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Burroughs DCALGOL vs tapes [from dead computer language thread]

by paul.kimpel＠digm.com

Yes, DCALGOL is still around and actively used. It is a superset of the standard Extended ALGOL, and originally exposed some special APIs and data types for talking to the Datacom Processor front-end. Those APIs are still used, although the "front end" is now TCP/IP. The language has since been extended with numerous other APIs for use primarily by system-programmer types. There is also a DMALGOL compiler primarily used internally with the DBMS, DMSII. All three ALGOL variants have been compiled from the same source code since sometime in the '70s. DCALGOL would have been no different than ALGOL for dealing with tapes, and I'm surprised you found it harder to do with the MCP than with OS/360 EXCP I/O. Depending on the block and tape label formats, you may have had to do your own deblocking, and possibly read the tape as unlabeled, but the MCP I/O Logical I/O subsystem was quite rich even in 1975. You had to understand how the file attribute settings worked when dealing with non-native tape formats, however -- I've seen that trip a lot of people up. As an alternative, a variant of Logical I/O called Direct I/O was available, which is user-mode asynchronous I/O that reads and writes raw blocks. It's basically a thin wrapper around the MCP's internal Physical I/O mechanism. I know this is water long over the dam, but I'd be interested in hearing what kinds of issues you encountered, and if possible, a reference to the DEC formats you were trying to read.

1 month, 2 weeks

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Re: What constitutes a dead computer language

by Mark Kahrs

As a fan of BCPL (from the Alto), I only wish it was better documented. For example, Tripos has next to no documentation on it including how to compile and load it. Documentation on the runtimes is also lacking (and that's where the rubber meets the road). Unfortunately, the Alto changes were not picked up so it remains an isolated branch (and *dead* by the definitions put forward).

1 month, 2 weeks

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m4 model 9914 tape drive and 800dpi 9track tapes

by Bill Degnan

I have found that a modernish Dell PC (win 7 era) when attached to a m4 9914 tape drive has issues when attempting to read 800dpi 9track tapes. I/O errors that seem to be centered around variable block size microcode of the modern scsi controller (?) I've spent a number of hours on it and I could not even pull raw data off an 800dpi tape. 1600 no problem. works fine. is there a tweener box or scsi controller that will work in this situation? what do other people do? Bill

1 month, 2 weeks

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Re: What constitutes a dead computer language

by Paul McJones

On 6/20/2026, ben <bfranchuk(a)jetnet.ab.ca> wrote: > PL/1 and C are the only two high level languages a operating system is > written in, that I can think of that are well documented, and easily > found on the WEB. Additional examples: Pilot (the embedded operating system for the Xerox Star office automation system) was written in Xerox's proprietary Mesa language. History and documentation of Mesa (and some Pilot documentation and early source code) are available here: https://softwarepreservation.computerhistory.org/mesa/ Taos, the operating system for the DEC Systems Research Center Firefly multiprocessor workstation, was written in Modula-2+, which added threads, garbage collection, and runtime type dispatch to Modula-2. History and documentation of Modula-2+ (and Taos) are available here: https://softwarepreservation.computerhistory.org/modula2+/ SPIN, an extensible operating system written at the University of Washington, was written in Modula-3 (with small extensions). History and documentation for Modula-3 are available here: https://softwarepreservation.computerhistory.org/modula3/ and information on SPIN is available here: https://softwarepreservation.computerhistory.org/modula3/#SPIN_M3 .

1 month, 2 weeks

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HP 50Meg disk pack HP13394A

by steve shumaker

Anyone here have an interest or need for a HP13394A removable disk pack? I stumbled across it in a garage cabinet at an estate sale. According to google, it was used in a HP7920 disk drive system with early HP mini processors. Before I post it on THAT website, figured I'd check to see if anyone here could use it. Unit seems in fairly good shape - at least physically. Please respond off-list if interested. Steve Shumaker

1 month, 2 weeks

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UNCOL why it failed

by ben

UNCOL failed because of many reasons, none that I know of. I put the blame on hardware design,throw some logic and memory together CHEAP,QUICK and DIRTY and call it a computer if you can sell one. Call it a computer standard if it for a PHD. Today's memory is loosely based on 8 bit byte addressing, yet there is no Mathematical abstract model to base the computing side of the picture. What are the problems that need to be solved? What are the real world hardware problems like I/O? Are things defined recursivity, in that a simple version, can expand to a complex, and really complex version. Register addressing,base register addressing, array, base register addressing ... Algol 9000. UNCOL is from the era, that it was thought lower cost hardware as gates and memory it would possible have general purpose computer of 32K words or more. 36 bits or bigger word length for single precision floating point. A character set of LATIN upper and lower case letters,and a limited ALGOL 60 character set, like '10' and 'BEGIN' keys.

1 month, 2 weeks

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Looking for RLV12 card (DEC M8061)

by Charles Morris

The RLV12 (RL02 drive controller) in my PDP-11/23+ has decided to quit working when it gets hot in the room. RT-11 won't boot, with an ERR 15 Controller Error. The defect may have become permanent, will have to check in the morning when everything's cool. The drives themselves are not indicating any faults, and both of them exhibit the same behavior on boot. Trying to rig up an emulator (or boot XXDP from the Teac 3.5" floppy) introduces a whole new set of hair-pullers. Since the RLV12 is so complex, I am tempted just to replace it, if one can be had... so does anyone have one they don't need? :) thanks Charles

1 month, 2 weeks

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Re: What constitutes a dead computer language

by Craig Ruff

Anyone do any real work with either the Icon or Unicon language family? I recall fondly sending off for a 1/2" tape with an early Icon distribution from the University of Arizona. I played around with it personally, but never got to use either professionally.

1 month, 3 weeks

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Planar ELT320 Schematics?

by Robert Armstrong

Darn - my beloved Planar ELT320 terminal has died. I was just sitting there using it and suddenly the screen went blank. The keyboard still works and the power LED lights, so not a simply power supply failure. Does anybody have a schematic or service manual for these guys? It's one of my favorite terminals - not only does it have a beautiful orange/amber EL display, but it's also way smaller and lighter than any VTxxx terminal of the era. Thanks Bob

1 month, 3 weeks

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HP 2116 parts needed.

by Mattis Lind

Hello! Last year I rescued a HP 2116B that was going to be scrapped. It has been in storage for quite many years but now the storage building was going to be demolished and a quite urgent rescue operation took place. The machine is now sitting and waiting to be restored to operational condition. When examining the machine it was quickly discovered that it was lacking a few boards. Notably the Memory Module Decoder board which goes into slot 2 and the Power fail board in slot 1 were missing. When I pulled out the card cage to examine the PSU it turned out that also the two regulator modules for the PSU were missing. Since I received the machine I have been able to find a Power Fail board on Ebay, but three boards are still missing: Memory Module Decoder (02116-6274 or 02116-6300) Logic Supply Regulator (02116-6014) Memory Supply Regulator (02116-6015 or 02116-63214) Is there anyone here on the list that happens to have these spare boards or a HP 2116 that is beyond repair? I have been thinking of replicating these boards but it would be nice to find the original and spend the time on something else than tedious replicating work. Reading a 12 year old cctalk thread I saw that Tim Riker had an HP 2116 in not so good condition once upon a time. I wonder if there is anything left from that one? /Mattis

1 month, 3 weeks

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