test-drb September 2019

test-drb@ccmp.vtda.org

131 participants
100 discussions

by aperry＠snowmoose.com

Can anyone here provide a pointer to info on testing vintage power supplies? Search results on the web may eventually lead to the kind of info that I am looking for, but I have to get through too many pages of modern PC power supplies first. Specifically, I will be testing the power supplies in my Sun 3/260, which has 24V, 12V and 5V. I am wondering things like what is suitable loads and do I need to put a load on all three or can I test them one at a time and what I haven't thought of with regards to testing them. alan

5 years

Searching cctalk/cctech

by aperry＠snowmoose.com

Is there a way to search all of cctalk and cctech? I found the archives, but that is split all of the postings in a given month. alan

5 years

Shugart-Interface 8" Floppy Diskette Drive Configurability

by nf6x＠nf6x.net

I've been contemplating a floppy diskette drive emulator with features to make it fit better into systems using 50-pin Shugart style floppy drive interfaces vs. the other emulators already on the market. Studying manuals for various 8" floppy diskette drives, I see that they generally provided a great deal of configurability. There are the myriad of jumper-selectable options which change drive behavior for compatibility with various computers. Then there are features like FM data separators which are present on some, but not all, drives. And then there are many documented "cut this trace, then bodge wire this signal to pin X of the edge connector" options for special purposes such as individual drive motor controls, simultaneous monitoring of all four drive ready signals, etc. Since fully supporting all of the options I've seen documented would have real hardware cost and add complexity to the design, I'm wondering just how much of that configurability is really necessary. Which non-default options are really needed for system still in use and/or in the hands of collectors? Which were only ever provided for some obscure industrial system manufacturer, with no surviving systems in existence? Which were included just in case somebody might need them, but were never used in practice? I'd appreciate it if anybody can provide insight into this, such as examples of systems which required non-omnipresent and/or non-default configuration options. -- Mark J. Blair, NF6X <nf6x at nf6x.net> http://www.nf6x.net/

5 years

Data General/Rolm milspec systems

by technoid6502＠gmail.com

Message: 4 Date: Thu, 5 Sep 2019 10:03:54 -0400 From: "Craig M." <cmook1968 at gmail.com> To: cctalk at classiccmp.org Subject: ROLM - Dat general 1602 - AN/UYK-19 computers. Message-ID: < CAD1aQJ5FnQDS7i+iLeh-+zBSBrzaqV9-f61Q76XgEbz=fSN+nw at mail.gmail.com> Content-Type: text/plain; charset="UTF-8" Good Morning, Have you ever come across a document called the "Rolm I/O Designers Guide?" I am working with some developers trying to figure out the data words and how they work on a Navy AN/UYK-19 computer. I have some sticktime on the Eclipse machines. In going to boot camp getting my MV4000/DC I ran into some interesting characters. One was with DG on military sales, was visiting Groton? or another base where a test was being conducted. The computer was suspended on wires in a hangar and, while running, was subjected to simultaneous blows from heavy pendulums on either side. The noise was teriffic and my friend asked the same question, why on earth, to which the cryptic reply was two words: Depth Charges. Probably your USAF machine, corn field kept though it was, was designed for service in another kind of silo, the missile kind. Those would be projected to survive near-direct hits from megaton thermonuclear weapons. Not to mention that no air force property is immune from attack by all sorts of ordinance, nuclear or otherwise. Best, Jeff Another note, saw an old query on the "Rolm Computers: 1602, 1602A, 1602B, 1666, MSExx (was Data General Nova Star Trek)" thread about breaking down the military system designations. This website may help if you never got an earlier answer: https://dsm.forecastinternational.com/wordpress/2015/05/27/whats-in-a-name-… Thank you! Craig Mook

5 years

keyboard list

by sales＠elecplus.com

This is the next list of keyboards I can bring in. Anybody want some of this? 2 IBM 6052141 IBM 1391401 missing some keycaps Apple M3501 nice ,no pluggable connect cable WYSE PCE,p/n 900840-01 Din-5 connector Data Desk Int,new/unused Din-5 Datatech SBK-100 Cadmus 00185-00 (dark grey) no plug-in connect cable 2 Chicony KB-5311 very nice Din5 Commodore KPR-E9447 unused Din 5 Honeywell 101WN unused Din-5 Keytronic KB101 Plus Din-5 Mitsumi KPQ-EA9YC looks good Din-5 Mitsumi NPQ-E99ZC-13 Din-5 HP C14058 If so, please send price offer for what you want. Shipping will be extra. Yes, I will ship internationally. Cindy Croxton Electronics Plus 1613 Water Street Kerrville, TX 78028 830-370-3239 cell sales at elecplus.com --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

5 years

Seeking enlightenment regarding Bus Adapter Purges on Unibus VAXen (and their ilk)

by derschjo＠gmail.com

Hi all -- Been working on an MSCP implementation for Joerg Hoppe's Unibone project, and it's working well on PDP-11 systems; less well as of late on the VAX. I've been looking to tidy up a few dark corners in the MSCP spec and one thing that's left is bus adapter purges -- I have a pretty good grasp of Unibus mechanics these days but I'm not quite understanding the reasoning behind this. Here's what the Storage System Unibus Port Description (AA-L621A-TK) document says: "To support such higher-level protocol functions as transfer restarts, compares, etc., the host memory interface must allow repeated access to a given host memory location for both reads and writes. On purely Unibus systems such as 11/44, this requirement is trivially met with no participation by the host CPU. On systems with bus adapters such as the 11/780, the repeated access requirement means that the relevant adapter channel may have to be purged, requiring the active cooperation of the host CPU. The port signals its desire for an adapter channel purge by interrupting the host. The host writes zeroes to the SA register to indicate purge completion." This is also discussed, from the bus adapter point of view, in the technical documentation for the bus adapter itself. (See http://www.vaxhaven.com/images/2/29/EK-DW780-TD-001.pdf) It hasn't been particularly enlightening to me, but I will admit to not having read every page of this and the DW780 doc -- maybe I missed something :). I understand the mechanism here; in essence it's: 1) MSCP controller decides a purge is necessary after a DMA transfer and requests one by setting a value in a reserved slot in the communications area 2) Host system (MSCP driver) sees the special value, and issues a purge command to the bus adapter. 3) Host system then clears the value in the communications area 4) MSCP controller continues on its merry way. What I do not understand is (a) why such purges are necessary, and (b) how the MSCP controller knows when one should occur. The Port Description doc hints that it has to do with repeated access to a given area of memory. The DW780 documentation hints that it needs to happen after *any* block transfer. (See pg. 2-58 of the document linked above.) Anyone have any experience with this? Thanks! Josh

5 years

ROLM - Dat general 1602 - AN/UYK-19 computers.

by cmook1968＠gmail.com

Good Morning, Have you ever come across a document called the "Rolm I/O Designers Guide?" I am working with some developers trying to figure out the data words and how they work on a Navy AN/UYK-19 computer. Another note, saw an old query on the "Rolm Computers: 1602, 1602A, 1602B, 1666, MSExx (was Data General Nova Star Trek)" thread about breaking down the military system designations. This website may help if you never got an earlier answer: https://dsm.forecastinternational.com/wordpress/2015/05/27/whats-in-a-name-… Thank you! Craig Mook

5 years

A fun patent to wrap your head around

by aek＠bitsavers.org

5287534 "Correcting Crossover Distortion Produced When Analog Signal Thresholds Are Used To Remove Noise From Signal" It describes the DEC CXM04 board for the DS550 communications server, which inserts itself between an IBM establishment controller and a control unit (coax) terminal so the CUT can pretend it's a serial terminal to VAXen without dropping the polled connection to the IBM mainframe. weird..

5 years

Wanted: ATV Research Pixie-Verter

by wh.sudbrink＠verizon.net

Hi, For historical reasons (I'm starting to plan my VCF East 2020 exhibit) I'd like to get real ATV Research PXV-2A Pixie-Verter. I know that there were a lot of other RF modulators out there (I have a SUP "R" MOD II (that I might trade)) but I want this one in particular. Various S-100 boards and other vintage computer hardware available for trade or cash if necessary. Thanks, Bill Sudbrink --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

5 years

pdp11/34s FTGH in Dublin Ireland

by ronan.scaife＠dcu.ie

Dear All (mainly UK and Ireland), We have a "lo-boy" DEC cabinet containing 2x pdp11/34a in half height boxes, and 2x RL02 drives. It is available for free to be collected in north Dublin, 5 miles from Dublin port. It is also about to be scrapped, so urgent action is required. Please contact ronan.scaife at dcu.ie. Best Wishes, -- -- ?This Email, and any files transmitted with it, are confidential, and are intended solely for use by the addressee. Any unauthorised dissemination, distribution or copying of this message and of any attachments is strictly prohibited. If you have received this email in error, please notify the sender and delete the message. Any views or opinions presented in this email are solely those of the author and cannot be relied upon as being those of Dublin City University. Email communications such as this cannot be guaranteed to be virus-free, timely, secure or error-free, and we do not accept liability for any such matters or their consequences. Please consider the environment before printing this Email.? ==== Dr. Ronan Scaife =============== ronan.scaife at dcu.ie ========== School of Elec Eng, Dublin City University, Dublin 9, IRELAND. http://www.eeng.dcu.ie/~scaifer/ phone (office): +353-1-700-5434 fax: +353-1-700-5508 ==================================================================== -- * *S?anadh R?omhphoist/Email Disclaimer* *T? an r?omhphost seo agus aon chomhad a sheoltar leis faoi r?n agus is lena ?s?id ag an seola? agus sin amh?in ?. Is f?idir tuilleadh a l?amh anseo.? <https://sites.google.com/view/seanadh-riomhphoist>* *This e-mail and any files transmitted with it are confidential and are intended solely for use by the addressee. Read more here. <https://sites.google.com/view/dcu-email-disclaimer>* * -- <https://www.facebook.com/DCU/> <https://twitter.com/DublinCityUni> <https://www.linkedin.com/company/dublin-city-university> <https://www.instagram.com/dublincityuniversity/?hl=en> <https://www.youtube.com/user/DublinCityUniversity>

5 years

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test-drb September 2019