedback resistors to simultaneous compute the output of 16 second order polynomial equations with cross terms for 8 independent variables. Each of these 16 polynomials had 54 static coefficients that were determined from second order statistical regressions of data from designed experiments. One equation for example might be tensile strength of a rubber compounded with various amounts of sulfur, carbon black, oil, accelerators, etc. Then another equation might represent wear resistance measured from the same combination of compounding ingredients. The 16 equations had upper and lower limits of acceptable values for tensile strength, wear, etc. The analog computer would then begin an exhaustive grid search of the 8 independent variables to find a combination of the 8 ingredients that met all 16 of the desired output traits. When a solution was found the independent variable value voltages were read by an A/D controlled by a PDP-8 and then printed on a console. Thus the system was actually a hybrid computer part analog and part digital. I was told that doing the 8 factor grid search in Fortran on an IBM 360/168 would have taken 1300 hours but this hybrid system did it in 5 minutes, Only three of these systems were ever built, two of which were used outside of Firestone (one by the Air Force). U.S. Patent 3,560,725 from 1968 provides some background as it covered an early version of the later more highly developed system. Mark > From: Paul Koning <paulkoning(a)comcast.net> > Subject: [cctalk] Re: C. Gordon Bell, Creator of a Personal Computer Prototype, Dies at 89 > Date: May 23, 2024 at 6:58:06 PM CDT > To: "cctalk(a)classiccmp.org" <cctalk(a)classiccmp.org> > Cc: Kevin Anderson <kevin_anderson_dbq(a)yahoo.com> > Reply-To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk(a)classiccmp.org> > > > I have a vague memory of visiting the Computer Museum when it was still at DEC, in the Marlboro building (MRO-n). About the only item I recall is a Goodyear STARAN computer (or piece of one). I found it rather surprising to have see a computer made by a tire company. I learned years later that the STARAN is a very unusual architecture, sometimes called a one-bit machine. More precisely, I think it's a derivative of William Shooman's "Orthogonal Computer" vector computer architecture, which was for a while sold by Sanders Associates where he worked. > > paul

2 years, 2 months

1
0
0 0

Re: interlace [was: NTSC TV demodulator ]

by CAREY SCHUG

This may have been covered before, VERY early in this tread. I think I tried a game on a flatscreen, and had issues. I don't know if it applies to the radio shack Color Computer, the interest of the original poster. many games and entry pcs with old style tv analog format, don't interlace, and tube TVs nearly all (except maybe a few late model high end ones?) are fine with that, but I seem to recall that most or all digital/flat screen can't deal with non-interlace. <pre>--Carey</pre>

2 years, 2 months

10
17
0 0

2026

2025

2024

2023

2022

cctalk