- cctalk - classiccmp.org

by Andrew B

I have an AT&T branded SCSI enclosure. Two half-height bays with the drives held vertically (on their sides), with a door that opens to expose one for a tape drive, activity lights labeled hard drive and tape, CN50 connectors, the AT&T beige and brown color scheme I associate with 3B's and 6300 PCs. No model number. Anyone have any idea what this was made for?

12 months

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ASR-33 Help and Parts Needed - corrected message

by Mike Katz

I was given an ASR-33 complete with stand, reader & punch. This ASR-33 has been modified for RS-232 though a blue perfboard mounted in the connection enclosure (under the cover place where the dialer would be on the right side). It has a DB25 ribbon cable coming off of this board. The perfboard does not have a label on it that I can find. The ASR-33 also has a 3 x 5 conductor rectangular connector coming out of the rear of the unit with 6 female contacts installed. I was able to connect the ARS-33 to a VT-330+ at 110B 8-N-2 and send and receive on the teletype. The punch seems to work as well. The reader will "chatter" then the reader is put in the start position and the tape out sensor is pressed but the sprocket does not advance and the reader pins to not move. Questions: 1. Why the reader is not advancing and the pins are not activating? Could this be a read enable contact not being in the active position? 2. What are the pin outs of the RS-232 DB-25. Other than TX, RX and GND 3. What are the pin outs of the 3 x 5 rectangular connector. I think this is the current loop and other control signals. Does any one of the items below for sale or have a 3D model I can print: 1. Roll Paper spindle (the spindle that the roll paper spins on) 2. Paper Tape Punch Spindle (the spindle that the paper tape spins on) 3. Paper Tape Chad feed tube 4. Paper Tape Chad Box I will be connecting this to either a PiDP-8/I or a PDP-8/E for now and eventually a PDP-8/L Thank you, Mike

12 months

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TRS-80 BASIC oddity

by Bill Gunshannon

I am going to assume there are other TRS-80 people hanging out here and go ahead and ask this: Has anyone here used the DEFUSRx command? I tried to use it for something I am working on and it didn't work. So, I copied the example program from page 115 of the Model III Disk System Owner's Manual and, guess what, it didn't work either. 150 DEFUSR1 = &H7D00 returns a Syntax Error 150 DEFUSR1 = 32000 works fine. Anybody else ever run into this? I can't believe something as blatant as that could have gone on for all those years. bill

1 year

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USDC Unibus SCSI Controller

by emanuel stiebler

It is few years that anybody asks, so here it is again: ANYBODY has any manuals for it? On Discord, we have some discussions, I found some of them in my boxes, but nobody has documentation, and no success to get them working. Any chance?

1 year

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IBM 5100 side scroller (PALM processor)

by Steve Lewis

I've written a "side scroller" program using the IBM 5100's native PALM instruction set. I talked about the 5100 in 2023, and for 2025 I wanted to present something special for its 50th anniversary. I kept getting sidetracked with other projects over the year. But thanks to the IBM 5100 emulator now in MAME, that helped a lot in debugging the program more efficiently. There is much I still don't fully understand about PALM, so I probably do this in the most efficient way, but it does work well. I'm also still working towards restoring a POLY-88 (8080 based system, similar to SOL-20 as far as being S-100 based). Someday I'd like to attempt a similar side-scroller on that platform, to see how the performance compares and if a micro that early could handle it (at 1.8MHz and will need to find 16KB of working RAM- one thing about the IBM 5100, it feels fairly rock solid after 50 years). Unless anyone already has a working 8080-based system and wants to take a stab at this? I'll talk more about the design approach (and use of PALM instruction set) after VCF next month. Here is the YouTube video preview of this scroller in action on real hardware: https://www.youtube.com/watch?v=sRAxKGkXC1I And the Rumble version in case anyone has issues with YT: https://rumble.com/v6tu80h-ibm-5100-vertical-side-scroller-hardware-demonst… If anyone has a 5100 with the "expansion feature" and async card, we're always interested in trying to get old system "online" (through WiModem type devices), or a non-working 5100 is always good for spare parts on the ones that do still work. But one "fabled accessory" of the 5100 is it's carrying case -- which surprisingly was the cheapest item on its price sheet (at $150 new). I've only seen one of these once (in Florida), so they do exist. Or tapes (even later 3M QIC DC6120 are compatible). Cheers, Steve

1 year

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Board repairs?

by Peter Ekstrom

Was there someone on this list who can help repair boards, like the RQDX3s I broke in my H9278? I don't know if it would be too costly, but if not I'd like to restore them to working condition. -Peter

1 year

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Problems with an RQDX3 in an 11/23.

by Peter Ekstrom

Hello to the group, I have been banging my head against a PDP-11/23 where I have an RQDX3 I'm trying to get to work. Actually, I have two RQDX3's but only one at a time. It is configured to the factory CSR, 172150, and it has the latest microcode on it. When I run the XXDP ZRQCH0 formatter I get the following: RQDX3 Disk Formatter Utility UNIT IS Formattable Winchester (RDnn) or Floppy (RX33) Drives RSTRT ADR 145702 DR>STA CHANGE HW (L) ? Y # UNITS (D) ? 1 UNIT 0 Enter controller IP Address (O) 172150 ? What unit do you want to format [0-255] (D) 0 ? Would you like to revector a single LBN only [Y/N] (L) N ? Do you want to use the "AUTOFORMAT" Mode [Y/N] (L) Y ? N ZRQC SYS FTL ERR 00006 ON UNIT 00 TST 001 SUB 000 PC: 105742 Fatal Controller Error During Initialization. ZRQC SYS FTL ERR 00006 ON UNIT 00 TST 001 SUB 002 PC: 105742 Fatal Controller Error During Initialization. ZRQC EOP 1 2 TOTAL ERRS DR> I have been booting XXDP and also RT11 over an emulator TU58. And I have a BDV11 so it has an LTC. I did try downgrading the microcode on the RQDX3 to the previous version, 3. It was 4. But no luck. Am I missing something? This should work with an M8186 CPU board, right? Anyone have any ideas? I haven't yet, but I plan to pop one of these RQDX3s in my 11/23+ and see if it works there. -Peter

1 year

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Re: IBM 5155

by Phill Kennedy

Bill, Please update your email on QRZ.com to a working email address. Thanks Phill, a fellow ham.

1 year

2
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IBM 5155

by Bill Gunshannon

I just managed to score a 5155. Well, soon, it is waiting for me to pick it up at the University where I used to work. It looks to be in really good shape and has been in storage for probably two decades or more. A couple quick question for anyone familiar with this system. Is it likely there is one of those little batteries on it that would now be dead and need replacing before I try to use it? And, also, would this have a floppy controller on it that was capable of reading and writing disks from systems like the TRS-80 with an SD boot track? Inquiring minds want to know. :-) bill

1 year

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Comstar Computer Systems System 4 Intel 4004 based Industrial Computer

by Christian Liendo

Back in Nov of 2023 Ed Sharpe asked the following: “Was there ever a COMPUTER using a 4004 that you could really do something or did that finally arrive with the 8008” https://classiccmp.org/mailman3/hyperkitty/list/cctalk@classiccmp.org/messa… I hope to answer that question, or at least spark a discussion. For a number of years now I have been researching this computer called a Comstar System 4 which is based on the Intel 4004. The Comstar Corporation of Minneapolis was a developer of microcomputer control and automation systems and in 1972 released the System 4 microcomputer. Comstar built a general purpose capable computer that could be programmed to do a multitude of tasks but their market focus was industrial automation. Comstar was eventually bought by Warner & Swasey in 1974 to integrate their computers into the Warner & Swasey product line. Warner & Swasey was a huge manufacturer of industrial machines. So they bought Comstar to be their Computer division. In fact it was called " Warner & Swasey Comstar Microcomputer Electronic Products" Warner and Swasey also licensed the Micral N to do the same and we call the Micral N a computer. The Micral N was designed for process control, but we know of it as a computer. Now before anyone argues about if this is a computer or not, I will state the following. It was called a Microcomputer in the ACM titled "Development of a portable compiler for industrial microcomputer systems " It was called a Microcomputer in Electronics Magazine July 11th 1974 It was listed as a Microcomputer in "Auerbach Guide to Minicomputers" April 1976 & Winter 1976 - 1977 It was listed as a Microcomputer in Datamation Magazine Dec 1974 It was called a Microcomputer in "A MICROCOMPUTER BASED SUBSTATION CONTROL SYSTEM" The University of Oklahoma, Ph.D., 1975 Engineering, electronics and electrical Page 90 It was listed as a Microcomputer in the Intel MCS 4 User Manual Feb 1973 page 171 It was listed as a Microcomputer in Electronics Magazine Jan 1973, they promote the 4004 and 8008 and use the System 4 as an example. The reality is this existed, was 4004 based and there were discussions about it in the media at the time. Anyway I wanted to see if there was more interest in researching this computer. I listed a number of articles and references below that either discuss Comstar, The Warner Swasey Computer Division, the “System 4” or “Star 4” Computer. All the Manuals and schematics I was able to upload to archive.org https://archive.org/search?query=subject%3A%22Comstar+Computer+Systems%22 Computer History Museum's Archive of the Manual https://www.computerhistory.org/collections/catalog/102686568 Pictures of the items I have collected so far https://imgur.com/a/Oyts3A9 The website "Internet Scripophily Museum of Computing" has a page on the history of The Warner & Swasey Company. It's a decent timeline of the company http://ismoc.blogspot.com/2017/06/the-warner-swasey-company.html "Development of a portable compiler for industrial microcomputer systems" by LEROY H. ANDERSON The Warner & Swasey Company, it discusses the system and has images on the unit. https://www.computer.org/csdl/pds/api/csdl/proceedings/download-article/12O… In the ACM's archives "Development of a portable compiler for industrial microcomputer systems" by LEROY H. ANDERSON The Warner & Swasey Company, it discusses the system and has images on the unit. https://www.computer.org/csdl/pds/api/csdl/proceedings/download-article/12O… Electronics Magazine July 11th 1974 Article: Industrial Automatic control proliferates, they are mentioned on page 84 & 85 https://www.worldradiohistory.com/Archive-Electronics/70s/74/Electronics-19… There is a mention about the compiler in the IEEE on Page 25 under Compiler Programmer https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=6368812 Computer Design Magazine Nov 1975 Page 129 they talk about the compiler. https://archive.org/details/bitsavers_ComputerDe_90611286/page/128/mode/2up The Intel MCS 4 User Manual Feb 1973 page 171 and in Electronics Magazine Jan 1973, they promote the 4004 and 8008 and use the System 4 as an example. http://www.bitsavers.org/components/intel/MCS4/MCS-4_UsersManual_Feb73.pdf https://www.worldradiohistory.com/Archive-Electronics/70s/73/Electronics-19… There are a number of sources that list the computer as a "microcomputer" and provide specs showing it being 4004 based. Datamation Magazine Page 97 & 101 http://www.bitsavers.org/magazines/Datamation/197412.pdf In "Auerbach Guide to Minicomputers" April 1976, the computer is mentioned on page 54 and page 70. http://www.bitsavers.org/pdf/auerbach/Auerbach_Guide_to_Minicomputers_Apr76… In "Auerbach Guide to Minicomputers" Winter 1976 - 1977, the computer is mentioned on page 32 http://www.bitsavers.org/pdf/auerbach/Auerbach_Guide_to_Minicomputers_1976-…

1 year

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