test-drb April 2008

test-drb@ccmp.vtda.org

196 participants
307 discussions

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 --

16 years

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

16 years

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

16 years

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

16 years

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

16 years

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

16 years

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

16 years

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.)

16 years

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

16 years

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

16 years

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test-drb April 2008