test-drb December 2019

test-drb@ccmp.vtda.org

119 participants
88 discussions

by jnc＠mercury.lcs.mit.edu

> From: Mattis Lind > Thanks Noel for sorting this out. Eh, de nada. But thank you. >> I wonder if the ucode in the two versions is identical? The uROM chip >> numbers should give it, (if they are the same on both versions, albeit >> in different locations on the board), but I have yet to check. Does >> anyone happen to know? OK, so the situation here is pretty complicated. To start with / make things worse, that CPU uses lots of PROMs. Lots and lots and lots and lots of PROMs. For the data paths board (M7260), both major versions appear to contain the same PROMs (going by the DEC part numbers), but the chip location (Exx) numbers are all different. For the control board (M7261), the C, E ('early' version) and F ('late' version) etch revisions each contain mostly the same PROMs, but apparently with slight differences between the sets of PROMs in each (as reflected in different DEC part numbers). For details see: http://gunkies.org/wiki/PDP-11/05#Control_PROMs to which I have just added all the gory details. As to getting the contents of all of them dumped in machine-readable form - oi vey! >> on the earlier version (prints for that version are in the GT40 prints >> online It turns out that I have hard-copy prints for the "C" etch revision of the M7261, which do not yet appear to be online; the GT40 prints have the "E" etch revision. I will scan the pages for that revision of the board, and put them up 'soon'. (I'm not doing the whole print set, it's about 1" thick, and most of them are for other things anyway, like MM11-L memory, etc.) Noel

2 years, 10 months

Font for DEC indicator panels

by jnc＠mercury.lcs.mit.edu

> From: Toby Thain > To get closer I'd need better images of the panels. Hi, I borrowed a DEC inlay from someone (a KA10 CPU bay) and scanned a chunk of it (as much as I could fit into my A4 scanner :-) at 200 dpi: http://ana-3.lcs.mit.edu/~jnc/tech/jpg/KACPUPanel.jpg I have a TC08 inlay, but it's currently being used in my QSIC display (until we can get the RKV11-F/RPV11-D inlay done :-), and I didn't want to yank it out. As far as I can tell, it's the same font on the two of them. > the closest I know of off the top of my head is Akzidenz Grotesk. The Akzidenz Grotesk Medium is indeed very, very close (other than the zero). Do you happen to know if that font available for use in non-commercial settings? Thanks! Noel

3 years, 5 months

Pro 350 Print Set

by robert.jarratt＠ntlworld.com

Manx lists MP-01394-00 as the Field Maintenance Print Set for the DEC Professional 350. I can't find this online and I was wondering if anyone has a scan of it by any chance? Thanks Rob

3 years, 6 months

Motorola EXORciser M6800 System

by osi.superboard＠gmail.com

Since a few days, my EXORciser Development System is finally able to boot from floppy diskettes. Previous attempts have shown that the Motorola EXORciser M68SFDC1 floppy disk board used has a special modified ROM version. This was probably written for an 8-inch drive, in which the Write protect and Direction signal were inverted. For the sake of simplicity, I have used free inverter on the board to invert the signals accordingly. After adjusting the PLL frequency, reads and writes from the card are now error-free. And all without FDC, only clever programming by Motorola software engineers in the early 76? Originally, the EXORdisk system was a dual drive with two 8 "units. This I have replaced with a double drive of two 5.25 inch units. An Epson and a TEAC, which can be jumpered to 360 rpm. Luckily, 2HD floppy disks are easy to R&W. I also got a GOTEK floppy emulator running, which I can boot from. Thanks to Roland Huisman, Bitsaver has some interesting floppy disks that convert to HFE format work perfectly. This format makes the Gotek drive most reliable. Now to my question. The vintage computer forum at http://www.vcfed.org/forum/archive/index.php/t-44638.html mentioned some interesting manuals. Archive.org has some manuals, Bitsaver does not have manuals about the M6800 development system. If someone already owns scanned manuals to the following list M6800 Basic Interpreter Reference Manual M6800 Macro Assembler reference Manual M68SFDU Exordisk 11/111 Disk `Drive Unit Maintenance Manual M6800 Exorciser 11 User's Guide M6800 Exorciser User's Guide MEX68PP1 PROM Programmer Module Supplement M6800 Exorciser User's Guide I would welcome any feedback or questions --THOMAS

4 years

anybody have MOVIE.BYU?

by rdawson16＠hotmail.com

The famous Brigham Young University 3D graphics program, by Dr. Hank Christensen. I am looking for the fortran source, it should be 7 files: DISPLAY SECTION UTILITY TITLE COMPOSE UPDATE MOSAIC Any docs related too. Thanks for letting me beg. Randy

4 years

Discord

by jwest＠classiccmp.org

Greetings folks The past few years I?ve become fairly focused on a particular old 1999/2000 ww2 fps computer game. Of course playing it but I?m also on the development team for the game (EA has given up on it, but we still put out new releases, maps, patches, etc.). As a result of that, I pretty much live on Discord text/audio chat these days. If you send me an email I will eventually see it and may even respond heh. But if you send me anything on Discord I?m going to see it immediately. If any of you are on discord, I am ?Todesengel#9624?. Feel free to add me as a friend and that way you can get me usually immediately. I am not leaving the hobby, nor am I saying not to email me at the usual address. But a lot of you do talk to me semi-frequently and I?m just saying discord will get to me far quicker. In addition, mostly as an exercise to see how to do it, I set up a ClassicCMP discord server. That Discord server is NOT meant to replace this list, nor should it be taken to signal any less commitment on my part to keeping this list running. They are fundamentally different things; Discord is great for real time text chat back and forth. There are also audio and video channels if people want to use that to talk verbally or via video. To get on that server, here is a semi-permanent invite: https://discord.gg/U8Skw5g Joining the server gets you to all the other folks who may join the classiccmp discord, not just me. Of course, that could be zero ? Like I said, I just did it as an exercise, and discord is how some of my family and friends stay in touch. But it is there if peeps want to use it. I?d rather not turn this into a long debate of whether discord is good or bad or anything like that. I?m just saying it?s there, and it?s quicker to get ahold of me that way at times. Best, J

4 years

Lars Hamrén / Computer Automation Museum Project

by aek＠bitsavers.org

anyone know what happened to this? the last sign of the web site was in 2010 https://web.archive.org/web/20100314165117/http://www.sdu.se:80/computer-au… someone just asked about some floppies that I had archived in 2008, and noticed most of the CA stuff on the web has vanished

4 years, 3 months

One of Bay Area's last Fry's Electronics stores closes

by t.gardner＠computer.org

Palo Alto Fry?s closing <https://www.sfgate.com/bayarea/article/Bay-Area-locations-Frys-Electronics-…> . Sad, but not the end of an era ? apparently the loss of lease I remember visiting an early Fry?s (first?) in Sunnyvale (541 Lakeside Dr?, near Oakmead and around the corner from Shugart Associates where I then worked). I marveled at the selection of steaks, diet cokes, resistors, capacitors, ICs, etc. They had partially converted a supermarket into an electronics store but I heard they at first kept the food to keep some cash flow. I think I bought steaks J The engineers and technicians at Shugart more than once ran over there to get breadboard parts.

4 years, 3 months

First Internet message

by c.murray.mccullough＠gmail.com

I?m not familiar with U.S. law but didn?t Xerox ?own? the patent(s) to GUI technology? Again to my knowledge Microsoft and Apple both ?appropriated? and/or ?misapproriated?, depending on your point-of-view, this exact technology! Does commercial-use, read profit, subsume legal rights eventually in the U.S. and I suppose elsewhere in the capitalist world? Given what has happened in the past 45 yrs. or so, and the almost equal value of Microsoft and Apple(determined by the stock exchange), has the marketplace prevailed? Have we the consumer benefited the most or more accurately the 2 richest high-tech, transnational corporations? Happy computing - and best wishes for a prosperous New Year for all. Murray ?

4 years, 3 months

Replacing Electrolytic Capacitors on VAXmate Video Board

by robert.jarratt＠ntlworld.com

I have my VAXmate in pieces at the moment because the PSU has failed. I am still working on finding the fault there, although it seems to be the crowbar circuit that is shutting it down. To work out the problem I am going to buy a DSO (Rigol DS1054Z) as my regular scope is analog and not much use in detecting one-off events. It is an odd fault because there was a definite bad smell after the failure, but I can't find any blown components. Whatever blew up has presumably taken something on the PSU board with it, but I don't know what yet. The PSU shuts down even with none of the other VAXmate boards attached (and using a scratch HDD as a load). Anyway, while I have the machine open, I thought I would look at the video board capacitors too. Before the PSU failed, I noticed a bit of an occasional wobble in the screen image and a narrowing of the image at the top of the screen. I have measured ESR on all the electrolytics. All the larger capacitors seem to have a low ESR compared to the table printed on my ESR meter, some of the small ones (15uF/16V sort of size) have an ESR closer to the values printed on my ESR meter. I don't really want to replace everything if I don't have to, but equally I don't want any kind of failure to ruin an irreplaceable component like the transformer. Should I just re-cap the lot, or just the physically smaller capacitors? Thanks Rob

4 years, 3 months

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test-drb December 2019