test-drb

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101090 discussions

by cclist＠sydex.com

Date: Thu, 24 Apr 2008 13:45:10 -0500 From: Jules Richardson > Indeed - in the context of the discussion I got involved in (which was > actually about memory prices, not the PC specifically), we were just > interested in what could be done with a 5150 *when it was new* - and I > think all that IBM offered then was the 64K boards (and of course third > parties didn't exist!) Yup, but vendors like Quadram and Everex came along pretty quickly. Lots of folks realized that the 64K limitation was a huge one. > You know, I had a thought - I wonder if those 64K boards can't be > jumpered beyond the 256KB boundary? Maybe that's why I'm remembering a > 256KB limit on the original machines (and using original IBM expansion > boards). Getting around that would mean physically hacking the address > lines/decoding of the boards... There were also some hacks, since 64K DRAMs were available when the 5150 was launched (why IBM didn't design the planar with jumpers to select memory type is beyond me). If you were handy with a soldering iron and an Xacto knife, you could cut-and-jumper your way to 256K planar memory. The big pain was the soldered-in first row of 16K DRAM. I have a booklet from an outfitlled "Purple Computing" that marketed a little piggyback board that allowed one to leave the first row of DRAM in. It was basically 4 rows of sockets--you still had to do the cutting and jumpering, but without removing the 16K DRAM. Anyone wants the booklet can have it for postage. I was happy to retire my 5150 and get a genuine Taiwanese clone mobo with 256K and 8 slots. Still, PC-DOS would run in 64K. Cheers, Chuck

17 years, 11 months

Selectric Mag Card Print Request

by Jon.Walkwitz＠rice.edu

Hello, I'm trying to find someone who can print an old mag card for a selectric typewriter ca 1973. I can't seem to find anyone around who has got or seen one of these in person (lately). Wondering if you can point me in the right place? Thanks for your help, Jon Walkwitz

17 years, 11 months

Texas Instruments CC40

by mcguire＠neurotica.com

I just remembered that I'd wanted to mention this, but things have been busy and I forgot. My mother knows of my fondness for antique computers, and she keeps her eyes open at thrift stores and related places. She picked up a Texas Instruments Compact Computer 40 for me and presented it to me for my birthday a month ago. I had never heard of this machine, but now I've done some reading and I've played with it a bit. It's pretty neat! Has anyone else here messed with one? -Dave -- Dave McGuire Port Charlotte, FL

17 years, 11 months

IBM 5150 maximum memory?

by Watzman＠neo.rr.com

Re: "I'm not aware of any other mainstream microcomputer introduced in or before 1981 that could support contiguous, directly addressable RAM configurations from 16KB to over 512KB." The Heathkit (Zenith Data Systems) Z-100 supported 768k of addressable contiguous RAM with full color bit mapped graphics video. Generally considered contemporaneous with the PC, but was actually introduced slightly later.

17 years, 11 months

Amiga 4000 Kickstart 3.1 = Dead keyboard??

by snhirsch＠gmail.com

Hi, I just burned myself a pair of Kickstart 3.1 EPROMs for my A4000 and much to my surprise, it no longer recognizes my Northgate Omnikey keyboard! The Amiga keyboard from my 2000 is fine and the Omnikey works on the A2000. VERY strange. Can anyone shed light on this? Were there multiple revisions of 3.1 for the A4000 that I should try? Any help or guesses appreciated! Steve --

17 years, 11 months

Inquiry on System Industries Qbus SCSI

by tiggerlasv＠aim.com

I had put a few feelers out there a few months ago, but was met with silence. It was ominous. You could hear crickets chirping. ;-) One company (Scottish Data Systems) may or may not have the manual; I offered them like $50 + S/H for a real copy, or $40 for an e-mailed copy, but never heard back from them. I may have another source for the manual, but I won't know for a few more weeks. I have not been able to get a FULL description of this board's capabilities. I do know that at least half of the board functions as a SCSI tape controller, with TMSCP emulation, and have been able to get that part of the functionality partially working. Here is what I have so far: SW-2 is a 10-position dip switch at the back of the board. The switch settings are backwards from the norm. Thus, OFF/OPEN switches are a logical "1". 1 = OPEN = OFF 0 = CLOSED = ON Here is the bit decoding: If you copy & paste this into a fixed font (not true type), this should line up properly. I use Notepad in Windoze. SWITCH 10 9 8 7 6 5 4 3 X 2 1 --------------------------------------------- BIT 1 4 2 1 4 2 1 4 2 1 4 O O C C O C O C - C C 7 4 5 0 0 Note the missing bit in the address selection, which correlates to the TMSCP addressing scheme. The 50-pin connector towards the front of the controller appears to be single-ended SCSI. The connector set further back is probably a differential SCSI interface, based on the DS75176's I see directly behind the connector. There are interrupt select jumpers at the back; the jumper closest to the edge is BR4. There is also a BEVENT jumper near the back, center of the board. I have no idea what the function of SW1 is. There is a row of jumpers along the right edge, which may be LUN selection. I'm guessing the jumpers at the front of the board are terminator / terminator power jumpers. So far, I've been able to get the controller address set, and have attached an Exabyte 8200 tape drive to it. When I attempt to boot a tape, it does seem to send commands to the tape drive, and the tape starts to seek. After several seconds however, the processor halts. If I boot RSTS/E, it hangs during INIT before ever getting to a prompt. Clearly, further poking around is required. If anyone has any insight, it would be appreciated, especially the current position of any of the jumpers on your board, and settings for SW1. I will keep you posted. . . T

17 years, 11 months

IBM 5150 maximum memory?

by cclist＠sydex.com

Date: Sat, 26 Apr 2008 10:13:33 -0500 From: Jim Battle > Moore's law was at the time a well known trend, and it wouldn't take a > genius to calculate that the 16-fold increase in memory would be outrun in > just a few years. Yes, but this goes back to the question of "What was this machine intended for?". When one examines it in retrospect, and particularly with a view toward the competition, it's pretty clear that it was intended as a "home" computer for the kids to play educational games on and the adults to balance checkbooks and perhaps write letters on. Given its price, I can certainly appreciate the lack of enthusiasm >from IBM marketing. Indeed, had the same machine been introduced by, say, Tandy, at the same price, it would have met with a much cooler reception. In case of point, a couple of friends had a garage business manufacturing high-end bicycle racks. They needed a small office computer. I had just gotten my 5150 and showed it to them. Underwhelmed, they went out and bought a Morrow (MD2? MD3?) for less cash that was loaded with WordStar and (IIRC) Supercalc. It was ready to go right out of the box. Indeed, there were many other competitors for the "home office/small business" market that offered a much better price point and ease of setup when the whole package was figured in. Eagle II and III boxes come to mind in particular. Eagle used to hold competitions to see who could get from packing box to working system in the smallest amount of time--and I think it was measured in seconds. I think the 8086 caught on sooner in Japan. Mitsubishi and NEC both had offerings before the 5150. The NEC APC, in particular, was a very noteworthy design. Perhaps the need for manipulating Kanji was part of the picture. I suspect that if IBM was considering another CPU, it probably was the 8085. Nice reliable supply (Intel and second sources) and already used in the System 23 box. Given the market IBM appeared to be shooting for, there was no chance of a 68K PC. In marketing's eyes, it would have been overkill. Cheers, Chuck

17 years, 11 months

IBM 5150 maximum memory?

by cclist＠sydex.com

Date: Fri, 25 Apr 2008 22:39:29 +0100 (BST) From: (Tony Duell) > Did very early machines have AC fans? All the later ones certainly had 12V > DC ones that would be independant of mains frequency, but an AC fan would > run slower on 50Hz and could cause the machine to overheat. Was it really > that marginal (Acutally, given it's the IBM PC [1], I could beleive it > was). Yes, they did, but the fans were rated for 50-60 Hz operation and impedance-protected. With the factory, what 62-watt?, PSU, I don't think it was possible to stuff the thing full enough of drives and cards to make it overheat (remember too, that there were only 5 slots) to make it overheat. Wasn't the (black) PSU on the original PC fitted with red tamper-telltales stuck on along the edge of the PSU clamshell? I can't remember exactly, but I think it was. As this was an IBM product, I fully expected that there would have been some provision for changing the AC input voltage. Certainly other personal computers of the time had the feature, and this wasn't supposed to be a product from "Fred's Personal Computer and Aluminum Storm Door Company". One expected a high level of engineering from IBM. [1] When I got my first IBM PC-family machine (a 5160), I took it to bits (what a suprise) and sat down with the TechRef. Every few minutes I'd exclaim 'They did WHAT???' as I found aother it of misdesign... I never understood the design that featured a complete lack of a clear airpath between the plug-in-cards. They must not have been expecting very much expansion. The MDA card was the most bewildering experience to work through-- circuit traces headed off to nowhere, ICs that seemed to perform no function. Perhaps it was designed for graphics operation originally and not completed and rushed to market. Similarly, one suspects that the printer port must originally have been intended as a full bidirectional design and then changed at the last minute--on both the MDA and the printer adapter, all the necessary circuitry was present for bidirectional operation. Cutting and jumpering a single trace was all that was needed. All in all, for as long as the 5150 was in the rumor mill, one would have expected a better thought-through design from IBM. Some aspects were pretty good--the original keyboard was very good; the casework with rolled edges was also notable, although the case design itself was questionable (particularly in mounting/unmounting disk drives). Many Taiwanese vendors improved on the case design by incorporating a hinged lid; I don't know if that met with Part 15 requirements, but it was very convenient. Cheers, Chuck

17 years, 11 months

VT100 board horrors !

by tiggerlasv＠aim.com

Check out e-bay 280220921661 . . . VT100 logic boards, that someone decided to cut the card-edge connectors off of. . . *Sigh* T

17 years, 11 months

help HP 16505A...!!

by fernando.codeel＠free.fr

Hi I've seen you searched the system operater for the prototype analyzer Hp 16505A My system has crashed and it's very hard to find it Can you help me Have you find one image disque for this one ? Thanks Fernando from Paris

17 years, 11 months

Raytheon RAYCAS V Collision Avoidance System manuual

by hardware＠ees1s0.engr.ccny.cuny.edu

Dear cctalk members, I have the manual for the Raytheon RAYCAS V Collision Avoidance System. The sections include setup, operation, theory of operation, and maintenance which includes complete schematics. It is one three-ring binder about three inches thick. If anybody wants this manual, contact me. Historical note: If I remember correctly, it came up in the Exxon Valdez hearings that the disaster could have been avoided by the use of the RAYCAS system that was installed on the ship, but it was not enabled at the time of the disaster because Exxon found the system to be too expensive to maintain. -kurt

17 years, 11 months

early RAM ICs

by hilpert＠cs.ubc.ca

Eric Smith wrote: > Jean-Marie Pichot wrote: > > This display terminal was designed in 1969, [...] Remember, > > in that time, there are no micro-processor, neither RAM chips! > > There were RAM chips in 1969. Most of them stored 16 bits or > less. I have not been able to determine when the first 64-bit RAM > appeared, but it might have occurred by then. Going back to a thread from a week or two ago, and just for the sake of providing a datapoint, while looking for some other IC data in a Motorola 1969 Semiconductor Databook, I noticed: MC1170L PMOS 64-bit RAM - organised as 16 words of 4 bits - binary addressable (4 address lines, 4-bidir data lines) Also ran across mention of: "Intel's first commercial chip, the 3101, a 64-bit static RAM using Schottky TTL" dated at 1969, at: http://homepages.nildram.co.uk/~wylie/ICs/monolith.htm (Nice page if one is interested in early IC developments.)

17 years, 11 months

Inquiry on System Industries Qbus SCSI

by rescue＠hawkmountain.net

System Industries SI-QS 1000 .... Anyone know much about it ? Any docs/data on it anywhere ? This is the first I've heard of this one. Wonder if it is MSCP (I would think so) disk only ? tape only ? disk/tape ? Thanks in advance for any info/pointers. -- Curt

17 years, 11 months

IBM DisplayWriter DOS

by billdeg＠degnanco.com

> Content-Type: text/plain; charset=us-ascii; format=flowed > > I read that there was something sold to make the IBM DisplayWriter > DOS compatible? What would that take? > > I have two of these things with a letter quality daisy wheel and the > giant sheet feeder. SuperCalc and TextPack are boring. > > Is there anything else that can be done with them? CP/M? > > Grant > No. I used to teach Display Write 4 when I worked at IBM, and this came up from time to time in class. There may be a hack where you send the print output to a memory buffer, etc., but nothing official. Bill

17 years, 11 months

Tektronix 7J20

by ericks＠esteinberg.com

Joe, I googled "Tektronix 7J20" and a posting appeared on which you asked a question about this unit. I know that it was 8 years ago, but do you still have your 7J20? Is it for sale? I repaired one of these for a friend and would like to get one for myself. Regards, Erick Steinberg Mill Valley, CA

17 years, 11 months

WTB: Emulex MT-02 controller

by cclist＠sydex.com

Date: Thu, 24 Apr 2008 15:47:39 -0500 From: Jules Richardson > Hmm, maybe the designers were sensible, and any critical timings are > solely on the device response side - i.e. the host can take as long as it > wants to process things, but the device must respond within a certain time > period (and then just happily sits there until the host acknowledges). QIC-02 is buffered via drive-local RAM, so it's not really fussy on the host-side timing. These tapes are streamers, however, so you want to keep the tape moving; otherwise, it's back-up-a-piece-and- take-a-running-start-at-reading-the-next-block. Really slow--and hard on the tape. > Of course none of this probably helps Chuck, who quite possibly doesn't > want to be messing with designing hardware and writing driver software :-) > It's just nice to speculate that it could be done once QIC interface > boards are unobtainable... Oh, Chuck has both QIC-36 and QIC-02 ISA inteface boards. He just wants the convenience of not dealing with buggy NetBSD drivers (the Linux QIC-02 drivers don't work at all anymore) and not having to look for spare DMA and IRQs for the boards. A QIC-02 host interface board is scarcely more complicated than an IDE interface. OTOH, a QIC-36 interface is usually a full-length board, packed with a data separator, CPU, RAM and other logic. From the CPU side, both appear as pretty much the same thing. Cheers, Chuck

17 years, 11 months

Ibm System 32 for sale.

by jos.mar＠bluewin.ch

A local (Switzerland) auction site lists an IBM system 32 for a very moderate 50 CHF ( 50 USD) I'd take it if my time & infrastructe budget would have had any room. Jos

17 years, 11 months

IBM 5150 maximum memory?

by jules.richardson99＠gmail.com

Does anyone recall what the maximum memory was for an original IBM 5150 PC at launch time? The way I recall it, IBM only offered 64KB expansion cards back in the day (256KB ones came later) and the 5150 would only take four of them (wasn't the fifth expansion slot wired differently or something)? That still gives a maximum of 320KB of memory though (4 x 64KB, plus 64Kb on the motherboard) - yet I was remembering the maximum total memory as being 256KB. Maybe just bit-rot on my part. Or did the motherboard memory somehow get disabled if memory expansion boards were in use? Or was there some kind of maximum limit dictated by the 5150's BIOS? I'm sure other things could be done later on via third-party boards of course (or via the 256KB expansion boards), but in the context of the thread that I found myself involved in, the question was what the maximum memory config in a 5150 at launch time was... cheers Jules

17 years, 11 months

IBM 5150 maximum memory?

by cclist＠sydex.com

Date: Thu, 24 Apr 2008 08:38:36 -0500 From: Jules Richardson > Does anyone recall what the maximum memory was for an original IBM 5150 PC > at launch time? Vividly. 64K of 4116-type DRAM chips. The first row was soldered in, the remainder were in sockets. It was possible to purchase a really-stripped-down 5150 through various sources (probably gray- market as I doubt that IBM sold them that way) with no cards or disk drives and only the first 16K installed on the planar. I believe that the San Jose Computerland offered that deal fairly early on. I was never able to determine if they purchased the boxes that way or canibalized the RAM for other machines. There was a DRAM shortage on at the time. Cheers, Chuck

17 years, 11 months

Apple II Echo II card and speaker

by letiathome＠yahoo.com

Hello My name is Leti Meyer and teach Moderately Mentally Impaired folks in Chandler AZ. During the 80's a Company named Edmark made a great functional reading series for the Apple II. I have the soft ware - I have and apple IIgs computer and I have an Echo II card and speaker. What I don't have is drivers to install the echo II device and no clue what slot to put in the computer and how to get it to work. Can you help me??? I would be very grateful. I have 3.5 drive and 5 floppy drives but no way to get the appleIIgs on the web to download the drivers. I will send a picture of my students using it if someone helps me :)

17 years, 11 months

digilog 800 protocol analyser

by hilpert＠cs.ubc.ca

I received a Digilog 800 protocol analyser a while ago. It's essentially a portable/luggable (50 lbs(!)) multibus-based computer from 1985 with: - built-in 10" colour monitor - flip-down keyboard - ST-2<something> hard-disk (ST-225?) - 3.5" floppy - 6-slot multibus backplane - three(!) 80186 CPUs along with an AMD 29116 and an 8085. The multibus boards all appear to be of proprietary design, rather than some off-the-shelf boards. I don't know why there are so many 80186's. I suppose one might construe it as an unintended comment on the computing power of the '186. A little googling finds some period marketing info: "the model 800 operates at 256 kb/s, is equipped with a 10-Mb Winchester disk and has nine soft-function keys and a 10.5-inch color CRT." and refers to it as a "4th generation protocol analyser". Powered up it goes though a couple of self-tests, fails on a Winchester boot problem, requests a system floppy be inserted (which of course I don't have) and hangs, and of course I received no manuals. On the one hand it was pretty good stuff for it's time, might be an interesting architecture, and speaks to a particular time and need in networking development. On the other hand, the lack of docs, complexity, and limited and outdated target application leave me with difficulty coming up with a compelling reason not to scrap it. Anyone know anything more about it, or have any interest in it? (location is Vancouver, B.C. area)

17 years, 11 months

12 and 8 volt transformer

by dgriffi＠cs.csubak.edu

Someone on this list is buying an S100 chassis from me and had me remove the 18-pound transformer to save on shipping. This transformer is now available to anyone on this list for $10 plus shipping. Since it's small enough to fit in a flat-rate US Priority box, I presume shipping will be $8 to $10. Because it has two bobbins and was the only one in the chassis, I presume it outputs both 12 and 8 volts. And you, the buyer of the chassis, I've finally gotten to the bottom of the messes that were in the way of proceeding. More info is in your email spool. -- David Griffith dgriffi at cs.csubak.edu

17 years, 11 months

SEIKOSHA SP1000VC

by g7460b＠ptd.net

i have the same printer. can you tell me what kind of cord it takes and if you know if it can be used on a current computer? Gary

17 years, 11 months

WTB: Emulex MT-02 controller

by cclist＠sydex.com

Date: Thu, 24 Apr 2008 21:05:12 +0100 (BST) From: (Tony Duell) > I would be suprised if the QIC02 specificiation isn't avaiable > somewhere... Oddly, it's not on the http://www.qic.org site, but you can find both it and the QIC-36 signal descriptions in the Wangtek PC-02 and PC-36 tech manuals on bitsavers. Cheers, Chuck

17 years, 11 months

wtd: IBM 3279 keyboard

by drb＠msu.edu

Anyone have a "spare" keyboard for an IBM 3279 terminal? Scored a kb-less terminal which seems functional from Salvage the other day. De

17 years, 11 months

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