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101090 discussions

Help identifying mystery Dataram VAX-11/750 (?) board

by derschjo＠gmail.com

Hi all -- Picked up a board advertised as a "4mb memory board" for a VAX-11/750. It's made by Dataram and I'm unsure of the model number, based on photos of it. I just noticed that rather than being a hex-height board that goes in the memory backplane, it looks like a board that goes in the main CMI backplane. It also appears to have 16mb of ECC memory on it, rather than 4mb. My thought is either (1) it's not actually for an 11/750 (in which case I'm curious what it would go into), or (2) it completely replaces the memory controller and standard memory and gives you 16mb in the 750. (Or it could be that it's something else entirely.) If anyone has any ideas or has a source of information, let me know. I put up a few pictures here: http://yahozna.dyndns.org/scratch/dataram/ Thanks as always, - Josh

5 years, 10 months

Compaq Smart Array 3200 Controller as a SCSI Controller

by cctalk＠gtaylor.tnetconsulting.net

On 7/17/20 7:07 PM, Paul Koning wrote: > Yes, if you define it that way then clearly I agree. The thing is > that in most people's definition, "drive failure" means "the drive > is a door stop". Ya.... I've had too many "but the drive isn't a brick ... how could it be the failure" experiences to use that as my benchmark. Now, if the drive is not doing what it's supposed to do in any (reproducible) manner, I consider it a failure. Well ... almost any reproducible manner. > And in fact, hard read errors are normal. Every drive has a spec for > the probability of that happening, and given the per-sector failure > probability and the sector count, the probability of SOME sector > failing to read when you read the whole drive is nowadays somewhere > around 1. Ya. That's where the reproducibility of any given failure comes into play. -- Grant. . . . unix || die

5 years, 10 months

Small C ver 1.00 source?

by wrcooke＠wrcooke.net

I'm trying to find source files for the very first, original, ver 1.00(?) small C compiler. I have the DDJ issue with the printed source (minus the assembly language runtime libs.) I have found all sorts of derivative works, but I haven't found files of the original version. My old eyes aren't up to typing in 13 pages of scanned copy of printed dot matrix listings. Does anyone know where a downloadable copy of these files can be found? Or have a copy they could send? Thanks, Will "A designer knows he has achieved perfection not when there is nothing left to add, but when there is nothing left to take away." -- Antoine de Saint-Exupery "The names of global variables should start with // " -- https://isocpp.org

5 years, 10 months

interfacing DSI NC 2400 tape reader/punch

by billdegnan＠gmail.com

Is there a trick to archiving tapes to PC using Teraterm from a DSI NC 2400 reader/punch? Or is there a best software for this? From the terminal I can ctrl+Q to cause the reader to initiate a read of a test tape but I can't capture the output of the tape through the modem port of the reader into the serial port of my PC. I tried various things with settings. I was told it uses hardware flow control. The reader is set correctly as far as I can tell. I am using 2400/8/n/1 but I have tried other settings. I get no response from the terminal inbound at all. I am using a USB to serial interface that I know works with an RS232 modem, but it may not work with the reader. If so, I'd like to know if anyone has a similar experience. It may not be straight forward and I have to make a custom cable. I will keep at it, report if I find the answers. Bill

5 years, 10 months

100p Cables

by grumpyx＠gmail.com

I ran across some 50 POS 100 C/L card edge ribbon cables 9.5' in length, AMP 1-583717-9 connectors on each end. It's 2 x 50 pin cables between the connectors. https://drive.google.com/drive/folders/1rjGLewB3J4fDJc5cTRgDwInAVjWz2dxx?us… Any good uses for such a cable? Anyone in need of some?

5 years, 10 months

Dilithium Press (Computer Books)

by healyzh＠avanthar.com

Out of curiosity, does anyone know anything about this publisher? They apparently existed in the late 70?s and early 80?s. They were apparently located in Beaverton, Oregon in the same business park, on Nimbus, where Norvac Electronics was. They obviously published some very strange computer books, including what looks to be a teen romance. I find myself with an embarrassingly nice little collection of the books, that my Dad apparently had. Considering I think he touched a computer twice in his life, they?re something of a mystery. Best title, ?Nailing Jelly to a Tree?, which is apparently a book on Software. The publisher sounds vaguely familiar, and I think I might have one or two other books from them in my collection. Zane

5 years, 10 months

Gotek Floppy Drive Emulators in general and as RX50/RX33 replacements

by bobsmithofd＠gmail.com

Two questions, 1. If anyone is using these devices, which firmware/software do you use in the device and why did you choose it? 2/ Is anyone specifically using one as a replacement or adjunct or and RX50 et al on a Pro, pdp11, uVax, DecMate, or Pro box, and same question set as 1? Yes, i picked up one, and looking at the capabilities, documentation first, and considering reflashing the beast to give more control of formats. TIA bob smith

5 years, 10 months

Microfiche reader spotted in Longmont, CO thrift store

by cruff＠ruffspot.net

If anyone along the northern Colorado Front Range is in need of a microfiche reader, it was reported to me that a Micro Design model 4010 is sitting in the Longmont Community Thrift store. My source didn't notice a price. The condition is unknown, but it appears to be reasonably intact, and a cell phone picture from the front is available if you send me a message.

5 years, 10 months

CDC CYBER 170 Consoles

by ccth6600＠gmail.com

I have been working on CDC CYBER 170 mainframes between 1977 and 1988. In 2002 I wrote an open-source emulator for the CDC 6000 and CYBER series (see my website http://www.control-data.info/). In 2013 I also developed the open-source VHDL firmware emulating the console controller for these systems. The firmware runs on a Xilinx Virtex 6 FPGA on a PCI Express (PCIe) board. The off-the shelf Xilinx board carries a small custom "piggy-back" board with 4 DACs and 4 op-amps to interface to a DD60or CC545 console. This PCIe board was used by Paul Allen's Living Computer Museum (LCM) in Seattle from 2013 onward in a PC running my 6000/CYBER series emulator to drive a real DD60 console. The CC545 has a very similar interface and my emulated controller would work with it too. For many years I have been trying to find one of these vector drawn CC545 consoles to use with my emulator but I haven't been able to find one. Recently I decided to build a clone of it myself. Bitsavers has a hardware manual with schematics: http://www.bitsavers.org/pdf/cdc/cyber/cyber_170/62952600L_CYBER_170_Displa… The CC545 console achieved unusually fast deflection with an electromagnetically deflected CRT. I am trying to understand the tricks they used to get these high speeds. Part of the magic is a dual-yoke which provided gross positioning within 2 microseconds to anywhere on the screen using the first yoke (this is VERY fast) and then painted the character using a second yoke around that base position with 0.1 microsecond per stroke (this is VERY fast too). The two yokes work in an additive manner. The reason there are two yokes is that you need quite low inductivity/impedance to be able to drive the symbol vectors at 0.1 microsecond per vector with up to 24 vectors making up one character. The gross position yoke needs to create a large enough magnetic field to sweep across the entire screen so has a higher inductivity/impedance but the magnetic field has 2 microseconds to stabilise. The older DD60 console used electrostatic deflection which is much faster by its very nature. Traditional CRT oscilloscopes were all electrostatically deflected because of the speed advantage over electromagnetic deflection. The CC545 manual on Bitsavers has a good description of the circuits and schematics, but unfortunately Section 8 with the "Parts Data" has not been scanned. I really would like to know the types of transistors used in the 4 deflection amplifiers as well as the details of the dual-yoke and possibly the CRT data. It would also be very useful to see details of the design of the dual-yoke and possibly the inductivity of each of the coils. This dual-yoke is most unusual and very different from what is used in TVs, CRT monitors and even vector drawn games like Vectrex or early vector drawn Atari arcade games. Could somebody please help? Thanks Tom Hunter

5 years, 10 months

cray unicos cds sold on ebay in 2016

by plamenspam＠afterpeople.com

Any clue who won this auction: https://www.worthpoint.com/worthopedia/cray-research-unicos-operating-syste… ?

5 years, 10 months

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