test-drb

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101090 discussions

New finds this week / Cheap to a good home

by pat＠purdueriots.com

I managed to get a few fun things to play with this week - courtesy of Purdue University Salvage/Surplus ** Finds ** Lear-Sigler AMD-3A+ **actually working** (compared to my ADM-5) $free 4 x Pioneer CD CDV LD Player CLD-2400 (LaserDisk player) $free OT: 2 x SYMBIOS RAID arrays - 10 drives/controller, 2 controllers/array with the 4GB narrow scsi drives in it, total of 144GB of RAID-5 pulled from an NCR Teradata (worldmark 5100M) system 2 x NCR Worldmark 5100M nodes with 4GB Ram, 32xPentium Pro 200MHz processors each. Now, it's time to help with its Linux port - doesn't quite boot yet. Features a pair of 32bit Microchannel busses per node. Technically, I guess, it's still Purdue's, but I get basically exclusive access to it (and free power/network). I'm thinking about going back to grab a pair of marked 'BAD' ADM-5's from there that might be useful for parts to repair my ADM-5. ** Cheap to a good home ** Assuming all the Laserdisk players all work - they just have a few cosmetic scratches - I'm willing to part with two of them. First two replies get them for $10 + shipping. If they don't all work (as far as I can tell without owning a laserdisk - they should also play CDs) then I'll be offering less of them I guess... Pat Lafayette, IN, USA -- Purdue Universtiy ITAP/RCS Information Technology at Purdue Research Computing and Storage http://www-rcd.cc.purdue.edu

23 years, 4 months

BBC Acorn

by pete＠dunnington.u-net.com

On Dec 14, 0:37, Tony Duell wrote: > > upset if people wrote "Disk" instead of "Disc"). As far as Acorn were > > concerned, BASIC (even BBC BASIC) is "just another language". > > IIRC, BASIC is a somewhat odd language that doesn't implement one of the > 'standard' entry points. But it is a language ROM. Indeed, it has zeros in the service entry point which wouldn't be legal for an ordinary language ROM, except that it is treated as a special case by certain Acorn firmware, and that missing service entry is used in the first stage of recognising which ROM is BASIC. It's unique in that regard. -- Pete Peter Turnbull Network Manager University of York

23 years, 4 months

BBC Acorn

by pete＠dunnington.u-net.com

On Dec 13, 21:11, Tony Duell wrote: > This reminds me of something that suprises me. Namely that the Model A > missed out some fairly simple/cheap chips like the buffers for the 1MHz > bus and/or Tube, the RS423 buffers (the rest of the serial I/O system was > fitted on the A becuase it was needed for the cassette I/O), etc. I would > have thought that the cost of fitting sockets and having 2 different > boards in production would have exceeded the cost of these chips... The idea was to keep the cost as low as possible while making it simple to upgrade. At that time the sockets would have been much cheaper than the chips. I don't know how the decision was made, nor by whom (though Acorn was a fairly small comapany at that time), and it may have involved the BBC. > > I doubt if it's that simple. UK models don't use mylar ribbons, they use a > > single 17-way notched IDT cable with a 0.1" pitch, and with a single-row > > Unless thr speech upgrade is fitted. True, in which case there's an additional 10-way 0.1" pitch IDT cable on the left of the keyboard. > Very early Beebs had linear PSUs with 3 7805 regulators in them. One fed > each of the +5V outputs. You (Joe) do not have one of these, though. :-) Horrible things. Acorn had an exchange scheme, and they destroyed the black ones they got back. There were actually three black models, two matt black, one gloss, IIRC. One (I forget which) was unofficially known as the "adaptor and exploder" becasue it had a habit of doing the latter. > IIRC, the ground pins are linked on the mainboard, the +5V pins are not, > so you have to have all 3 sets connected for it to work. Later boards did have the +5V joined up, just not with very fat tracks in places. So on all but the earliest ones, it sometimes "mostly" works if one set isn't connected (or is dirty). -- Pete Peter Turnbull Network Manager University of York

23 years, 4 months

New finds this week / Cheap to a good home

by healyzh＠aracnet.com

> --- Patrick Finnegan <pat(a)purdueriots.com> wrote: > > > What brand and model? My Pioneer plays cd's, but it has a cd drawer > > > within the laserdisc drawer. > > > > It's a CLD-V2400. It claims to play LD's CD's and CDV's (CD with Video). > > Ooh! If I didn't already have an LD-V8000 (for playing Dragon's Lair > and my LD collection), I'd love to have one - I have a Moody Blues > CD-Video - 4 CDDA audio tracks and one Pioneer-Laser-Disc-style video > track that only plays in certain players... like the ones you have. > > -ethan Oh, come on Ethan, you should know the primary rule of having a Laserdisc collection, you can never have enough players. We've got three players at home that we use and two more (three if you count the broken one) in storage. Still, I'm trying to slowly convert the most important LD's in our collection to DVD-R as I'm worried about bit-rot and the players slowly dying. Sadly there is stuff on LD that will probably never make it to DVD (I'd love Anamorphic Widescreen copies of some of our LD's). Zane

23 years, 4 months

BBC Acorn

by pete＠dunnington.u-net.com

On Dec 13, 11:20, Joe wrote: > At 10:06 AM 12/13/02 GMT, Pete wrote: > > > >How many (EP)ROMs are in it? Do they have any numbers on them? > > There are five sockets in a row (IC71 - IC75) but IC 75 is empty. IC 71 is an EPROM but the label in missing. IC 72 is a Hitachci PROM marked HN613128PD11 View2-1 Japan (c)ACORNSOFT, IC 73 is an EPROM and is marked DNFS 201666, IC 74 is an EPROM and is marked US BASIC 201667. Behind that row is IC 52, it's marked VI (I THINK, it's stylized and hard to read), then 403 V 2006 VC 2023 201647 (c)ACORN COMPUTER KOREA-AE. I think that's all of the custom ICs. Interesting. The IC numbering scheme is different. I know Acorn slightly modified the video circuit for the US, so I suppose they renumbered IC positions at the same time. The first one (missing a label) should be the MOS. It makes sense that it would be an EPROM, because Acorn regularly used EPROMs rather than mask ROMs for "low" volume runs, which I'd expect the US MOS to be. I discovered that pages 478-479 of the Advanced User Guide list the differences between US and UK MOS versions. Basically, the US screen resolutions are the same width but less high (corresponding to 1280 x 800 points instead of 1280 x 1024 -- points are not pixels though, the correspondence depends on the screen mode, which determines the resolution used). This is because the frame rate is 60Hz instead of 50Hz, and also means that the screen memory usage is correspondingly lower in some modes. The next four ROMs are "sideways ROMs" which share the same address space, being switched in and out by the MOS. They will be prioritised from left to right, right being highest priority. When the machine starts up, it checks each socket looking for language, filing system, and service ROMs. Simplifying a little, it gives each a chance to initialise, and then allows the highest priority filing system and highest priority language to start fully. VIEW is a word processor, which in Acorn terms is a "language" ROM. The version you have is the standard version 2. DNFS is a combinatin of Disc Filing System (for 8271 floppy controller), Network Filing System (for Econet[1]), and Tube utilites (for a Second Processor). Part number 201666 is the standard DNFS, same as the UK. The sign-on message should be "Acorn DFS" (unless you have the Econet network interface fitted and either have changed a link to make NFS take priority or have removed the 8271). [1] I read somewhere that US machines were fitted with Econet as standard. If yours has the interface, there will be a 68B54 ADLC chip in the North West quadrant of the board, a 180-degree 5-pin DIN socket on the back, and few or no empty positions for components around the ADLC position. And if you hold down the "N" key while starting it up, it should say "Econet Station 001 No Clock" instead of "Acorn DFS". The station number would be different if someone has changed the links in the block of 8 near the Econet socket. Incidentally, holding down various keys can force filing system selection regardless of ROM priority and link settings, providing the relevant hardware and firmware is present. "D" for DFS, "N" for NFS (Econet), <space> or <DELETE> for tape, "R" for RFS, "A" for ADFS ("F" for fast-start ADFS), etc. "US BASIC" is fairly self-explanatory. Like Tony, I'd be very surprised if it were supposed to say "BASIC OS" because BASIC is not an OS and Acorn were quite particular about terminology in many ways (they even used to get upset if people wrote "Disk" instead of "Disc"). As far as Acorn were concerned, BASIC (even BBC BASIC) is "just another language". The two other similar ICs are the serial processor (near the back) and video processor (near the ROMs). The stylised VI is the VTi logo. > >> Actually I didn't get a cursor. I wasn't sure if it was supposed to > >have one or not. > > > >Yes, you should. > > Hmm. Sounds like it's not finishing the boot sequence. I think it's getting something wrong, given all those "OS" appended to startup messages. I'd suggest *carefully* lifting all the socketed ICs and re-seating them. I'd also suggest you temporarily remove the VIEW ROM and see if there's any difference. Once you have a working PSU, of course. BTW, if you're repairing that PSU, it's a switchmode. Beware of high voltages on the capacitors (including their cases) and on the heatsink for the power transistor. However, the standard Beeb supply (an Astec unit) is safe to run with no load (unlike some SMPSUs), and it will shut down safely (making a characteristic tick-tick-tick noise) if the +5V output is shorted, and will immediately start up again if the short is removed. -- Pete Peter Turnbull Network Manager University of York

23 years, 4 months

Pulling -12VDC from thin air (was Re: MicroVAX II)

by dwightk.elvey＠amd.com

>From: "Ethan Dicks" <erd_6502(a)yahoo.com> > > >--- Jochen Kunz <jkunz(a)unixag-kl.fh-kl.de> wrote: >> I second that. I know a collector who knows nothing about hardware and >> how it works.... When I told him that I builded a simple voltage >> inverter (charge pump) to make the RS232 work on the Sun 4/600 MP he >> looked like it was black magic to convert +12V to -12V. (The Sun 4/600 >> MP boards needs -12V for the RS232, even -5V are not enough. As I >> mounted this board in a Sun 3/60 case that doesn't provide -12V, I could >> not use a serial console.) > >Interesting to learn about the 4/600 board and the 3/60 case. Long ago, >I wondered if the two could work together (I _have_ the 3/60 and I almost >had the 4/600 board). > >If you'd have known to ask, I could have provided you with a +5VDC to >-12VDC converter module. It's about 20mm x 30mm x 3mm. We had to put >them on the Qbus COMBOARD because the original design assumed you could >pull -12VDC off some Qbus pin somewhere, and I suspect that it is not >the case for all Qbus enclosures (don't know where it is available and >where it isn't). I have several new on the anti-static mat they shipped >in. > >-ethan > Hi There is another chip in the MAX232 series someplace that creates +/- 12 V from 5V for serial uses other that what a 232 chip is normally used for. It just needs some capacitors for the charge pumps. Dwight

23 years, 4 months

OT: Re: Interesting Tim O'Reilly article.

by Robert_Feldman＠jdedwards.com

When I had just a record player (sometime back BCE), I had just one turntable, and one copy of each record. If I wanted to listen to the music on a record while at work, I could make a cassette tape copy. I wouldn't go out and buy a second copy of the LP. (The only time I have done that was when I found a cutout copy of an out-of-print LP that I liked a lot, and wanted to have a backup copy.) Now we have 4 CD players at home and I have one in my computer at work. If I want to listen to one of my CDs at work, I will make a CD copy of the original CD that I own. I have also made CD copies to have one upstairs and one downstairs. I would not go out and buy a second copy of any of the CDs if I was unable to make copies -- I would just ferry originals between home and work. With multiple copies, is my wife listening to the same one at home as I am listing to at work? Probably not. Do I have copies of CDs where I do not own the original? Yes, one CD where I have the LP and one where I don't (and both are of 30-year old music). Would I buy as many CDs if I couldn't make copies of them? No. Sometimes I wonder which planet the RIAA is on. (My $0.02) Bob -----Original Message----- From: pete(a)dunnington.u-net.com [mailto:pete@dunnington.u-net.com] Sent: Friday, December 13, 2002 2:29 PM To: cctalk(a)classiccmp.org Subject: Re: OT: Re: Interesting Tim O'Reilly article. On Dec 13, 11:12, David Woyciesjes wrote: > Sellam Ismail wrote: > I'm like Sellam here. I have bought quite a few CDs, based on hearing a > song or two from the album via Napster. > Granted, I'm one of those people who look for that album in the used > rack first, before resorting to a buying new copy. It is a form of > recycling; but I wonder what exactly do the record labels think of me > for that? > I also believe that new audio CDs are still overpriced. Doesn't stop me > from buying one, though, if I can't find a used copy. If *you* think they're overpriced... I just bought two today, for presents. UKP13.99 each, which is just over $22 according to the Universal Currency Converter. Yet when I look at my colleagues at work listening to CDs, I see they spend part of the time listening to MP3s, and about half (I guess) to CDs. Of the CDs, nearly all are original shop-bought, not CD-R copies. They have the technology, so that's not why they don't copy stuff. There's a difference in quality, and in reliability/robustness, and you don't get the sleeve notes and graphics with a copy. The students I see seem to do the same. I don't believe the hype or the wailing and moaning >from the music companies. -- Pete Peter Turnbull Network Manager University of York

23 years, 4 months

OT: Re: Interesting Tim O'Reilly article.

by pete＠dunnington.u-net.com

On Dec 13, 11:12, David Woyciesjes wrote: > Sellam Ismail wrote: > I'm like Sellam here. I have bought quite a few CDs, based on hearing a > song or two from the album via Napster. > Granted, I'm one of those people who look for that album in the used > rack first, before resorting to a buying new copy. It is a form of > recycling; but I wonder what exactly do the record labels think of me > for that? > I also believe that new audio CDs are still overpriced. Doesn't stop me > from buying one, though, if I can't find a used copy. If *you* think they're overpriced... I just bought two today, for presents. UKP13.99 each, which is just over $22 according to the Universal Currency Converter. Yet when I look at my colleagues at work listening to CDs, I see they spend part of the time listening to MP3s, and about half (I guess) to CDs. Of the CDs, nearly all are original shop-bought, not CD-R copies. They have the technology, so that's not why they don't copy stuff. There's a difference in quality, and in reliability/robustness, and you don't get the sleeve notes and graphics with a copy. The students I see seem to do the same. I don't believe the hype or the wailing and moaning >from the music companies. -- Pete Peter Turnbull Network Manager University of York

23 years, 4 months

Televideo 901 was Re: New finds this week / Cheap to a good home

by rigdonj＠cfl.rr.com

At 11:16 AM 12/13/02 -0500, Pat wrote: >I managed to get a few fun things to play with this week - courtesy of >Purdue University Salvage/Surplus > >** Finds ** > >Lear-Sigler AMD-3A+ **actually working** (compared to my ADM-5) $free Speaking of LS terminals. I spotted a Televideo 901 last week. It looked like a Lear Sigler ADM (something). Does anyone know if it was built by LS? Joe

23 years, 4 months

The Ne[w|utered] HP / Agilent

by glenslick＠hotmail.com

Their current 16700 series LA mainframes (I have one) still run HPUX 10.20 on a PA-RISC CPU with all of the network capabilities of HPUX. I think some things are disabled by default, but you can boot single user mode and reconfigure things if you really want to. I agree that I wouldn't want Windows 9x running on an instrument like this, but Windows 2000 might not be too bad, as Tek runs on some of their current LA mainframes. >From: "Eric Smith" <eric(a)brouhaha.com> >Reply-To: cctalk(a)classiccmp.org >To: <cctalk(a)classiccmp.org> >Subject: Re: The Ne[w|utered] HP (was: RE: The effects of employment) >Date: Thu, 12 Dec 2002 18:31:25 -0800 (PST) > >My biggest gripe with Agilent is that their recent instruments such >as the Infinium series oscilliscopes run Windows. I don't use the >things myself, but I've heard horror stories from friends using them. >It's a shame that they didn't use Linux, or xBSD. Some of their >earlier instruments such as logic analyzers actually acted as NFS >and X clients, but the networking capabilities of Windows are a huge >step backwards. _________________________________________________________________ Protect your PC - get McAfee.com VirusScan Online http://clinic.mcafee.com/clinic/ibuy/campaign.asp?cid=3963

23 years, 4 months

Interesting Tim O\'Reilly article.

by classiccmp＠crash.com

[ Trying to put some classiccmp spin on the discussion... ] > Imagine General Motors, Ford, Toyota or any other car maker > wanting a cut of the money if you sell your old car to some- > body else instead of just dropping it into the next landfill. This reminds me of my biggest complaint about several commercial Unix offerings in the early 90's - user licensing. "Excuse me, I can only have X users on my Vax/Alpha?" Alright, maybe some other non-Unix OSes as well ;^) The analogy was always to Ford/GM saying, "Yes, you bought our biggest van with the third row seat, but you may only use the the front two bucket seats until you pay us Y dollars per year." Definitely led me to move to systems that didn't have such silly encumbrances. --Steve.

23 years, 4 months

Fwd: Hermes 51

by jss＠subatomix.com

Please direct replies to Lynda, not me. ---------- Begin forwarded message ---------- From: Lynda Pieper <lcpieper(a)hotmail.com> To: cctalk-admin(a)classiccmp.org Date: Sunday, December 8, 2002, 4:19:41 PM Subject: Hermes 51 I came across your website looking for "Hermes 51", which is a 1984 dedicated word processor. Since your site is now under construction, I wanted to know if you know of anyone who would be interested in buying the Hermes 51. I have not used it since I got my 286 computer in 1987. Everything for the Hermes is intact, including diskettes. If you know of anyone or any place interested in this word processing, please let me know. The Hermes was an electronic typewriter with internal memory and an LED to show about 20 characters at a time as you typed, plus an external video unit (with about a 12" screen) which used the small diskettes for storage. I have ribbons, daisy-wheel fonts, diskettes, etc. It should still work... I used it for only three years on a part-time basis. Please e-mail me with a "yea" or a "nay". Thanks. L. Pieper lcpieper(a)hotmail.com ---------- End forwarded message ---------- -- Jeffrey Sharp

23 years, 4 months

Interesting Tim O'Reilly article.

by Robert_Feldman＠jdedwards.com

And, though the US carries a pretty big stick, the rest of the world doesn't necessarily follow the US direction on the DCMA and the new Mickey Mouse copyright laws. Bob -----Original Message----- From: John Allain [mailto:allain@panix.com] Sent: Friday, December 13, 2002 11:37 AM To: cctalk(a)classiccmp.org Subject: Re: Re: Interesting Tim O'Reilly article. > Reverse engineering itself is not a crime. Agree, but... The whole notion of what crimes are with a Software entity is too nebulous. That's why the the Son-of-a-Lawyer has made so much money testing the boundaries of Pseudo law, and winning. This is a new industry and things haven't totally jelled yet. John A.

23 years, 4 months

Interesting Tim O'Reilly article.

by Fred.van.Kempen＠microwalt.nl

> On Fri, 13 Dec 2002, Brian Chase wrote: > > > on his actions. Now, the MPAA folks say that reverse > engineering their > > lousy CSS encryption is a crime. I think that's absurd, > and I'm really > > surprised that /anyone/ on /this/ list would agree with the > idea that > > reverse engineering something is, in itself, a criminal act. > > I have to second that. Me too. Reverse engineering itsef is not a crime.. what you )can( do with the )results( _could_ be a crime. --fred

23 years, 4 months

GenRad tester

by Qstieee＠aol.com

I believe someone asked about this in the last few weeks, but I didn't save the message. E-mail trestivo(a)concentric.net, he services them. See www.tarinc.com

23 years, 4 months

WinPort LaserJet Accelerator Card

by dwoyciesjes＠comcast.net

I picked up one of these yesterday for $25. And it still has the original retail sticker, of $99.99 on it. :) Turns out, it is unused even! the two cards and 5 1/4 floppy envelopes are still sealed... Anyway, to my point. I plan on using it in the docking station of my Thinkpad 760EL (running Win98), plugged into a DecLaser 2100 plus. IIRC, the DecLaser 2100 is just a HP LaserJet II with different plastic body panels, right? I has a 16 bit ISA card to go in the PC, and an adapter card that goes in the Optional I/O slot of the printer. It also keeps the normal parallel printer cable in place, for regular operational mode. Now, the manual only mentions Win3.1; not even NT 3.5. Has anyone tried this under Win98? How about NT4? And how about sharing it over the network? Hopefully I'll get the time to set it up and try it today. First, I have to dig out that little Digital 486 I have sitting around to transfer the drivers to 3 1/2 floppy! Seeing the 5 1/4 floppy was a bit of a surprise... Thinking out loud... I wonder if I'll end up having to turn that desktop 486 into a Win3.11 print server? :) Hmmm, would Solaris or NetBSD know what to do with it? -- ---Dave Woyciesjes ---ICQ# 905818

23 years, 4 months

Value of VAX ?

by Fred.van.Kempen＠microwalt.nl

Hey All, Just a slightly offtopic one here. What should I be paying for a used VAX 4000, 128MB, with an extra 128MB as spare? Machine looks good, and comes with two BA440's (one with the machine, and the second one for extended storage.) Pse reply *off-list* - enough offtopic clutter as-is already :) Thanks, Fred

23 years, 4 months

Freeware for VAX!

by hansp＠aconit.org

I found this on a recent CUO/DECUS mailing: Freeware for Vax Computer Communications Limited (CCL) the UK developer of Electronic Document Distribution software for HP Open VMS, has announced the availability of a Freeware version of its software. The Freeware version is available to companies that are still using OPENVMS on the VAX hardware platform. The software allows data to be sent via Fax, Telex, E-mail (with Lotus Notes and Microsoft Exchange interfaces) EDI and Text messaging to Mobile Phones. Further information about their solution can be obtained from CCL's web site: www.ccl.co.uk

23 years, 4 months

Acquired a PDP11/44, but missing M7095

by dwightk.elvey＠amd.com

>From: ard(a)p850ug1.demon.co.uk > >> Jesus H Kraist!!!!! Zane, you need to stick with shit you know about, >> and leave the electrical advice to folks who understand the difference >> between voltage and current. >> >> >> DO NOT plug your 120v PDP11 into a 220V Dryer Outlet!!!!! >> >> DO NOT plug your 120v PDP11 into a 220V Dryer Outlet!!!!! > >I will agree with that, _but_ > >(1), IIRC the 11/44 has a handy switch on/in the PSU to select between >115V and 230V input. It would be easy to flip that. > >(2) I was under the impression that US dryers, while using 230V for the >heating elements, used 115V for the timer. And that US domestic mains was >a centre-tapped (The tap being called 'neutral') 230V supply. > >In which case, if there's a neutral feed to the dryer socket which can >carry the same current (20A) as the 2 live feeds (one from each side of >the mains), then you could run the 11/44 between one live feed and >neutral. This probably breaks code in a dozen places, but.... > Hi My drier has a three pin plug, Two hots and one ground, No Neutral! I would assume that if anyhting ran on 115, it would be through a transformer but I think the time is 230V as well. Dwight

23 years, 4 months

More dumb VAX 11/750 questions

by alanp＠snowmoose.com

Hi guys, Finding this list has encouraged me to try and get some stuff together on my VAX. Sorry for the extra traffic. Q1. Right now I have a UNIBUS expansion cabinet attached to the primary 11/750 cabinet. I would like to replace it with my TU80 (with a RA82 in the lower drive bay). Can I just move the UNIBUS cards that I want to keep to the primary UNIBUS and pull the DW750 from the CPU back plane and be good? The James Lothian FAQ mentions something about reconfiguring some jumpers if you install a DW750, so I would probably need to change them back if I remove it, right? Q2. Right now I have a DEUNA, UDA50/UDA52 and DHU11 in the primary UNIBUS with those bus continuity cards installed in the open bus slots. On the secondary UNIBUS, I have the TU80 controller, another DHU11 and a DMF32. Can I just pull the bus continuity cards from the primary UNIBUS and install the TU80 controller and DMF32 in those slots? Q3. Right now the memory slots have M8750s CJs in both end slots and 6 six National Semiconductor 753 1M boards in between. Does it have to be this way? I have two spare M8750s. Are there any advantages between the DEC memory boards and the NS boards? Q4. I have a floating point option board (L0001) that is supposedly intermittently bad. Anyone know what kinds of things fail on these boards? Q5. Should I use or not use some kind of contact cleaner on the board fingers and the sockets they go in? Thanks, alan

23 years, 4 months

BBC Acorn

by pete＠dunnington.u-net.com

On Dec 13, 0:57, Tony Duell wrote: > One you missed (I am not sure if you count it as 3rd party...) is the > IEEE-FS. It was used with the IEEE-488 interface (which, IIRC, was > technically a 3rd party product sold by Acorn [1]) and allowed you to > open 'files' to devices on the IEEE-488 bus, etc. Yes, it was sold by Acorn, and it was in the official price list. It was unusual in that it was sold both by Acorn and by the original devloper, Intelligent Interfaces. The manual says it was developed jointly, so I imagine that's why. The oldest price list I can lay my hands on quickly is January 1988, and it lists it at UKP325.00. > [1] Or at least that's what I was told when I asked a friend of mine who > worked at Acorn about getting a schematic for this interface. I then > found the schematics had been published in Wireless World... :-) -- Pete Peter Turnbull Network Manager University of York

23 years, 4 months

MicroVAX II

by Antonio.Carlini＠riverstonenet.com

>only the power harness. And assuming one couldn't find a replacement power harness for the bad >one, what would it take to modify/repair the bad one to make it safe to use? Is it just the matter >of replacing some of the existing wire with something of a heavier gauge? I believe the problem is that the wires are of differing lengths and hence resistance. Plus they were (or may have been) specced a tad to near the limit. The end result was that the longest wire (greatest resistance) heated up the most and eventually went phut, leaving the other five (or so) to go pop shortly thereafter. So heavier gauge and same length would seem to be required. OTOH if the problem was that bad (none of mine in the lab ever exhibited any pyrotechnic tendencies) would it not have corrected itself by now :-) Antonio

23 years, 4 months

SCSI CDROM 'juke box' setup

by donm＠cts.com

A while back, I acquired a 7-disk NEC MultiSpin 2Xc drive which uses a SCSI interface. With no particular difficulty, I installed the WD SCSI card and the drive, the CONFIG.SYS and AUTOEXEC.BAT patches and quickly had access to the drive. Well, I had access to the first disk in the drive. The existence of the remaining six were not acknowledged! The WD diagnostic program sees all seven, so I tend to doubt that it is a SCSI problem, but nothing that I have done relative to MSCDEX has had any useful effects either. For perspective, this testing is being done on a Pentium II 133MHz equipped motherboard with 16Mb memory running PCDOS 6.3. I have yet to try it with W98. Can anyone offer any hints, kinks, experience, or clues of any variety as to how to access the remaining 86% of this 'juke box'? Thanks! - don

23 years, 4 months

The Ne[w|utered] HP (was: RE: The effects of employment)

by rigdonj＠cfl.rr.com

At 03:35 PM 12/12/02 +0100, Fred wrote: >Hi all, > >What stuns me about this what seems to be a national effort to wipe >out existing knowledge and experience in the various U.S. companies >trying to clean up their EOY numbers, is that they truly dont KNOW >what they're doing. I knew that when they appointed a woman CEO that knew NOTHING about computers or test equipment, the two items that HP was built on and reached major success with. It was again confirmed when they threw away the HP name (and outstanding reputation) and renamed it Agilent. Joe

23 years, 4 months

BBC Acorn

by pete＠dunnington.u-net.com

On Dec 12, 7:40, Joe wrote: > It does appear to be a B. It has two rows of (mumble)16 memory chips so it has 32k of RAM. It probably is a B if that's the case (and the part number certainly is a "B" part number) but just having the RAM doesn't make it so. The chips are 4116s, BTW. As Tony said, there are lots of differences between an A and a B, but all the upgrades are/were available and there is no difference between an upgraded A and a B (except perhaps the date codes on some chips, how many are socketed, and maybe a little flux residue on the board). I thought I had a document listing the exact differences between UK and US versions, but I can't find it :-( However, the differences are small: different MOS (mainly video timings to be programmed into the CRTC), different colour crystal, different BASIC ROM (American spellings added, version number changed from II to III). IIRC the US version also had Econet and speech synthesis fitted (otions on the UK version). It didn't sell very well, and eventually a lot were re-imported to the UK becasue there was a boom in demand around 1986-87, which rather surprised Acornm, as they'd had two successor models since the original Model B in 1981! > What is "DFS OS"? Something is wriong if it says "DFS OS", I think. See below. DFS = Disc Filing System ("disc" has a "c" in English :-)). A single-density dis[ck] filing system, with a fairly simple flat directory structure. It can handle two 5.25" floppies, which may be any mixture of double- or single-sided, 40- or 80-track, so long as they have a standard SA400-type interface. Capacities are 200K for 40-track discs, 400K for 80-track. The two sides are treated as separate disks (so Drive 0 and Drive 2 are opposite sides of the same physical unit, and 1 and for the other unit). > I was surprised to find that it uses an intel 8271 for floppy drive controller. It's based on an earlier Acorn design. It's possible to replace the 8271 and some parts with others, plus a daughterboard carrying a 1770. You need the "1770 DFS" to drive it, still single density (in fact, compatible in almost every way) but you can then also add the ADFS (Advanced Disc Filing System) ROM to get double-density and a fully hierarchical directory structure. Capacities range from 160K (40-track, SS) to 640K (DS 80-track), called "S" (small), "M" (medium), "L" (large). As you may have guessed by now, if you didn't already know, many parts of the MOS are modular, and it's possible to add many other ROMs with languages, service utilities, and filing systems. FS's I can think of off the top of my head include TAPE (cassette filing system, built-in), RFS (ROM Filing System, also built in), DFS (you've met), ADFS (see above), TFS (Telesoftware, with a teletext adaptor), NFS (Econet networking), DNFS (combined DFS, NFS, and 2nd Processor handler), VFS (Video Filing System, of Domesday fame), "Advanced" versions of some of these, and various third-party equivalents. > It powered up up but isn't recognizing any keys except the BREAK key. I ran it for over an hour then one of the rectangular tantalum filter caps in the PSU blew. Fixing the PSU shouldn't be a problem. Does anyone know what they use for a keyboard interface (if it even uses one)? or if there's any schematics posted anywhere for it? You want to look at a couple of sites in particular, starting with The BBC Lives! at http://www.nvg.ntnu.no/bbc/ and The BBC Documentation Project at http://www.bbcdocs.com/ There you'll find many things, including the Service Manuals (look under "Essentials"), which include the schematics. Also 8BS Software at http://8bs.com , where you'll find a nicely annotated set of pictures of the BBC B motherboard (http://8bs.com/inbbc.htm). Chris Richardson at 8BS lives not far from me, and he's scanned a lot of my manuals and contributed them to The BBC Documentation Project. When you power up a working Beeb, it should make a double "beep" and then display something like BBC Microcomputer 32K Acorn DFS BASIC > If you get nothing, check power. If you get a continuous tone and not much more, or just get a flashing cursor at top left, check the keyboard cable, IC3, and other keyboard-related stuff. The way the keyboard works is quite neat. Like almost everything on a Beeb, it's interrupt-driven (unlike Apples and PETs, which are much slower -- even allowing for clock speed differences -- becasue they use polling loops). I wrote the following to explain it on a BBC mailing list recently, when someone had a faulty one. This particular fault was heat-related, hence the notes at the end; note that the most common fault is a broken or mis-fitted 17-way ribbon cable between keyboard and motherboard or a cracked track near a key: A 74LS161 (or 74163, they're interchangable for this purpose) 4-bit pre-loadable counter is clocked at 1MHz, and its outputs drive a 7445 (or 74145, again they're interchangable for this purpose) one-of-ten decoder. For each state "0" to "9" generated by the counter, one of the open-collector outputs of the 7445 is pulled low, and the corresponding keyboard column goes low. If a key in that column is pressed at the time, one of the row inputs of a 74LS30 is also pulled low, which signals to the system VIA on its CA2 handshake pin, and generates an interrupt. When the MOS services the interrupt, it uses PA0-PA3 to drive the 74LS161 like a latch, and tests each column in turn. For each column, it also selects each row in turn. Each row is connected to one input of a 72LS251 multiplexer, and by using PA4-PA6 to address the MUX, the MUX output, which is conected to PA7, can be sampled. When the MUX output is low, you've found the row and column of the key that was pressed to generate the interrupt. The most likely fault is a cracked track near the counter or MUX; I've seen similar situations where a crack right beside an IC becomes heat sensitive (when it warms up, the metal expands and -- counterintuitively -- widens the crack. Second most likely is the chip itself. If all the keys in one column are faulty, suspect the decoder (7445). If all the keys in several columns are bad, suspect the counter (74LS161). If some keys in a column are good but some are bad, but all the keys in a row are bad, suspect the MUX (74LS251). If it's just a mixture, suspect the VIA (which is usually socketed, so easy to swap with the user VIA). -- Pete Peter Turnbull Network Manager University of York

23 years, 4 months

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