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Report on vintage "Programmer Electronnic Control" alias "RAF Tornado Computer"

by roger.holmes＠microspot.co.uk

>> Then I looked at the pictures, and saw it was made by my old >> employers, Marconi Avionics who took over Elliott Brothers, and >> continued to make 920 series machines. I think there were 12 bit >> versions made by one of the divisions, though I am surprised they >> were still making them in the 1980s. > Yes, the unit was made after 1986 I think. One quy in the > rec.aviation.military claimed, that the box might be from > early tornados as I mentioned in my original posting. I do > not know how long development of such an aircraft takes but > the first take-off was in 1974 I think, so this would match > the design of this box wuite well - what do you think? Aircraft development takes a long long time. To make it worthwhile the aircraft has a long service life. Whilst the computers are bullet proof in an office/home, the temperature extremes, vibration, high G forces etc in service means that many failures occur and PCBs could be replaced many times over the years, so do not pay too much notice of the dates on components of the boards currently installed. There were at least four 12 bit versions, and one 13 bit apparently. Then 12 bit models were the 902, 102C, ARCH 105 and Minim or 12/12. > >> One part of Elliott Brothers became GEC Computers (based in >> Borehamwood). > Yes, that matches - the core memory module already has the > label GEC. So this is (as I suspected) older than the CPU and > taken maybe from a different design?! You have it the wrong way around. The GEC name replaced the Marconi name, which had earlier replaced Elliott. Core memory was very convenient for military applications and was in use long after it was replaced in commercial applications. Think of a missile or torpedo held in stock for many years, stick a power plug into it and program the target, pull out the plug and then launch it. Only then does the internal power supply come up, the processor boots up and does its thing. > >> One of your labels is from Airborne Displays Division based at the >> same Rochester site as I worked. This was also part of Marconi >> Avionics, and the company later changed its name to GEC Avionics. I >> worked on compilers, linkers and other utility software for the 18 >> bit 920s before moving on to the Zilog Z8001. > Hey, than you are a valuable expert on these - do you have > got any source of intormation about the 920s? Not directly but I may be able to help. > >> Erik, could you tell me if the instruction code is anything like >> this: >> 0 Load B (indexing) register and the Q register (shift extension) > > RIGHT > > >> 1 Add to accumulator > > RIGHT > > >> 2 Negate and add to accumulator > > RIGHT > > >> 3 Store the Q register > > RIGHT > > >> 4 Load accumulator > > RIGHT > > >> 5 Store accumulator > > RIGHT > > >> 6 And to accumulator > > RIGHT > > >> 7 Jump if zero > > RIGHT > > >> 8 Jump > > RIGHT > > >> 9 Jump if negative > > RIGHT - all three jumps are relative ones On the 18 bit machines these were relative to the start of the 8k memory module the instruction was in. An interesting modification. > > >> 10 Increment > > RIGHT > > >> 11 Store program counter (for function return) > > SIMILAR - This stores PC and then does a > table jump On the 18 bit machines, it actually stored the program counter + 1 and the following instruction was either an 8 or a "/8", i.e. 24. > > >> 12 Multiply > > RIGHT, unsigned multiplication This should multiply the signed accumulator and the signed memory operand giving a double length result in the A and Q registers. > > >> 13 Divide > > HMMM, the command takes very long but the results are > very strange. I thought it might be some type of > random number generation by an irreducible polynomal, > but it is definitively not Divide. Maybe here is something > different or wrong with the microcode. This divides a signed DOUBLE LENGTH number in the A and Q registers by a signed memory operand. IIRC the A register gets the result and the Q register the remainder. > >> 14 Shift > > In PART: Here exist many subgroups of commands including > shift left/right. Also the Q as you call it can be transferred > to Accu and vice versa. There als is a MTA (MoveToAccu as I call it) > which is a two-word instruction (most others are one-word) and > transfers the word following this command into Accu. About > 16 bit patterns have (at least to me now) the same meaning in > this segment. Shifting by the entire word length does transfer Q to A or A to Q (but the data disappears from the source). A load immediate instruction would have been very handy. There was also a block move instruction here in the 18 bit machines. Maybe some of the special 15 orders were encoded in the 14 order on the 12 bit machines with only 256 numbers available compared with 8k on the 18 bitters. > > >> 15 Input/Output and special (like interrupt return) > > Yes, in part as well. Commands for sending and receiving > via the serial links I found here. > >> 16 to 31, as above but indexed by B register. > > NOPE - The box is 12-bit and does not have got this block. > EVERYTHING is done via the index register I as I called it. Do you mean you cannot turn the B-register modification off? Does it get cleared automatically somehow? > > > > So > > ####### > # # # ##### ###### # # ## > # # # # # # # # # # > ##### # # # # ##### #### # # > # # # ##### # # # ###### > # # # # # # # # # # > ####### #### # # ###### # # # # Eh? > > the box is a 12-bit version of the Elliot series of Computer. > Lot of work for rediscovering the instruction set of the 920 > Elliot... > > Roger, do you have got any detailed information on these > you are willing to share with me! I am familar with the above > mentioned instruction set, but some details are still open and > perhaps studying the Elliot would help to solve the remaining > problems??!?!?!! I am willing to try. By the way, there are two 't's in Elliott. > >> In early versions of the 920, the B and Q registers were the same >> register and it and the program counter were held in memory. There > > In this box the registers are stored in "batteries" of 74xxx flip > flops on the processor boards. On the later 920s, the current interrupt levels B register and sequence control register (i.e. program counter) were held in real registers but the other interrupt ones were held in memory. There was extra circuitry to make it so that writing to the current level's B register address actually got trapped and also modified the real register. >> were four levels of interrupt and a set of these registers for each, >> held in location 0 to 7. The high end of memory held a paper tape >> bootstrap, in later versions, this was just copied into core when the >> machine was initialised. > Interesting. The Programmer Electronic Control starts execution > at 0x0a0 after reset. Could it be that there is a value of 0x0A0 at location 0? > But of course the application was different > and the operation software was completely loaded via the big plug > boefore operation. I suspect the big plug is for the OMP (Operator's Monitor Panel), and yes the program would be loaded via this once, probably in the factory or at a maintenance depot, and the machine would probably be rebooted many times afterwards. > >> If this indeed a military machine, you can be sure the memory was >> erase by flipping every bit backwards and forwards several hundred >> times to remove any trace magnetism before it was released from >> the RAF. > Yes you are probably right. I thought just in case there are some > fragements inside it would have been interesting to study them > in order to learn about the instruction set. > > I am sure the unit supports interrupts (one for each serial > port (panavia link I think) and maybe there is an additional > for the timer. This timer has a reload register and > thus can be programmed to arbitrary intervals (12bit, running > at 2MHz). But up to now I was not able to read or write it > nor occured an interrupt. Here studying the Elliot would > really be inspiring - I am very sure that they reused the > know how here as well... The 920 was unusual in that it booted into the highest level interrupt, level 1, so no interrupts will be serviced until you go down an interrupt level or two or three. The 15 order is coded thus: 15 0 to 2047 Input 15 2048 Shift A register left 7 places and OR in a character from the paper tape reader (via OMP) 15 2052 (IIRC) Wait until character pressed on teletype and read into A register (via OMP) 15 4096 to 6143 Output 15 6144 Output character to paper tape punch (via OMP) 15 6148 Output character to teletype (via OMP) if I remember correctly 15 7168 Terminate current program level i.e. return from interrupt 15 7169 Test if standardised IIRC, skip the next instruction if the accumulator is zero or top two bits are different 15 7170 Increment B and skip the next instruction if bottom 13 bits are zero 15 7171 Read the value of the control keys on the OMP 15 7172 Move l.s. 17 bits of A to the m.s. 17 bits of Q. Bottom bit of Q is zeroed 15 7173 Move m.s. 17 bits of Q to l.s. 17 bits of A. Top bit of A is zeroed 15 7174 Move A to B 15 7175 Move B to A 15 7176 Set relative addressing mode 15 7177 Set absolute addressing mode In relative mode, all addresses are relative to the start of the 8k block of memory the instruction is in. In absolute mode (the default), 7,8 and 9 orders are still relative but in all others the address is absolute, so that only the bottom 8k of memory is accessible without using B modifiers. Roger Holmes.

19 years, 3 months

XMI goodies?

by doc＠mdrconsult.com

Is there any interest here in DEC XMI gear? Preferably cash or trade interest.... ;) I have several rackmount XMI enclosures, a couple of CI and a *bunch* of SCSI and ethernet boards with cab kits. They're about to go on eBay, but I thought I'd check here to see if anyone's looking. Oh, yeah, I also have 5 or 6 star couplers and a bunch of Big Blue CI cable, and a couple of HS<mumble> CI-SCSI adapters *without* their flash cards. For that matter, I have 2 rackmount DEC7000 cabinets I'd like to see disappear. One is the bare cabinet, the other has 2 procs and the laserbus-XMI adapter intact. I'm supremely uninterested in crating or palletizing the enclosures, so you'll need either to arrange that yourself or prepare to be extorted. :) Reply off-list if interested. I'll be making a more specific inventory this weekend. Doc

19 years, 3 months

VT-180 (Robin) EPROM images?

by bob＠jfcl.com

Does anybody have images of the v2.1 Z-80 firmware for the VT-180 (aka Robin) ? At least, I think 2.1 was the last version ever released. They should be DEC part numbers 23-017E3-00 and 23-021E3-00. Thanks, Bob Armstrong

19 years, 3 months

HP 400 series

by teoz＠neo.rr.com

Anybody know much about the HP 400 series of 68K Unix machines? Is the OS for this system still available, also can you rig a VGA monitor to one?

19 years, 3 months

VCF East 4.0 website now up

by evan＠snarc.net

Hi all, The VCF East 4.0 web site at www.vintage.org is now ready for use. The event, in case you forgot, is TWO days this year -- June 9-10. Exhibit booths and vendor booths cost the same. (At past VCFs it cost a lot more for a vendor booth than for an exhibit booth.) The single-booth fees are: $15 for paid MARCH members ($5 cheaper than last year) $25 for everyone else Discounts may be available for people who reserve multiple booths. We'll have almost twice as much physical space as last year, so we want as many exhibitors as possible. We'll accept vendors but that really is not the focus. PLEASE SIGN UP EARLY. AS EARLY AS POSSIBLE. Even if you only have a general idea so far of your exhibit topic, that's fine. Go ahead and sign up. It makes life much easier for us in planning and marketing the event. If everyone waits until the last minute, then the public will go to the VCF web site and see what appears to be very little participation, and decide not to attend. Conversely, if people sign up early, it builds excitement for the event. - Evan

19 years, 3 months

11/45 revisited

by aek＠bitsavers.org

A set of 11/45 engineering drawing scans are up now under http://bitsavers.org/pdf/dec/pdp11/1145

19 years, 3 months

Modern Marvels: Computers

by legalize＠xmission.com

I bought this from dvdplanet the other day (good deal: $15) and watched it recently. They seemed to skip the entire minicomputer/workstation phase and jumped straight from mainframes to the personal computer. What was interesting though is the collection of footage that they used throughout. I spotted what looked like footage of an HP terminal factory, manufacturing 2621's. On the shelves in the background were 2648 style cabinets. It was a brief clip, but I felt "cool" knowing that I was one of the few people who would recognize the equipment! -- "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/>

19 years, 3 months

Memory refresher

by cclist＠sydex.com

I'm hoping someone out there can help me remember. I can dig through my hellbox and hook up a drive and figure it out, but I'd just as soon hear it from someone with a better memory. It's this: The old Sony SS 40-cylinder 3.5" floppy drives--was cylinder 0 located an additional step outwards from where modern 3.5" drives put cylinder 0? I can't remember for sure--it's a sign of age. Cheers, Chuck

19 years, 3 months

raster laser?

by dgriffi＠cs.csubak.edu

Somehow I got subscribed to an optics catalog. This got me to thinking. How hard would it be to cause a laser beam to sweep with the speed and accuracy to be a substitute for a CRT? The upshot? Take an old terminal with nasty screen burn. Cut off the gun end of the bottle, clean off the old phosphor. Apply new phosphor of some kind, then mount the laser rasteriser where the old gun was. Projecting raster images on the side of a building would be fun too. -- David Griffith dgriffi at cs.csubak.edu A: Because it fouls the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail?

19 years, 3 months

11/45 revisited

by jwest＠ezwind.net

Told ya'll I was going to dig back in to that 11/45 restoration project :) Got the workroom cleaned up enough to actually have room to work on the thing. Stripped it down to the very most basic configuration possible (including getting rid of the 9312 for a 930, etc.). Barebones. No cards in SPC slots except grants. Known good 16K of core and then a base processor set (without segmentation and without FP). Turned on the bottom 742, then the top one... fans all come on but nothing on the front panel at all. Checked the obvious front panel keylock, it wasn't off. Time to check voltages & ripple on the backplane. E02B2 is at 0.55v, indicating the H745 in slot E is officially a problem child. E15A1 is at 0.95v and E01B1 is at 0.05v, so the +15v regulator built into the top H742a is suspect. Noted that the small fan on the top of the top H742a isn't turning so likely the regulator is well-done. The test points on the backplane for regulators B, C & D are ok, as is the -15v from the bottom H742a. Time to get the H742a docs from bitsavers :) Jay West

19 years, 3 months

An old email Atari

by Ming_Mae＠hotmail.com

"the resident Atari Maniac with a side fetish for Mindset and Corvus systems, now playing with a VAX.....Curt" Just a blind shot in the dark trying to find someone who knows about Corvus Systems and Atari 8-bits> We had heard one time that Ataris had beenn hooked to a Corvus system and were wondering if you had any info. Thank you for your time -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.446 / Virus Database: 268.18.7/710 - Release Date: 3/4/2007 1:58 PM

19 years, 3 months

raster laser? - Ameteur Scientist

by rdawson16＠hotmail.com

They are on the web if you look hard enough. Unfortunatley the whole collection is a mess. They should have distributed it in PDFs of the original pages to maintain the feeling of the originals. But NO, they html the whole thing poorly, and the original art is low res too. I am fortunate to have the university nearby, and there is nothing like flipping through old SciAm binders. The computer ads from the 50s-60s are incredible. where's my flying car? I want the future as depicted in the magazine. If you can have access to these, also notice the employment ads. Everybody was in the exciting field of computers, a rocket scientist, or electronics engineer. Dont forget to check out the Amateur Scientist book too. There is a relay based tic-tac toe machine, farmer fox, goose computer too. It is a collection of some of the best articles. In the magazine, Marvin Gardner's Mathematical puzzles column too! lots of binary and computer algorithms foretelling the future are in there. I grew up in the NASA environment. As A kid I got to go in the clean rooms and see the spacecraft. Then they brought me into the computer room to play tic tac-toe at the console. I want to go back... Or surround my basement with vaccum column tape drives and a console of switches and blinkinlights. Nevermind its a PC runing the show, but its running a s/360 emulator.. Grab your pocket protectors and slide rules, come over to my house! Randy >From: Bob Rosenbloom <bobalan at sbcglobal.net> >Reply-To: "General Discussion: On-Topic and Off-Topic >Posts"<cctalk at classiccmp.org> >To: General Discussion: On-Topic and Off-Topic Posts ><cctalk at classiccmp.org> >Subject: Re: raster laser? - Ameteur Scientist >Date: Sat, 10 Mar 2007 05:12:33 -0800 > > > >Dave McGuire wrote: >>> >>>Does anyone on the list have this collection (SciAm Amateur Scientist >>>columns on CD-ROM)? >> >> I have them...I ordered them the day they were announced. >> >> -Dave >> >>--Dave McGuire >>Port Charlotte, FL >> >They are available on ePay for $24.00 > >Bob _________________________________________________________________ Find what you need at prices you?ll love. Compare products and save at MSN? Shopping. http://shopping.msn.com/default/shp/?ptnrid=37,ptnrdata=24102&tcode=T001MSN…

19 years, 3 months

DWBUA fun (was Re: Turning a VAX 11/750 into a workstation)

by ethan.dicks＠gmail.com

On 3/10/07, Sridhar Ayengar <ploopster at gmail.com> wrote: > Ethan Dicks wrote: > >> > I think a 11/750 makes a fine single-user VMS "workstation" ;-) > >> > >> Never trust a workstation that couldn't roll over you and smash you flat? > > > > I almost had an 11/750 land on me, but I was able to coax it out of > > the side door of a Chevy Astro mini-Van (alone) without getting > > squished or pinched. That was a fun experience. > > I once (with the help of a bunch of other people) was attempting to > unload a DECsystem 5810... > It landed on me as I was kneeling down. I caught it. I think I've heard people reference this incident on the list. I didn't know it was quite as spectactular as all of that - sounds like a combination of luck and quick action on the part of all present. > > Thinking about the whole "11/750 workstation" concept - I wonder if > > one could take a qbus mono framebuffer and hang it off of some flavor > > of Qniverter? > I once asked a question as to whether it would be possible to build a > VAX 6000-based workstation by hanging a Qbus framebuffer from a Unibux > slot hooked to a VAXBI bridge in a VAXBI slot in a secondary BI cage > hooked to a VAX 6000 through an XMI->VAXBI bridge. The consensus was > that it probably wouldn't work. 8-) Hmm... I have an 8300 in the basement with a non-working DWBUA (it used to work, about 13 years ago but that was before the machine got moved). My recollection of it was that (when it was working), the DWBUA was ok in a native VAXBI environment like the 82xx/83xx, but that when you started stacking bus converter on bus converter, it didn't take much to get things to the point of violating timing maximums on certain things. We had a problem with a Qbus COMBOARD being stuck in the same Qbus as a TLZ04 controller on an early model VAX 4000 since the CPU bus _wasn't_ Qbus, and there were enough subtle changes that hardware bus timeouts came into play, especially when the TLZ04 controller "went away" for a bit - I think officially, the timeouts were too stringent, but had never been a problem up to that model of VAX. I have to seriously wonder if you could get traffic from the Qbus, over the Q/Univerter, over the DWBUA over the XMI-BI bridge (forget the model #) before something timed out somewhere. No reason not to attempt it, but if it doesn't work the first time, the chain might just be too much to handle. -ethan P.S. - the problem I'm now having with my DWBUA might be a wonky UET (Unibus Exerciser/Terminator). The UET has to work perfectly and respond correctly when the DWBUA talks to it, or the DWBUA fails self-test. Could be cables, could be bad components, or could just be the phase of the moon. Either way, I installed a DWBUA correctly once, and now it appears to have been a fluke. It hasn't worked right since I moved it. :-( I have the docs, and according to the various device status registers, it acts like the DWBUA isn't seeing the right things from the UET. *slaps forehead* I have just the thing to check it out - a not-yet-assembled bare-board UA-11. I think assembling that just moved up the priority chain to sometime in the first 1/2 of this year!

19 years, 3 months

Report on vintage "Programmer Electronnic Control" alias "RAF Tornado Computer"

by Arno_1983＠gmx.de

Erik Baigar <erik at baigar.de> wrote: > Beginning of 2005 I got this small airborne computer via eBay and > I bought it mainly because of the 96k of core memory inside. Those > days some of these have been sold by ABEX (...) (Not directly related to your current project, but I immediately thought of it when I read "Tornado" - because I saw the Moving Map Display there - and noticed you're also from Germany) I assume you're aware of the massive amounts of aeronautic, military and electronic stuff www.helmut-singer.de (in or near Aachen) has to offer? Yours sincerely, -- Arno Kletzander Stud. Hilfskraft Informatik Sammlung Erlangen www.iser.uni-erlangen.de "Feel free" - 10 GB Mailbox, 100 FreeSMS/Monat ... Jetzt GMX TopMail testen: www.gmx.net/de/go/mailfooter/topmail-out

19 years, 3 months

CompuColor II ends...

by legalize＠xmission.com

Five bids and it closed at $1,124.00 That's out of my budget, whew. -- "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/>

19 years, 3 months

Report on vintage "Programmer Electronnic Control" alias "RAF Tornado Computer"

by roger.holmes＠microspot.co.uk

Erik, well done with the reverse engineering. I read your description of this computer with a strange feeling. I did not recognise it having 12 bits but everything else seemed very reminiscent of the Elliott 920 series. Then I looked at the pictures, and saw it was made by my old employers, Marconi Avionics who took over Elliott Brothers, and continued to make 920 series machines. I think there were 12 bit versions made by one of the divisions, though I am surprised they were still making them in the 1980s. One part of Elliott Brothers became GEC Computers (based in Borehamwood). One of your labels is from Airborne Displays Division based at the same Rochester site as I worked. This was also part of Marconi Avionics, and the company later changed its name to GEC Avionics. I worked on compilers, linkers and other utility software for the 18 bit 920s before moving on to the Zilog Z8001. Erik, could you tell me if the instruction code is anything like this: 0 Load B (indexing) register and the Q register (shift extension) 1 Add to accumulator 2 Negate and add to accumulator 3 Store the Q register 4 Load accumulator 5 Store accumulator 6 And to accumulator 7 Jump if zero 8 Jump 9 Jump if negative 10 Increment 11 Store program counter (for function return) 12 Multiply 13 Divide 14 Shift 15 Input/Output and special (like interrupt return) 16 to 31, as above but indexed by B register. In early versions of the 920, the B and Q registers were the same register and it and the program counter were held in memory. There were four levels of interrupt and a set of these registers for each, held in location 0 to 7. The high end of memory held a paper tape bootstrap, in later versions, this was just copied into core when the machine was initialised. If this indeed a military machine, you can be sure the memory was erase by flipping every bit backwards and forwards several hundred times to remove any trace magnetism before it was released from the RAF.

19 years, 3 months

Shameless Plug - 74xxxx series ICs

by trag＠io.com

>Date: Fri, 09 Mar 2007 14:40:11 -0600 >From: Jules Richardson <julesrichardsonuk at yahoo.co.uk> >Subject: Re: Shameless Plug - 74xxxx series ICs >To: General Discussion: On-Topic and Off-Topic Posts > <cctalk at classiccmp.org> >Message-ID: <45F1C62B.5000107 at yahoo.co.uk> >Content-Type: text/plain; charset=ISO-8859-15; format=flowed > >Doc Shipley wrote: >> I was up there yesterday and they have literally >> 50-60 feet of 6' shelves, nothing but 74xxxx ICs. >Seriously though, thanks for letting us know - personally I'd rather deal with >people that someone knows personally than some random ebay auction etc. MC Howard is about a mile from my house. I've shopped there for years. The only bad thing I can dredge up to say about them is that prices may vary wildly. Sometimes they charged me $.50 to program a handful of EPROMs, other times it was closer to a dollar or two. I've had many happy shopping hours there. There. Now someone who has personally dealt with them has recommended them. :-) I would have mentioned them myself, but it just never occurred to me that they were that rare/sought-after/valuable. I guess one takes the familiar for granted. Bob, my favorite sales person there, retired last year, but the other folks seem nice enough. I was used to Bob. All the times I've been there, they've never had any WD92C32s. I'm still looking for those at something close to $1 each. I've found folks who'll sell them at $5 each. I did find a handful of 92C16s at Howard's. Found some 68882s there, one at 50 MHz once. They still have a few at 16 MHz. I never found any 53C80s there, but I've found some 85C30s. They have a book shelf of old datasheet books for browsing and Bob used to make me photocopies if I found a chip that interested me. They also have a large assortment of housings and plugs and receptacles and sockets and such. Handy to have nearby when you're trying to get things to mate. Jeff Walther

19 years, 3 months

VMS for MicroVAX II/III (was Re: Value of a PDP/8?)

by ethan.dicks＠gmail.com

On 3/10/07, Zane H. Healy <healyzh at aracnet.com> wrote: > At 12:32 AM -0500 3/10/07, Ethan Dicks wrote: > >Did anyone on the list ever get that uVAX2000 SCSI mod working? > > All mine can do (or at least could in the late 90's) is format > drives. The memory is bad, but I could still use it as a formatter. My memory of things was that you first had to swap out the ROMs, then hang both a SCSI disk _and_ an RD disk off of the machine, _then_ patch a driver for the SCSI drive, then one could restore a saveset onto the SCSI disk and stop using the RD disk. Kind of a chicken-and-the-egg issue, but not insurmountable - just tedious. > Somehow I think it is easier, and likely cheaper to simply get a > better VAXstation, or an Alpha. Might not be as much fun, but I like > my VMS faster! :^) True enough, but at the time I was fiddling with all of this, I _had_ the uVAX 2000, and RD54s were $800-$1000 each while SCSI disks double that size were free or nearly so. SCSI-based VAXstations were nowhere close to free at the time, and I think a "noname" AT-sized Alpha motherboard was about $50-$100 w/0MB RAM. Given the hardware environment of the time, what I was doing made some modicum of sense. Now, it'd be just for the exercise of doing it, especially since if I _really_ just want to run VMS software and don't care about fiddling about with ancient disks and slow processors, I can throw a copy of VMS up on simh and get "real" work done (and given that my previous job was as a(n Open) VMS Administrator, I'm not that long out of using VMS 8-10 hours per day). Lately, though, I spend more time per month running simulated TOPS-20 than any flavor of VMS. Gotta finish ordering parts for that PANDA display so I can show it off. -ethan

19 years, 3 months

Value of a PDP/8?

by blstuart＠bellsouth.net

> I feel the need to ask - what is it that makes DEC stuff so popular and > collectible, versus other machines of the same time period? Generally they're > equally as interesting, and often more so (IMHO) due to all the quirks and > design differences versus the more mainstream DEC stuff. > > So... why? More of a community? Better documentation? Better hardware or > software availability? What do collectors *do* with their running DEC systems > anyway? I can't speak for everyone, but I can cite several reasons why I'm always more conscious of picking them up: - Early exposure: A lot of us used DEC systems in college. If we've stuck with the field, we probably have good memories of that time, and when you start getting to a certain point, the nostalgia connecting you back to a happier time is worth a few bucks. - Availability: While we'd all love to get our hands on a straight-8 or a PDP-7, there are certainly a number of models that are quite plentiful. So newcomers to the hobby can get their feet wet with with something outside the 8-bit world pretty easily. - Available software: Partly because of the availiability of the hardware, there's a lot of software out there. So when you get one up and running, you generally can do more than look at the blinkin' lights (though that's worthwhile in itself--much more soothing that a lot of other things). - Company history: The history of the company is long enough to be rich and short enough to be an object lesson. Because of that, the machines are connected with an important element of the overall history of the comuter industry. - Interesting machines: As you pointed out, there're often quite interesting machines. There's a good collection of documentation out there both in terms of details of specific models and in terms of the evolution of the families. - Connection to other history: Because they were so widely deployed, they're associated with a number of other historic bits of computing history. UNIX may be the most obvious example. Anyway, those are a few that come to mind at the moment. BLS

19 years, 3 months

Report on vintage "Programmer Electronnic Control" alias "RAF Tornado Computer"

by erik＠baigar.de

Dear vintage computing fans, in this posting I want to report the community on the restoration and reverse-engineering project I did over the last two years as a hobby. Maybe someone is interested in this or even has valuable information. http://www.baigar.de/TornadoComputerUnit/p8172677.jpg Beginning of 2005 I got this small airborne computer via eBay and I bought it mainly because of the 96k of core memory inside. Those days some of these have been sold by ABEX and it is still on their web page: http://www.abex.co.uk/sales/electronic/other/programmer/item.htm But they do not have them any more :-( :-( :-( (see below) In this forum William Maddox mentioned an eBay auction regarding one of these in his Nov/17/2003s posting "Latest EBay finds, including a real museum piece". After getting the unit I disassembled it and noticed that this must be a complete computer (size a little bigger than a shoe box) and I tried to collect information. But as expected no one was able supply significant information so I started PHASE0 (January 2005): Inspecting of all PCBs I drew basic wiring schemes and located the major parts of the system as timing generation, core logic, core drivers, microcode, ALU and so on. It became clear: THIS IS A 12-BIT MACHINE. The number of connectors of the box is limited (one for power, 5 plugs connecting to some kind of serial differential links and only one very big 135-pin beast). Since the big plug was the only one equipted with a protection cover I got the hope, that everything neccessary to operate the unit is within the one box I have got and not distributed over more devices. http://www.baigar.de/TornadoComputerUnit/Connectors.jpg Here I made the decision to continue reverse-engineering with the goal to make the unit OPERATIONAL. PHASE1 (March 2005): I put the core memory aside and investigated the power supply. Since I do not have got the 100V-tree phase AC of some weired frequency, this small switch mode power supply seems to quire, I figured out what voltages this generates and supplied them from external supplies (5V, 8A; -5V, +12V and variable voltage for core). I also located the "power good" signal and applied this, too. See pictures: http://www.baigar.de/TornadoComputerUnit/SupplyWithSubAssembly.jpg http://www.baigar.de/TornadoComputerUnit/SupplyBackplane.jpg http://www.baigar.de/TornadoComputerUnit/PowerSuppSubAssy1.jpg Now I was able to supply power and observed with the oscilloscope that there is activity. Now I thoroughly examined the core section until I had a good idea how it works, leading to PHASE2 (April 2005): supplying data to the data lines by using a 12-bit DIP-switch. This allowed me to make te processor reading the same word of data over and over again and therby stepping through the whole address space. http://www.baigar.de/TornadoComputerUnit/Switches.jpg With this I characterized the core memory timing, I tried to identify important lines, refined my schematics and connected a logic analyzer to all vital signals. In applying different patterns I already discovered read instructions, 2-cycle instructions, read-modify-write instructions and some instructions freezing the unit and requiring a power cycle (not only a reset pulse!): http://www.baigar.de/TornadoComputerUnit/Switches.jpg http://www.baigar.de/TornadoComputerUnit/DeviceUnderTest.jpg In parallel I did detective work on the stickers and posted my information to a thread in rec.aviation.military. This lead to the suspicion that the unit is from an early tornado aircraft (probably only from one of the first prototypes) and was responsible for controling some kind of display: http://www.baigar.de/TornadoComputerUnit/Sticker1.jpg These experiments showed me that (a) the machine is not completely dead and that (b) the command set is not compatible (this was my hope first) with the well known PDP8 or any other known 12-bit machine. So what was needed was PHASE 3 (Sep 2005) an in-circuit analyter and the possibility to read and write core memory. With quite a amount of reverse- engineering, thinking and try-and-error I discovered a DMA mechanism which in my opinion was used to load software onto the unit via the big plug - but was unused during normal operation (big plug sealed off). Since I hate any PC-stuff and I needed a powerful and real-time capable tool to generate the appropriate timing for writing into the core, I decided to use a vintage transputer board from a ParsyTec-Megaframe, running the operating system helios (beautiful unix-type parallel OS) which I connected to the Programmer Electronic Control using a homemade interface PCB and flat ribbon cables: http://www.baigar.de/TornadoComputerUnit/TrapuInterface.jpg During this process I refined my schematics again, analyzed the ALU and the timing generation and made more professional connections to the logic analyzer: http://www.baigar.de/TornadoComputerUnit/Connection.jpg Here much efford went into establishing all the tools needed - but it was worth the efford, since in this environment the complete cycle of - doing a modification (solder iron), - booting the helios (UNIX!), - triggering the logic analyzer - launching the test software - read out the results only takes 20 seconds. To be on-topic here: Vintage techniques involved in the setup: + Sun Sparc 20 for GPIB-interfacing to logic analzyer, and for booting the helios client via BBK-S4 board. + One T805 entry-node of a Parsytec PowerXplorer for development and ompiling of the helios software. This is booted from the SunSparc 20 as well. + SGI Indigo2 as frontend and data processing. Soon the timing matched what the processor does on its own. PHASE4 (Nov 2005): I inserted the core memory and tested my tools on word 0 only (read, write) and it was perfect. So the hope was to recover information still sitting in the memory. But after doing tests on word 0 and than reading the remaining 4095 words, I only discovered some type of test pattern beeing inside the memory. But now the tools worked very well allowing cycles of (1) Write test patterns (2) Let unit execute some cycles (3) Observe dataflow (logic analyzer) and read out core memory. (4) Put data into files for later analysis (dinotrace). One of these cycles takes around 15 seconds. PHASE5 (Jan 2006): Doing lots of cycles I discovered lots of commands and instructions. So this lead to defining a own assembler language. In parallel I implemented an assembler understanding the already discovered commands and generating files suitable for writing into the core memory. So it became more and more comfortable to write test programs to analyze new instructions. In this manner I analyzed systematically the whole 12 bit space to discover jump instructions, arithmetic instructions and so on. In summary this is a VERY ARCHAIC and unusual machine: - THE MACHINE HAS 1 ACCUMULATOR - THERE EXISTS ONE INDEX REGISTER (indirect addressing) - CALCULATION IS DONE IN 1-complement!!! - NO CARRY-FLAG (essentially all arithmetic only uses bit 0-11, bit 12 is sign/carry) - SHIFT-COMMANDS use a hidden 12bit SHIFT REGISTER! - There is a MULTIPLY-INSTRUCTION (did not expect this!)!!! - Only one instruction for ABSOLUTE JUMPS using a very delicate table jump algorithm. This can be used to simulate someting like a CALL (no stack on this unit!) - Really ugly! Doing this it became obvious that the unit has problems in accessing the upper 4k words of memory. In doing so it freezes, requiring a power cycle to recover. So far I was not able to locate the problem and unfortunately all attempts to get hands on a second unit for swapping the micro code and sequence generator failed. # ## ### # # # ##### # # # ### # # ## It must be a problem with micro-code since the unit can execute code in the upper half, but data access fails. In writing bigger programs I encountered problems in my transputer setup related to refresh cycles on the transputer PCB: PHASE 6 (Nov 2006): The box itself runs at 1.2us cycle time for core accesses, but the core timing has to be accurate to <30ns for proper operation. The built-in refresh of the DRAM on the transputer lead to an error-rate of approx 1% in my tools writing and reading core. So a small PCB had to be added to the transputer setup to detect this refresh cycles and to synchronize the helios software to them: http://www.baigar.de/TornadoComputerUnit/RefreshDetect.jpg http://www.baigar.de/TornadoComputerUnit/T805refreshOK.jpg With this the error rate dropped to 0.004% which is more than enough for the application. From there on the complete setup did not change any more: http://www.baigar.de/TornadoComputerUnit/SetUpPanorama.jpg http://www.baigar.de/TornadoComputerUnit/SetUpPanoramaExplained.jpg Today the assembler understands approximately 25 instructions, generates appropriate warnings and errors and warns if an instruction will freeze the unit (TCL together with m4 makes it very easy to write such a macro-assembler and tcl past 8.4.7 is reasonable fast to lead to very short compile times even on my slow hardware)... PHASE 7 (Jan 2007): A closer look at the serial links revealed that they are some type of serial, differential SPI buses, allowing messages of 12 bit + 2bit identifier + some kind of address. Not all identifiers can be sent out on all plugs. These interfaces (as my limited understanding of this is) should be panavia-link or short panlink interfaces. But sorry - I do not know any details about this: http://www.baigar.de/TornadoComputerUnit/PanLink1.gif The latest action was, to build a small interface PCB to decode the messages, i.e. seperate data from address and identifier and generate CS and CE signals. With this it is possible to connect different devices to these serial links in the future. The first device I connected two weeks ago was a small LCD display and look - it works: http://www.baigar.de/TornadoComputerUnit/ConsoleLCDonDPL03.jpg In my assembler, this "Hello World" looks like this (including initialization of the display): reset: MTA 0b00111000 ; Display Initialisieren (8bit, 5*8 chars) WDPL3.ID0 0 ; Befehl ans Display (RS=0) DELAY(4200) ; Warten 4.2ms bis Display initialisiert MTA 0b00000001 ; Display Loeschen WDPL3.ID0 0 ; Befehl ans Display (RS=0) DELAY(1640) ; 1.64ms Wait bis sich Display geloescht hat MTA 0b00001111 ; Cursor an, Display ist jetzt leer mit Cursor WDPL3.ID0 0 ; Befehl ans Display (RS=0) DELAY(110) ; 110us Wait, dann hat sich das Display konfiguriert MTA 0b00000110 ; Auto-Increment-Mode, d.h.Cursor wandert WDPL3.ID0 0 ; Befehl ans Display (RS=0) DELAY(50) ; Nach 50us Wait ist der Cursor an und alles bereit ; ; Text ans Display ausgeben ; MTA Text ; Zeiger auf Text STA Index ; initialisieren loop: LDI Index ; Naechsten Buchstaben holen LDA 0 ; und Daten ans Display (RS=1) RJAZ Fin ; falls nicht 0 (das waere Ende) WDPL3.ID0 1 ; schicken. Danach INC Index ; Index erhoehen und warten... DELAY(50) ; 50us Wait rjmp loop ; Naechsten Buchstaben Fin: rjmp Fin ; Endlos-Schleife! In this DELAY is a macro defined within the assembler and consisting of a simple loop. So this is the current state! F U T U R E : The following things are still on my to-do-list: (1) The unit has got a 12bit-start/compare timer which I currently do not have access to. (2) Approx 40 of the possible bit-patterns are not valid commands now - either I do not understand their meaning yet or the microcode is somehow defective. (3) I can read data from the plugs, but I did not discover a sync mechanism: When has data completely arrived??? (4) There is still the problem of the unit freezing in accessing the upper memory half. (5) On each serial link, there seems to be an interrupt signal. I do not know how to enable the interrupts and what action they cause (I suppose they cause a jump to a certain address in memory). So thank you for reading all this junk of bad English and maybe something was interesting for you. For me the work on this unit was a hobby and real fun. I spent around one day a month on this unit and my big hope would be to G E T H A N D S O N A S E C O N D O F T H E S E "Programmer Electronic Controls" Best regards, happy computing, Erik.

19 years, 3 months

Value of a PDP/8?

by aek＠bitsavers.org

> - Available software: Partly because of the availiability of the > hardware, there's a lot of software out there. So when you > get one up and running, you generally can do more than look > at the blinkin' lights (though that's worthwhile in itself--much > more soothing that a lot of other things). DEC computers have literally two orders of magnitude more software titles that still exist than most other systems. The closest runners up are HP and Data General, though CHM has almost no DG software. It is really sad how little software from other vendors has survived, and beleive me, I've been beating the bushes trying to find it!

19 years, 3 months

Value of a PDP/8?

by aek＠bitsavers.org

> I'm not quite sure how to get the message out there that this stuff's of > potential interest - particularly without being drowned in copies of mundane > PC software. Guess we need to just keep putting the word out that there are places around the world capable of reading old media. I'm saddened by the number of people that I contact that don't want to bother sending old tapes because they are 'impossible' to read. > I've largely come to the conclusion that it's impossible to > actively seek out - but that it does exist out there and will sometimes turn > up completely at random. Frustrating, but true. The collections I know of that are still 'latent' will probably stay that way forever, because the people who have them want to restore their machines to read the media (a REALLY bad idea..)

19 years, 3 months

VMS for MicroVAX II/III (was Re: Value of a PDP/8?)

by ajp166＠bellatlantic.net

> >Subject: VMS for MicroVAX II/III (was Re: Value of a PDP/8?) > From: "Zane H. Healy" <healyzh at aracnet.com> > Date: Fri, 09 Mar 2007 15:19:27 -0800 (PST) > To: cctalk at classiccmp.org > >> > If you want to run VMS it's fairly available. >> >> What would be the most appropriate version to run on a MicroVAX II or >> III? Are there installation tape media images available somewhere? > >Realistically? Any version you can get on a pair of good TK50's (as I >recall even V5.5 is 2 TK50 tapes). I've run V5.5 on my MicroVAX II before >turning it into a PDP-11/73. I've got V7.2 on my MicroVAX III. However, I >was able to copy the 7.2 install CD over DECnet and write it out to an RA72 >and install from that, in order to setup my MVIII. V5.5 runs well on MV-II with full load of ram. If your less than full ram consider 4.7 though 5.2 also runs ok that way. >>It's not the suggestion you want, but you should think about getting a >VAXstation 3100 or 4000 series machine. With those and a SCSI CD-ROM that >is capable of doing 512-byte blocks you can easily install OpenVMS, and then >remotely boot the MicroVAX II/III as a cluster node. > >At least I assume you aren't lucky enough to have a Q-Bus SCSI adapter. Another option is after netbooting BACKUP you can do an image copy the disk to the MVII, either net is slow but still faster than TK50!!! I've done this. The 3100 I use has a small (100mb RZ2x) and it's a bootable system though cramped and I can use backup and image copy it to RD54 sized drives via 'net. That way I clone the OS to machines then tweek it (system name and all that stuff). Saves a bunch of time and messing with TK50s that tend to do annoying things. IF you have a SCSI adaptor (even if you can't leave it in the system) you can create a disk on a 3100 or whatever and then transport the adaptor and media to the MVII and copy to the MSCP drive. Allison

19 years, 3 months

tools / test gear / components in the US?

by julesrichardsonuk＠yahoo.co.uk

Out of interest, whereabout in the US is good (mail order) for getting hold of tools / test gear and components? There's only a Rat Shack in town here, which as everyone knows is utterly useless for absolutely anything :(

19 years, 3 months

Why DEC Equipment?, was Re: Value of a PDP/8?

by marvin＠rain.org

> I feel the need to ask - what is it that makes DEC stuff so popular > and collectible, versus other machines of the same time period? > Generally they're equally as interesting, and often more so (IMHO) > due to all the quirks and design differences versus the more > mainstream DEC stuff. For me, DEC was the first "real" computer that I could actually work on. Attending the Maynard training facility was a blast. The instructors used to have us practice troubleshooting the 11/45 by putting tape on a finger "somewhere", and then we had to find the fault. I still remember a friend and I going in one night to practice, putting a piece of tape on a random finger, and taking some two or three hours to find the "problem" :). Normally, the instructor faults would take us maybe 30 minutes max. Later, I programmed an 11/05 as necessary when looking for faults in the control system for a large bakery. T'was just plain fun!!!!!

19 years, 3 months

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