test-drb January 2007

test-drb@ccmp.vtda.org

238 participants
538 discussions

Wire Rope ROMs (Was: back to the AGC, was Re: TTL 7400's Available)

by rickb＠bensene.com

Brent Hilpert wrote: > > .... I'm familiar with > core-rope ROM (or at least one version of it) from attempting > to make a reader to dump the contents of a Wang calc > microcode ROM, but the AGC version sounds like the > address-decoding/word-selection is done differently (..need a > diagram). Speaking of Wang Calculator ROM's, I've recently built a fixture that I'm successfully able to read Wang 700-series ROMs with. It's unfortunately a non-automatic system...toggle switches and TIL-311 HEX displays (can automate it later), and am in the (slow) process of dumping a known good Wang 720C ROM. The ROM strobe signal timing is very tight on the 700-series ROM...off even a little bit on the timing (pulse width), and the readout gets real inconsistent. Also trying to write a microcode execution engine in Perl to run the code, but there are lots of interesting timing considerations that require deep digging into the schematics (which is something that I have little patience for...basically, I'm not very good at it) in terms of the timing of all of the register transfers in the machine. On the surface, it looks simple, just a basic 10-phase non-overlapping clock (shift register), but there's a lot of combinatorial logic that derives a lot of weird timing from the basic clock phases. So far, my attempts to execute the code I've extracted so far lead to execution of illegal instructions (all zero ROM locations), or infinte loops, and the code execution doesn't seem to make much sense. There are also some microcode instructions that aren't documented, and having to dig through schematics to figure out what they do. Wang is also famous for purposefully putting errors into published schematics to throw off competitors who would use such schematics to reverse-engineer how the machines work. So, some of my problem could be that the schematics are not necessarily an accurate representation of the actual logic. Still some tinkering to do. Still, I'm very sure that the fixture to read the ROMs is working perfectly. All ROM locations return consistent results, and other than the emulator running into all zero ROM content (there are quite a few "unused" locations in the ROM), all of the instructions decoded thus far are "valid" in terms of the allowed values of the various microcode fields. The Wang 700, 500, and 600-series machines all used this style of ROM, so, in theory, the reader (other than hardware pinout variations and subtle microcode field diffrences) should be able to be tweeked to read the 500 or 600-series ROMs without too much work. The main goal of this is to be able to capture the microcode images for as many of the Wang calculators that use this type of ROM as possible, as this technology is really unweildly to troubleshoot and repair (and I have some ROMs that are known bad that I want to try to be able to fix), and also because the genius of Harold Koplow (now deceased) is buried in that microcode. I want to preserve as much of it as I can (and maybe figure out how he made these machines do what they do) as a legacy to him. Rick Bensene The Old Calculator Web Museum http://oldcalculatormuseum.com

17 years, 11 months

questions about Sphere-1 micro? email me.

by legalize＠xmission.com

The Sphere-1 micro, the first personal computer, was created and built here in Utah. The creator, Mike Wise, died from complications of diabetes in December of 2004. However, one of his long-time business associates Arnold Grundvig of A-Systems is still around. <http://www.a-systems.net/company.htm> I talked with Arnold on the phone and he says that Mike regaled him with many stories over the years about the Sphere and so-on. I was interested in interviewing Mike for a short peice about that early piece of Utah computing history. Arnold has agreed to be interviewed for such a purpose instead. So if any of you have questions about the Sphere or that period of microcomputing history, please email them to me off-list and I will collect them together with my own questions, conduct an interview and post the transcript. If any of you know any "old timers" that are getting on in years, it might be a good idea to conduct a recorded interview (don't rely on notes! record it!) to capture some of the "oral history" that will be lost when they pass on. -- "The Direct3D Graphics Pipeline" -- DirectX 9 draft available for download <http://www.xmission.com/~legalize/book/download/index.html> Legalize Adulthood! <http://blogs.xmission.com/legalize/>

17 years, 11 months

Keyboard question

by sdc695＠yahoo.com

While not exactly computer directly related, since the silly box does have a computer in it, I'd thought I'd ask here. I've got an old TV Character generator, a Laird CG7000 to be exact. It has a nice standard 5 pin DIN connector on the front panel for its "keyboard". Now to me this looks just like a standard AT type keyboard, but alas it does nothing unless I beat on the keys then something might show up. Would anyone know what type of keyboard they use for this silly thing. It is a bit old, and I suspect it might be an XT (not an AT) keyboard (which are different). I'm going to attempt to trace out the connections to figure it out, but if someone on the list has a clue, it would be helpful to me. Not wanting to clog things up further, a response off list if probably the best. Thanks. -- Tom Watson tsw at johana.com __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

17 years, 11 months

Missing Bits

by dm561＠torfree.net

Date: Wed, 3 Jan 2007 17:48:11 -0800 From: "Billy Pettit" <Billy.Pettit at wdc.com> Subject: Missing Bits -------------Original Message: <snip> Recently, I've been trying to write up some of those experiences and found that I have almost nothing on a lot of the companies. <snip> And one that is driving me crazy, a company that supplied Ada systems to the military. Was first based in Mt. View, then moved to San Jose into one of the old Amdahl buildings. I can visualize the people and systems but can't remember the name. Getting old sucks. I'd love to hear about anyone's experience with any of these companies and especially if any documents or hardware survived. And I'm especially interested in ARIX. It was a very unusual company, and obliquely mentioned in the 6 part TV series on Silicon Valley. Billy -----------Reply: I worked with an Arix system years ago, and I think at least one person up here in Ontario has one; I sent him whatever Arix documentation I had left a while ago. Dave Dunfield might know better if they're still around and who has them now. mike

17 years, 11 months

Arix (was Rational)

by Billy.Pettit＠wdc.com

Al Kossow wrote: Did you mean Arete? We have one, and it ran a version of Unix called Arix. ------------------------------ Billy wrote: My memory is that the first few times I visited them, the company name was Arix. That was changed to Ar?te after some of the notoriety caught up with them. I'd love to meet somebody who worked at the location on Zanker road. There were things happening there that are unique in the industry. Does anybody on this list remember the room painted black? Billy

17 years, 11 months

Stuff to give away UK

by williams.dan＠gmail.com

I have some more stuff to get rid of now. There are: 3 Vaxstations Some Amstrad CPC's Manuals I don't have equipment for : Tektronix 475 oscilloscope calibration and diagram supplement la120 letter printer programmer ref guide tektronix 475 oscilloscope service manual beckmen industrial circuitmate 9020 osilloscope operaters manual x3 cosser instruments model 3122 oscilloscope operating manual cosser instruments model 3100 oscilloscope operating manual cosser instruments model 3102 oscilloscope operating manual some vt100's with no keyboards Lots of sparcstation IPC's Apart from the manuals anything not picked up will have to be skipped. Stuff not so free. I would like some cash for, anything sensible will be accepted. Would also accept storeage of other items for a year or two ;) vax 4000/500 with external 10x external drives (all with scsi->dssi convertors) (in half rack) vax 4000/705A with external 5x dssi drives. (In standard case) Dual head octane with 1gb memory. vaxstation 4000/90. The stuff is located in Soho at the moment. It could move to Kent if not picked up soon. Thanks Dan

17 years, 11 months

govliq messages

by legalize＠xmission.com

Govliquidation.com doesn't exactly have the best descriptions, pictures, or search engine, but it does have lots of interesting stuff popping up there from time-to-time. Because its such a pain to find things on there, when I stumble across something that someone here might find interesting, I post a note with the lot link. Does anyone find this useful? Does anyone find this annoying? If its more annoying than useful, I'll stop giving y'all a heads up on these items. -- "The Direct3D Graphics Pipeline" -- DirectX 9 draft available for download <http://www.xmission.com/~legalize/book/download/index.html> Legalize Adulthood! <http://blogs.xmission.com/legalize/>

17 years, 11 months

not quite on topic but, classic analogue satellite tv decoding boxes

by witchy＠binarydinosaurs.co.uk

Hello folks, I've got a pair of old UK SKY TV boxen (1997 era) that are pretty useless as analogue SKY TV was switched off in 2001; can the hardware be used for anything else or is it pretty much paperweight material? Ta, -- adrian/witchy Binary Dinosaurs creator/curator www.binarydinosaurs.co.uk - the UKs biggest home computer collection?

17 years, 11 months

Purposefully fudged schematics

by Billy.Pettit＠wdc.com

Chuck Guzis wrote: To be certain, some errors/additions are deliberate; Rand McNally generally sprikles a few non-existent landmarks in their maps; Google satellite maps have "watermarks" that can be very confusing. I spied what looked to be clearing on some of my forested land and hiked to the very spot and found--trees, just like everywhere else. It took some conferring with a USGS employee to discover that what I thought was a clearing was a rather subtle watermark (viewed in just the right way, you can make out a "Go". Cheers, Chuck ------------------------------------- Billy wrote: It also happens closer to home in our mutual field. In the 1970's, CDC was working hard on Russian alliances. They had to prove that Russian technology was as advanced as the products CDC wanted to ship. (The old DoD guideline.) So they bought some Russian 8080's and tested them. Everything was going good until they decapped the chip. Inside, under a microscope, they found an image of Mickey Mouse's head in the metal layer. Of course, put there by Intel engineers to spot copy cat reverse engineering. The Russians hadn't caught up in technology; they had bought masks under the table and made complete ripoffs. I know other IC vendors use similiar tricks to identify their IP. One I have seen is an entire section of circuitry that has no outputs - like the old famous write only logic. And it has been faithfully copied by several Asian suppliers. Billy

17 years, 11 months

D-shell connector age?

by julesrichardsonuk＠yahoo.co.uk

Anyone know where D-shell connectors first appeared on equipment? Interesting thread going on in a local group at the moment about why SCART [1] sockets are so horrible and nasty (prone to breaking pins, difficult to line up, prone to falling out etc.) and why something better, like a D-shell connector, wasn't chosen instead. Thing is, SCART was apparently first used in consumer A/V equipment in 1977, which probably means it was thought up in the mid-70's. Edge connectors and/or circular DIN connectors were probably more common on computer equipment of that time, but were D-shell types around by then too? [1] For the non-Europeans, SCART is common on all A/V equipment in Europe and provides component RGB (as well as composite) interconnect between devices, along with stereo audio channels, sync lines, remote device standby control etc. cheers Jules

17 years, 11 months

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test-drb January 2007