test-drb December 2007

test-drb@ccmp.vtda.org

215 participants
420 discussions

by fsmith＠ladylinux.com

Hi, I think its been over a week now as far as I can see. Just wondering if this is just me not being able to get to this site. Has it gone away ?? http://www.vintagecomputermarketplace.com/ -- Kindest Regards, Francesca Smith "No Problems Only Solutions" Lady Linux Internet Services Baltimore, Maryland 21217

17 years, 4 months

FREE: CDC CMD948

by tponsford＠rnsmte.com

Hi All One of the good things, or bad things, about being the "antique computer guy" at our local auctions is that I'm a frequent recipient of all things old, obsolete, or just unwanted. Someone mistakingly bought a lot item he did not want so rather than trashing it, he gave to me. I felt it was unique enough that maybe some of the brethren on ccomp might want it. It's a Control Data CMD 9448-96 "phoenix" modular (removable/fixed) disk drive in unknown condition. It reminds me of a RL01/02 disk. It looks to have everything there but until I find a manual, I know little about it. It is supposed to have a capacity around 80MB, has a 14" platter and is real heavy; 120+ lbs, so shipping is probably out of the question. If anyone wants it. It's yours for the taking as long as you come get it. I'm in SE Arizona outside of Tucson (near tombstone) and I do make trips to Phoenix or El Paso from time to time! I'll keep it around in my storage shed for a while at least! Cheers Tom Ponsford

17 years, 4 months

Curiosity on eBay UK: "antique" Video Conferencing System

by classiccmp.org＠stellar.eclipse.co.uk

Item number: 270198584951 <http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=270198584951> A Google returns this 1993 article in which the product is mentioned: Just before Christmas, BT launched its VC7000 conference unit (made by Tandberg in Norway). This is a low-cost digital videophone, with a 25-centimetre colour cathode-ray tube screen which is switchable between 64 and 128 kbit/s working. It costs ?7500. BT puts the cost of an hour's video call at 128 kbit/s to the US at ?168, but Mercury promises to undercut this by nearly ?40. Call cost can be halved by switching the phone to work at 64 kbit/s, but most serious users prefer to pay more to get the better pictures and clearer sound available from 128 kbit/s working. The British telecommunications giant GPT is also selling 64-128 kbit/s systems, with screens measuring up to 70 centimetres, for around ?40 000.

17 years, 4 months

5.25 drive with sector output

by ard＠p850ug1.demon.co.uk

> The next question is, do the older drives have a filter on > them such that they would not output the index along with > the sector pulse? The normal way to separate index form secotr pulses was to have a non-retriggerable monostable that was triggered from the index sensor and which had a period a little less than the time between sector holes. It was triggered at the end of each hole. Normally it timed out after each sector hole, but was still set when the index hole came after the last sectore hole. The output of said monostabel sent the output of the index hole sesnor to either the 'sector' line or the 'index' line. What do you mean by 'older drives'? AFAIK no half-height 5.25" drive has such a feature. > The drive I'm planning on using is an old Qume drive with > a IBM lable on the front. It is a QUMETRAK 142. It is IIRC that's the drive used in the PortablePC and PCjr. In which case I'll have the schematics for it. Hang on... The index sensor on that drive goes into a schmitt trigger circuit using U16 f and U16c ('LS14). The output of that goes to U10c ('38) and thence tiooe the interface connector. TP7 is the index testpoint. There's no monostable, or filtering, or anytthing like that on this drive. Some drives, particularly 3.5" ones, have an adjustable monostable in the index circuit which lets you delay the index pulse. It's adjusted when the drive is aloighed to give the correct timing between the index pulse and the data ffrom the ehad -- twiddlign the pot is easier than moving the index sensor. Such a circuit could msess up what you're trying to do, but this IBM drive doesn't have anything like that. > good to work on because it is all descrete parts and > TTL ( some analog IC's as well ). Still, if they have a > filter on the index, I should be able to modify it. > I only see one pot in that area of the board and I suspect > that it is for the pulse witdh of the index. I can find 2 pots on the schrmatic. R56 (connected ot U1, an LM2917), sets the spidnle motor speed. R63, connectrd to U2 (MC3740) is the common read-data balance adjustment. -tony

17 years, 4 months

Yet another VT-100 emulator

by dm561＠torfree.net

Date: Mon, 24 Dec 2007 01:20:15 -0000 From: "Ensor" <classiccmp at memory-alpha.org.uk> Subject: Re: Yet another VT-100 emulator <snip> >But like everyone else, you've missed the point. The OP was originally >asking about standard IBM cards, not about VESA "standard" cards which are a >different kettly of fish.... >TTFN - Pete. ------------ Actually, I think *you*'re missing the point of this whole thread, which is the feasibility of 132 column mode in Dave's VT-100 emulator; FYI I'll quote the OP: ... "Does anyone know if any of the more modern (ie: VGA) cards support enhanced 132 column text modes? - And is the video addressing basically the same except for 132 words of memory per line instead of 80? And where to find more information? If it could be reliably determined that support was there, and it is compatible with my text windowing code, it would not be difficult to add support for it." ... m

17 years, 4 months

What is a Heathkit H120?

by legalize＠xmission.com

Supposedly its a computer, but I can't seem to find anything on the net about it. old-computers.com in particular let me down. -- "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, 4 months

Clearout, final offers [UK]

by classiccmp＠memory-alpha.org.uk

One last try, this stuff is going to start getting junked at the end of this week unless someone pipes up: --Monitors-- SGI 19" Colour Monitor (white in colour, unknown model #) Philips MDA/Hercules Monitor --Terminals-- Televideo 950 (*2, spares or repair) Wyse 30 Zenith Z89 (spares or repair) --Computers-- Power Macintosh (Dunno model # offhand) BBC Micro (*2) CBM PET (at least 3, plus floppy drive units) Tandon PAC-286 (c/w kbd, monitor, printer) --Printers-- HP LaserJet+ IBM ProPrinter XL24 (unknown condition) --Other-- Philips CDD-462 External CD-ROM drive Odd stand alone NCR tape drive unit Telexbox III (possibly *2) BT Modem rack (contains some 10 14k modem cards) Philips BSB Satellite Receiver (*3) Tatung BSB Satellite Receiver Panasonic Analogue Satellite Receiver "Micro Decision" magazines from 1989/90 There's a reasonable amount of other stuff which I haven't been able to get at to catalogue yet which will also be on offer. Please contact me directly at "ensor" at the domain name this message came >from for more details or if you're interested in any of this stuff as I'll be quitting the list over the next couple of days. TTFN - Pete.

17 years, 4 months

Yet another VT-100 emulator

by classiccmp＠memory-alpha.org.uk

>> But like everyone else, you've missed the point.... > That must be why didn't add VESA 132-column mode to his VT100 >emuatlor.... Which is something which came along sometime AFTER the original question was posed, moron....

17 years, 4 months

Yet another VT-100 emulator

by dm561＠torfree.net

---------Original Message: Date: Wed, 19 Dec 2007 01:37:08 -0000 From: "Ensor" <classiccmp at memory-alpha.org.uk> Subject: Re: Yet another VT-100 emulator Hi, >>> Not likely - as far as I know there are no standard PC text >>>video modes that give 132 columns. >> >> Long ago I had a 132char driver for the Hercules/TTL mono video >>card. I was based on the 720x348 mono graphics mode. > > As far as I know there are no **STANDARD** PC text video modes >that give 132 columns. Precisely, just what is so difficult about that statement for people on this list to understand!!?? The bottom line is that the **ONLY** ***STANDARD*** text modes supported by EGA and VGA adapters are 40 and 80 column. END OF ARGUMENT. PERIOD. Whilst it is perfectly true that most/all "SuperVGA" cards support one or more 132 column text modes, these modes - along with their mode numbers - are unique to each manufacturer and indeed often differ between chipsets >from the same manufacturer! Great if you want to tie your software to working with only a single brand of chipset/graphics card (which I doubt is what the OP wants), but otherwise utterly useless.... <snip> The OP needs modes which work on ALL adapters, not non-standard modes which work on a small number of Mickey Mouse cards which noone uses.... TTFN - Pete. ---------Reply: VESA will be disappointed to hear that their VBE standard which does define four 132-column modes (109 - 10C) is not a "standard" at all (insofar as anything in this field can be considered "standard.") http://en.wikipedia.org/wiki/VESA_BIOS_Extensions I'd say a Mickey Mouse card is one that does *not* implement the VESA extensions, and I think there's more than just one brand that *does*... But if you think we should all be restricted to EGA and VGA modes (who actually has an EGA or VGA card and/or monitor?) then who am I to argue; I personally find 132 columns useful at times. mike

17 years, 4 months

5.25 drive with sector output

by cclist＠sydex.com

From: ard at p850ug1.demon.co.uk > The normal way to separate index form secotr pulses was to have a > non-retriggerable monostable that was triggered from the index sensor and > which had a period a little less than the time between sector holes. It > was triggered at the end of each hole. Normally it timed out after each > sector hole, but was still set when the index hole came after the last > sectore hole. The output of said monostabel sent the output of the index > hole sesnor to either the 'sector' line or the 'index' line. The period of the monostable is pretty flexible--anything longer than half the time between sectors and less than the time between sectors will work. If you're "back of the envelope-ing" it, you might shoot for 75% of the time between sectors. This would allow a pot-less design, as the component tolerances would be well within the "slop" allowed in timing. > Some drives, particularly 3.5" ones, have an adjustable monostable in the > index circuit which lets you delay the index pulse. It's adjusted when the > drive is aloighed to give the correct timing between the index pulse and > the data ffrom the ehad -- twiddlign the pot is easier than moving the > index sensor. Such a circuit could msess up what you're trying to do, but > this IBM drive doesn't have anything like that. Most newer 3.5" drives subsume the "ready" circuit into a monolithic hunk of silicon with the rest of the drive control. Index output pulses are blocked until the period between indexes satisfies some internal "ready" standard. Also, 3.5" drives can have *very* wide index pulses when compared to 5.25" and 8" drives. Of course, any 5.25" drive with this logic (and it's very common) will view a hard-sector disk as not being anywhere near the correct speed, so will not only not come ready, but will block *all* index pulses going out. This feature has a curious implication if you decide to replace an older drive without the "block index until ready" logic with a newer drive with that logic. Many controllers (such as the WD1770) or software will count up a few sectors after select or motor on before commencing an operation. The result is that everything still works, but the latency after selecting a drive increases significantly. Note that once the drive been selected and come ready, this is not an issue. For what it's worth, Chuck

17 years, 4 months

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test-drb December 2007