test-drb November 2010

test-drb@ccmp.vtda.org

162 participants
241 discussions

by tshoppa＠wmata.com

De writes: >> I am looking for info on a Gandalf LDS120 modem, specifically the >> serial port pinout. > In the division of irrelevant to the original question, I thought these > things were line drivers, not modems. I always thought they got lumped into "short haul 4-wire modems". They do have "DCD" lights on the front. I seem to recall that it's just a light and doesn't actually assert any RS-232 pins. But they could just be differential line drivers probably with isolation. 20+ years ago I'm sure I looked inside to see what's in there but I can't recall. I always thought they did some simplistic and almost certainly not Bell-standard FSK or PSK but that was just my impression, no actual evidence to back that up. Did the 4-wire screws on the back have labels of "+" and "-"? That would be a point in favor of them being line drivers and not modems (although some simple modems were in fact phase-sensitive). We used them between serial concentrators on different floors or between serial concentrators between nearby buildings. I note that there's no Gandalf directory at bitsavers. Gandalf certainly has a unique heritage not really being a "computer" company in the usual sense but for so many of us it was the gateway from terminal to the computer or between computers. I get the impression they were far more common at large academic institutions than at any commercial site. Tim.

13 years, 10 months

Old terms...

by bqt＠softjar.se

On 11/09/10 10:44, Roger Holmes<roger.holmes at microspot.co.uk> wrote: >> > From: Johnny Billquist<bqt at softjar.se> >> > >> > Gah. I have no idea what PPU mean, nor PP. > You're probably just not old enough. That is definitely true here. :-) > In the 50s the main processor was called the CPU (Central Processing Unit) to differentiate it from the various PPUs, (Peripheral Processing Units). The first machine I programmed, the IBM 7094 had a CPU and two PPUs, one to read cards and write the images to tape transports, which would then be switched over to the CPU to read, compile and execute the job and write the results back to another tape transport which then got switched to the other PPU which then transferred the tape image to a line printer. Thanks. That explains it. > Somehow now (when most peripherals have embedded processors which could be called PPUs) we seem to have stopped using the term. Yeah. It might have gotten lost in the inbetween years when computers were trying to get rid of, at the time, expensive peripherials (they were expensive enough without being their own computer). I only started playing with computers in those inbetween years. :-) Johnny

13 years, 10 months

S-100 board PCB planning

by lynchaj＠yahoo.com

Hi! Over the last couple of years several of us at N8VEM, S100computers.com, and others have been building S-100 boards. This summer we did a major update/respin cycle to the boards and made manufactured PCBs for many builders. For a while it seemed to satisfy the demand for DIY hobbyist S-100 PCBs but now the interest is starting to pick up again so I thought I would send an update to any S-100 enthusiasts on CCTALK. I will reorder/respin S-100 PCBs once the interest level gets to an economically viable level for a group purchase. Normally that is around 25-30 PCBs I know builders want which makes a cost at $20 plus shipping per PCB affordable for most builders. This compromise balance seems to work well and we've produced several S-100 boards this way. Here are the boards we've made so far: S-100 regular prototyping board (some remaining) S-100 buffered prototyping board (some remaining) S-100 backplane (8 slot plus utility circuitry - one left) S-100 IDE (hard drive, CD-ROM, CF, ATAPI, etc) S-100 parallel ASCII keyboard (just received a new batch of respin PCBs) S-100 4MB SRAM (Flash, etc) S-100 system monitor (similar to Jade Bus Probe but two PCB set - one or two remain) S-100 bus extender (with logic probe, indicator LEDs, etc) S-100 EPROM (SRAM, EEPROM, Flash, etc) S-100 IO (dual serial, USB, voice synthesis, etc) S-100 PIC/RTC All of these have gone through at least one or two internal prototype iterations plus one or more manufactured PCB orders. Since we respin the boards based on builder feedback obviously the later generations of boards tend to be "cleaner" than the earlier ones. This is an all volunteer amateur project so the builders *are* the developers, QA, testers, etc in addition to using the boards. There are four boards in active development and/or approaching manufactured PCB stage S-100 Z80 CPU (just ordered first batch of manufactured PCBs after two rounds of prototype build and test) S-100 Console IO (dual Propeller VGA, PS/2 keyboard, microSD, Ethernet, etc - first iteration prototype boards ordered) S-100 ZFDC intelligent floppy drive controller (Z80/WD2793 second iteration prototype board imminent) S-100 68K CPU (first iteration prototype boards ordered) Please note the above boards no longer *planned* they are actual boards in some form or another. There are several more in the planning stages but I won't waste your time with those since those plans change often. All of the schematics, PCB layouts, bill of materials, etc are available on either the N8VEM wiki or S100Computers.com website including build instructions for the most part. These are noncommercial Do It Yourself (DIY) hobbyist PCBs. They are not perfect nor is this a business. John's apt description from comp.os.cpm captures it well "Andrew Lynch (at N8VEM) see (http://n8vem-sbc.pbworks.com/) and I, are in the process of having a few commercial quality S-100 cards made for ourselves. If others are interested in obtaining a bare card, let Andrew or I know. Please note these would be bare cards, a schematic and that's it. Building the board and implementing CPM etc., you are on your own. This is not a project for first timers." In other words, if you want to play along that's great but this is purely "CAVEAT EMPTOR" and there are no assurances, guarantees, or warrantees on any aspect of the boards. Please this is offered as an information post to interested vintage/classic computer hobbyists not an invitation for flames and pointless criticisms. Please be courteous and keep those to yourself. As always, questions, comments and *constructive* criticism welcome. Thanks and have a nice day! Andrew Lynch

13 years, 10 months

Advin PILOT-142 programmer sw?

by chrise＠pobox.com

I was recently given an Advin Systems PILOT-142 device programmer... but of course no software with it. I downloaded Advin's Captain v1.34 software for XP from their website, where they claim support for the model -142 but after installing and launching the software, it reports that it does not work with the "revision" of my programmer. There are no revision or series marks on the unit other than the PILOT-142 sticker above the power switch... so I don't know what makes it different. Email to Advin says they have NO software that supports the -142 even if their website says otherwise. In any case, I'm looking for anyone that might have DOS or Win software for this older beast. It would be a nice unit for burning 2716, 2732 and a number of old PALs that I would like to do. Chris -- Chris Elmquist

13 years, 10 months

Ten P112 kits-a-cookin

by dgriffi＠cs.csubak.edu

The leftover P112 parts have arrived in Portland. We're now working out what more needs to be bought to make kits. There will be ten kits. This means that if all the preorderers take one, the last one who put down for a preorder will not get a kit. I think I've already refunded your money anyhow. If one of the ten declines to take a kit, the will be offered to you (you know who you are). I'll keep the list informed on further developments. -- David Griffith dgriffi at cs.csubak.edu A: Because it fouls the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail?

13 years, 10 months

PDP-11/34A bring up

by chrise＠pobox.com

I am the new keeper of the PDP-11/34A that Jack Rubin rescued a while ago and wrote about here, http://decpicted.blogspot.com/2010/01/pdp-1134a-data-systems-design-dsd-880… I took it on a road trip from Chicago back to St. Paul after VCFMW in September. I've been doing a lot of cleanup on it and finally got to the point where I could power it on (just the CPU box) this weekend. I think now I need to learn about Grant Continuity ;-) There is a M9302 terminator installed in the last slot (left most when looking from the front of the machine) and also an M9312 in slot 4 (amoungst the CPU and cache cards). Two of the original boards are removed from the backplane... the DSD 808830 controller and the DILOG DU130 tape controller. They were in slots 12 and 13. I then also have an RL11 on hand but it is not currently installed in the machine. When I power up the machine, it immediately lights the RUN light on the KY11-B programmer's console. No matter what I do from that console, I cannot get it to exit RUN or print anything to the serial terminal. However, if I remove the M9302 terminator (a trick I found on some web page), then sure enough, I can HALT it, the RUN light goes out and I can do CTRL+BOOT and the serial terminal will spring to life with a register dump and the '@' prompt. I'm pretty sure that my problem is the empty slots 12 and 13 where boards used to be and should now have Grant Continuity cards installed instead... but I am curious why pulling the M9302 makes it "work". What is the mechanism at play there? I also suspect that I may have to look at the backplane wiring for slots 12 and 13 to put back whatever DMA jumpering might have been modified for the two cards that used to be there-- or, at least for one of them as I can probably put the RL11 into one of those slots and it requires DMA. Chris -- Chris Elmquist

13 years, 10 months

Dell Refurbished DEC (?!)

by robert.jarratt＠ntlworld.com

Just noticed a number of items like this one http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=260689944041 appear on eBay. These are strange listings. First I would be very surprised if Dell refurbished vintage DEC stuff. Second it is listed as refurbished but is also described as being in New condition. Has anyone ever dealt with this seller? They seem to have good feedback. I wouldn't buy at that price in any case, but just curious I suppose. Regards Rob

13 years, 10 months

Help with testing Sun CP1500-440

by auringer＠tds.net

Hi all, I recently acquired a SPARCengine 440, which is a CompactPCI form factor SBC. I don't currently have a cPCI chassis in which to test this thing. Normally I would just hang onto this and wait for a chassis to present itself, but I would like to know if the card works before spending resources on the chassis. Is there someone that would be able to help me out with some testing? I think I could make it worth your while. Thanks, -Jon

13 years, 10 months

Amstrad 3in disc drive troubleshooting

by classiccmp＠philpem.me.uk

OK, this is seriously weird. I have two Amstrad 3-inch disc drives: an EME-156, and an EME-231. Both drives will spin up, select and generally "work". For varying values of "work". On both, the "activity" (selected, whatever) LED is stuck on at half-brightness, but switches to full brightness when the drive is selected. For reference: both drives are showing the exact same symptoms. I can select the drive, spin the motor, and seek around the disc. Writing seems to work (more or less) -- when WR GATE goes low, the coils of the head are driven to ~10V with smaller positive and negative pulses (sort of like an exponential curve, synchronised with the falling edge of WRDATA). When WR GATE goes high again, the head voltage falls back to about 2V. When I try and read anything, the head shows no response whatsoever. No pulses on either side of the head at any amplitude (measured with a 1:10 probe on a Tek TDS2024B). Similarly, RD DATA shows no pulses either, except for a brief glitch (2.8us or so) when the drive is selected. The drive controller ASIC also gets rather hot.. like, too hot to touch. I've confirmed that the power is correct -- 12V and 5V have been applied to the correct pins. I'm using "new old stock" Amsoft discs which I bought from an ebay seller. No idea if they're good or bad, but they arrived in shrink-wrapped side-opening plastic boxes and were apparently "Made in Japan." My current suspects are: - Discs. The discs aren't actually magnetically coated in any way, or the coating has failed in some way. Catch is, I don't have a known-good disc to test with. - Heads. Dirty, out of alignment or otherwise completely pooched. Can anyone suggest some things I could check, or are these drives likely to be toast? Thanks, -- Phil. classiccmp at philpem.me.uk http://www.philpem.me.uk/

13 years, 10 months

Crucifixion (was Re: Fragility in the floppy world (was Re: TRS-80 Model II Manuals))

by roger.holmes＠microspot.co.uk

On 7 Nov 2010, at 18:00, cctalk-request at classiccmp.org wrote: > > Message: 7 > Date: Sat, 6 Nov 2010 21:15:55 +0000 (GMT) > From: ard at p850ug1.demon.co.uk (Tony Duell) > Subject: Re: Fragility in the floppy world (was Re: TRS-80 Model II > Manuals) > To: cctalk at classiccmp.org > Message-ID: <m1PEq7C-000J48C at p850ug1> > Content-Type: text/plain > >>>> Oh, go ahead... But I beleive that cucifixion has never been used as a >>>>> suicide method. >>>> No. I've tried it dozens of times; there's just no way you can hammer in >>>> the last nail. >> On Fri, 5 Nov 2010, Tony Duell wrote: >>> I have this image of 4 of those butane-powered nailers used by builders >>> suitably arranged nad with a remote triggger facility. You get your arms >>> and legs in the right places, somehow press the switch and bang... >> >> You might be able to get away with one of the Sears "Nextec" cordless >> electric hammers. > > Except that I am in the wrong country for this. > >> >>> No I am NOT thinking of trying this. >> So, the technique remains untested. > > Do you _really_ want me to try it? Definitely not, for one thing you would not be able to report back the result of the test if successful, only if it failed. A bit like testing the I/O instruction that a torpedo's processor issues to explode its charge, and the code it executes afterwards. The Q.A. department of course would insist that the absence of a detonator and charge might affect the result of the test so must be connected up. We do get into some weird discussions don't we, like guns. What's next? Using classic computers for "sex and drugs and rock and roll"? World domination? Extermination of parasites? Building of DNA molecules to breed a super intelligent organism which will then decide to eliminate what it regards as parasites, the human race? If you must go off at tangents, please at least change the subject line! Roger Holmes

13 years, 10 months

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test-drb November 2010