- test-drb@ccmp.vtda.org - classiccmp.org

seeking DEC digital mps - microprocessor series monitor/control panel

by nigel.d.williams＠gmail.com

http://www.dvq.com/oldcomp/photos2/1k/dec_micro_panel.JPG I find this device quite fascinating (Intel 8008 plugged into a PDP-8 host), if anyone has one surplus I would be interested in negotiating. thanks. www.retroComputingTasmania.com

15 years, 8 months

7
11
0 0

Nuclear Data ND 6600

by legalize＠xmission.com

In article , Richard <legalize at xmission.com> writes: > > In article <E1P7wPP-0001ul-8h at shell.xmission.com>, > Richard <legalize at xmission.com> writes: > > > The Nuclear Data ND 6600 was some sort of laboratory PDP-11 setup. I > > have a terminal from such a system (very nice green keyboard). I'll > > upload some pics this week. > > However, I opened the case and was very surprised with what I found > inside the terminal. > > Its basically an empty box! Pics uploaded now: <http://picasaweb.google.com/legalize.slc/NuclearDataND6600> -- "The Direct3D Graphics Pipeline" -- DirectX 9 draft available for download <http://legalizeadulthood.wordpress.com/the-direct3d-graphics-pipeline/> Legalize Adulthood! <http://legalizeadulthood.wordpress.com>

15 years, 8 months

2
2
0 0

need teco suggestions

by legalize＠xmission.com

I need a TECO command suggestion that will fit in 3 lines of 18 chars each. It would be nice if I could have 5 chars leftover to have "TECO:" or "TECO " in there :-) -- "The Direct3D Graphics Pipeline" -- DirectX 9 draft available for download <http://legalizeadulthood.wordpress.com/the-direct3d-graphics-pipeline/> Legalize Adulthood! <http://legalizeadulthood.wordpress.com>

15 years, 8 months

4
6
0 0

FS on ebay: IMSAI 8080 Microcomputer and CompuPro S-100 Boards

by nick.allen＠comcast.net

For anyone interested... Just listed a fully functioning IMSAI and several compupro boards (Z80 8mhz CPU, floppy, hard drive and serial port controllers): http://shop.ebay.com/sdinet/m.html?_nkw=&_armrs=1&_from=&_ipg=50&_sop=1

15 years, 8 months

2
1
0 0

AT&T 610 terminal

by mark.kahrs＠gmail.com

My 610 burned up a few months back and I have no interest in reviving it. Is it a collectible? Or should I dispose of it at the local Goodwill?

15 years, 8 months

4
4
0 0

RL01/RL02 cables and terminators and unit plugs (was Re: PDP-11/34A bring up)

by ethan.dicks＠gmail.com

On 11/9/10, Tony Duell <ard at p850ug1.demon.co.uk> wrote: > The cables are differnet betwene the RLs and the RK06/07 (the latter has > all pins bet one (termintor power) connected That rings a bell (term power). > the former has rather fewer > wired), but AFAIK the terminator is the same (it terminates all signal > pins. I think at least one RL controller printset shows the exploded view > of the terminators with 'First used on Option/Model : RK06' specified. OK. That's a good detail to remember when setting up drives of either kind. One handy bit of trivia if you happen to have spare Unit plugs from the high numbers of an RK06/RK07 set is that they work in an RL01/RL02 if you mentally mask off 2^2 (i.e., an RK06/RK06 plug labelled "4" is "0" on an RL01/RL02). It's the same sort of switch/bulb housing, but one less bit going back to the electronics. We didn't do it often, but sometimes we were short some of the numbers and we did have a couple of RK07s and a drawer of random unit plugs. -ethan

15 years, 8 months

2
1
0 0

Gandalf

by tshoppa＠wmata.com

De writes: >> I am looking for info on a Gandalf LDS120 modem, specifically the >> serial port pinout. > In the division of irrelevant to the original question, I thought these > things were line drivers, not modems. I always thought they got lumped into "short haul 4-wire modems". They do have "DCD" lights on the front. I seem to recall that it's just a light and doesn't actually assert any RS-232 pins. But they could just be differential line drivers probably with isolation. 20+ years ago I'm sure I looked inside to see what's in there but I can't recall. I always thought they did some simplistic and almost certainly not Bell-standard FSK or PSK but that was just my impression, no actual evidence to back that up. Did the 4-wire screws on the back have labels of "+" and "-"? That would be a point in favor of them being line drivers and not modems (although some simple modems were in fact phase-sensitive). We used them between serial concentrators on different floors or between serial concentrators between nearby buildings. I note that there's no Gandalf directory at bitsavers. Gandalf certainly has a unique heritage not really being a "computer" company in the usual sense but for so many of us it was the gateway from terminal to the computer or between computers. I get the impression they were far more common at large academic institutions than at any commercial site. Tim.

15 years, 8 months

3
3
0 0

Old terms...

by bqt＠softjar.se

On 11/09/10 10:44, Roger Holmes<roger.holmes at microspot.co.uk> wrote: >> > From: Johnny Billquist<bqt at softjar.se> >> > >> > Gah. I have no idea what PPU mean, nor PP. > You're probably just not old enough. That is definitely true here. :-) > In the 50s the main processor was called the CPU (Central Processing Unit) to differentiate it from the various PPUs, (Peripheral Processing Units). The first machine I programmed, the IBM 7094 had a CPU and two PPUs, one to read cards and write the images to tape transports, which would then be switched over to the CPU to read, compile and execute the job and write the results back to another tape transport which then got switched to the other PPU which then transferred the tape image to a line printer. Thanks. That explains it. > Somehow now (when most peripherals have embedded processors which could be called PPUs) we seem to have stopped using the term. Yeah. It might have gotten lost in the inbetween years when computers were trying to get rid of, at the time, expensive peripherials (they were expensive enough without being their own computer). I only started playing with computers in those inbetween years. :-) Johnny

15 years, 8 months

1
0
0 0

S-100 board PCB planning

by lynchaj＠yahoo.com

Hi! Over the last couple of years several of us at N8VEM, S100computers.com, and others have been building S-100 boards. This summer we did a major update/respin cycle to the boards and made manufactured PCBs for many builders. For a while it seemed to satisfy the demand for DIY hobbyist S-100 PCBs but now the interest is starting to pick up again so I thought I would send an update to any S-100 enthusiasts on CCTALK. I will reorder/respin S-100 PCBs once the interest level gets to an economically viable level for a group purchase. Normally that is around 25-30 PCBs I know builders want which makes a cost at $20 plus shipping per PCB affordable for most builders. This compromise balance seems to work well and we've produced several S-100 boards this way. Here are the boards we've made so far: S-100 regular prototyping board (some remaining) S-100 buffered prototyping board (some remaining) S-100 backplane (8 slot plus utility circuitry - one left) S-100 IDE (hard drive, CD-ROM, CF, ATAPI, etc) S-100 parallel ASCII keyboard (just received a new batch of respin PCBs) S-100 4MB SRAM (Flash, etc) S-100 system monitor (similar to Jade Bus Probe but two PCB set - one or two remain) S-100 bus extender (with logic probe, indicator LEDs, etc) S-100 EPROM (SRAM, EEPROM, Flash, etc) S-100 IO (dual serial, USB, voice synthesis, etc) S-100 PIC/RTC All of these have gone through at least one or two internal prototype iterations plus one or more manufactured PCB orders. Since we respin the boards based on builder feedback obviously the later generations of boards tend to be "cleaner" than the earlier ones. This is an all volunteer amateur project so the builders *are* the developers, QA, testers, etc in addition to using the boards. There are four boards in active development and/or approaching manufactured PCB stage S-100 Z80 CPU (just ordered first batch of manufactured PCBs after two rounds of prototype build and test) S-100 Console IO (dual Propeller VGA, PS/2 keyboard, microSD, Ethernet, etc - first iteration prototype boards ordered) S-100 ZFDC intelligent floppy drive controller (Z80/WD2793 second iteration prototype board imminent) S-100 68K CPU (first iteration prototype boards ordered) Please note the above boards no longer *planned* they are actual boards in some form or another. There are several more in the planning stages but I won't waste your time with those since those plans change often. All of the schematics, PCB layouts, bill of materials, etc are available on either the N8VEM wiki or S100Computers.com website including build instructions for the most part. These are noncommercial Do It Yourself (DIY) hobbyist PCBs. They are not perfect nor is this a business. John's apt description from comp.os.cpm captures it well "Andrew Lynch (at N8VEM) see (http://n8vem-sbc.pbworks.com/) and I, are in the process of having a few commercial quality S-100 cards made for ourselves. If others are interested in obtaining a bare card, let Andrew or I know. Please note these would be bare cards, a schematic and that's it. Building the board and implementing CPM etc., you are on your own. This is not a project for first timers." In other words, if you want to play along that's great but this is purely "CAVEAT EMPTOR" and there are no assurances, guarantees, or warrantees on any aspect of the boards. Please this is offered as an information post to interested vintage/classic computer hobbyists not an invitation for flames and pointless criticisms. Please be courteous and keep those to yourself. As always, questions, comments and *constructive* criticism welcome. Thanks and have a nice day! Andrew Lynch

15 years, 8 months

5
6
0 0

Advin PILOT-142 programmer sw?

by chrise＠pobox.com

I was recently given an Advin Systems PILOT-142 device programmer... but of course no software with it. I downloaded Advin's Captain v1.34 software for XP from their website, where they claim support for the model -142 but after installing and launching the software, it reports that it does not work with the "revision" of my programmer. There are no revision or series marks on the unit other than the PILOT-142 sticker above the power switch... so I don't know what makes it different. Email to Advin says they have NO software that supports the -142 even if their website says otherwise. In any case, I'm looking for anyone that might have DOS or Win software for this older beast. It would be a nice unit for burning 2716, 2732 and a number of old PALs that I would like to do. Chris -- Chris Elmquist

15 years, 8 months

3
4
0 0

Ten P112 kits-a-cookin

by dgriffi＠cs.csubak.edu

The leftover P112 parts have arrived in Portland. We're now working out what more needs to be bought to make kits. There will be ten kits. This means that if all the preorderers take one, the last one who put down for a preorder will not get a kit. I think I've already refunded your money anyhow. If one of the ten declines to take a kit, the will be offered to you (you know who you are). I'll keep the list informed on further developments. -- 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?

15 years, 8 months

1
0
0 0

PDP-11/34A bring up

by chrise＠pobox.com

I am the new keeper of the PDP-11/34A that Jack Rubin rescued a while ago and wrote about here, http://decpicted.blogspot.com/2010/01/pdp-1134a-data-systems-design-dsd-880… I took it on a road trip from Chicago back to St. Paul after VCFMW in September. I've been doing a lot of cleanup on it and finally got to the point where I could power it on (just the CPU box) this weekend. I think now I need to learn about Grant Continuity ;-) There is a M9302 terminator installed in the last slot (left most when looking from the front of the machine) and also an M9312 in slot 4 (amoungst the CPU and cache cards). Two of the original boards are removed from the backplane... the DSD 808830 controller and the DILOG DU130 tape controller. They were in slots 12 and 13. I then also have an RL11 on hand but it is not currently installed in the machine. When I power up the machine, it immediately lights the RUN light on the KY11-B programmer's console. No matter what I do from that console, I cannot get it to exit RUN or print anything to the serial terminal. However, if I remove the M9302 terminator (a trick I found on some web page), then sure enough, I can HALT it, the RUN light goes out and I can do CTRL+BOOT and the serial terminal will spring to life with a register dump and the '@' prompt. I'm pretty sure that my problem is the empty slots 12 and 13 where boards used to be and should now have Grant Continuity cards installed instead... but I am curious why pulling the M9302 makes it "work". What is the mechanism at play there? I also suspect that I may have to look at the backplane wiring for slots 12 and 13 to put back whatever DMA jumpering might have been modified for the two cards that used to be there-- or, at least for one of them as I can probably put the RL11 into one of those slots and it requires DMA. Chris -- Chris Elmquist

15 years, 8 months

7
10
0 0

Dell Refurbished DEC (?!)

by robert.jarratt＠ntlworld.com

Just noticed a number of items like this one http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=260689944041 appear on eBay. These are strange listings. First I would be very surprised if Dell refurbished vintage DEC stuff. Second it is listed as refurbished but is also described as being in New condition. Has anyone ever dealt with this seller? They seem to have good feedback. I wouldn't buy at that price in any case, but just curious I suppose. Regards Rob

15 years, 8 months

2
1
0 0

Help with testing Sun CP1500-440

by auringer＠tds.net

Hi all, I recently acquired a SPARCengine 440, which is a CompactPCI form factor SBC. I don't currently have a cPCI chassis in which to test this thing. Normally I would just hang onto this and wait for a chassis to present itself, but I would like to know if the card works before spending resources on the chassis. Is there someone that would be able to help me out with some testing? I think I could make it worth your while. Thanks, -Jon

15 years, 8 months

4
15
0 0

Amstrad 3in disc drive troubleshooting

by classiccmp＠philpem.me.uk

OK, this is seriously weird. I have two Amstrad 3-inch disc drives: an EME-156, and an EME-231. Both drives will spin up, select and generally "work". For varying values of "work". On both, the "activity" (selected, whatever) LED is stuck on at half-brightness, but switches to full brightness when the drive is selected. For reference: both drives are showing the exact same symptoms. I can select the drive, spin the motor, and seek around the disc. Writing seems to work (more or less) -- when WR GATE goes low, the coils of the head are driven to ~10V with smaller positive and negative pulses (sort of like an exponential curve, synchronised with the falling edge of WRDATA). When WR GATE goes high again, the head voltage falls back to about 2V. When I try and read anything, the head shows no response whatsoever. No pulses on either side of the head at any amplitude (measured with a 1:10 probe on a Tek TDS2024B). Similarly, RD DATA shows no pulses either, except for a brief glitch (2.8us or so) when the drive is selected. The drive controller ASIC also gets rather hot.. like, too hot to touch. I've confirmed that the power is correct -- 12V and 5V have been applied to the correct pins. I'm using "new old stock" Amsoft discs which I bought from an ebay seller. No idea if they're good or bad, but they arrived in shrink-wrapped side-opening plastic boxes and were apparently "Made in Japan." My current suspects are: - Discs. The discs aren't actually magnetically coated in any way, or the coating has failed in some way. Catch is, I don't have a known-good disc to test with. - Heads. Dirty, out of alignment or otherwise completely pooched. Can anyone suggest some things I could check, or are these drives likely to be toast? Thanks, -- Phil. classiccmp at philpem.me.uk http://www.philpem.me.uk/

15 years, 8 months

6
22
0 0

Crucifixion (was Re: Fragility in the floppy world (was Re: TRS-80 Model II Manuals))

by roger.holmes＠microspot.co.uk

On 7 Nov 2010, at 18:00, cctalk-request at classiccmp.org wrote: > > Message: 7 > Date: Sat, 6 Nov 2010 21:15:55 +0000 (GMT) > From: ard at p850ug1.demon.co.uk (Tony Duell) > Subject: Re: Fragility in the floppy world (was Re: TRS-80 Model II > Manuals) > To: cctalk at classiccmp.org > Message-ID: <m1PEq7C-000J48C at p850ug1> > Content-Type: text/plain > >>>> Oh, go ahead... But I beleive that cucifixion has never been used as a >>>>> suicide method. >>>> No. I've tried it dozens of times; there's just no way you can hammer in >>>> the last nail. >> On Fri, 5 Nov 2010, Tony Duell wrote: >>> I have this image of 4 of those butane-powered nailers used by builders >>> suitably arranged nad with a remote triggger facility. You get your arms >>> and legs in the right places, somehow press the switch and bang... >> >> You might be able to get away with one of the Sears "Nextec" cordless >> electric hammers. > > Except that I am in the wrong country for this. > >> >>> No I am NOT thinking of trying this. >> So, the technique remains untested. > > Do you _really_ want me to try it? Definitely not, for one thing you would not be able to report back the result of the test if successful, only if it failed. A bit like testing the I/O instruction that a torpedo's processor issues to explode its charge, and the code it executes afterwards. The Q.A. department of course would insist that the absence of a detonator and charge might affect the result of the test so must be connected up. We do get into some weird discussions don't we, like guns. What's next? Using classic computers for "sex and drugs and rock and roll"? World domination? Extermination of parasites? Building of DNA molecules to breed a super intelligent organism which will then decide to eliminate what it regards as parasites, the human race? If you must go off at tangents, please at least change the subject line! Roger Holmes

15 years, 8 months

9
10
0 0

Virtual memory

by bqt＠softjar.se

On 11/06/10 02:03, Brent Hilpert<hilpert at cs.ubc.ca> wrote: > Flogging a dead horse perhaps, as I believe the discussion is simply a > matter of differing definitions of the phrase "virtual memory", but > let's try a different approach: Nothing like flogging dead horses... :-) > Suppose we have a machine which at the instruction level provides > 32-bit addresses, that is, it presents a 32-bit address space (4GB) to > the user. However, there is only 1 MB of physical RAM memory in the > machine. That is one scenario, but definitely not the only one. Part of the problem is that people seems to want to limit them self to this scenario, and of course, if you start at that end, then you will more or less always end up in the same place you just do here. :-) > Without trying to go through the whole history of OS development > (leaving out things such as overlays, shared libs, etc.), and without > accounting for memory required by the kernel/OS for simplicity, > consider several scenarios: > > - 1. User addresses map directly to physical addresses. > User address 0 is physical address 0. The user address space is > obviously > limited to 1MB or less of memory and the user will be aware of such > if an > attempt to address beyond that is made. Yes. And if you have several processes, they are all aware of each others memory space, and care must be taken that they do not wander outside their own confinements and clobber things in the system (including the OS). Programs must be written to be memory aware, and either PIC, or else linked to run at a specific address, since there is no virtual memory. > - 2. We add an MMU to map addresses. > Multiple user address spaces may exist and can be mapped to different > areas in physical memory. User address 0 may or may not ref physical > address 0. > A user is still aware of a limited address space dictated by the 1MB > of > physical memory. The total of the user address spaces cannot exceed > 1MB. Indeed. And it can be an arbitrary lower limit than 1 MB as well. And at this point, programs can be written to not be memory aware. All programs can be written without consideration to what addresses they use. All can be linked to start at the same address, and run in parallel. They are not aware of, nor do they see other programs memory space. They can be PIC, or position dependent. They can clobber all their memory, and the system itself is not affected. > - 3. We add swapping-to-disk. > The system as a whole is no longer limited to 1MB of memory, there > may be > multiple user address spaces totalling more than 1MB of memory. Each > user > however, is still limited to a max of 1MB of address space, i.e. > each user > is still aware of the limited physical memory. Right. Adding swap does nothing more than grow the capacity of the system total. For a single process, it is invisible. > - 4. We add address-faulting, demand-paging - whatever one wants to > call it. > The user address space is no longer limited by physical memory. The > user can > hit any address in their 32-bit space and (magically) find a valid > memory > location there. More physical memory can be added (or removed) > 'underneath' > the user(s) without their awareness. Except, or course, the OS can still limit you to use less than 1 MB. Adding paging does nothing for the individual program as such. It is totally invisible. You might argue that it gives you the possibility to use more memory than physically available, and that is true, but that is at the discretion of the OS. To get more memory, you will need to call the OS to request more memory, and the OS can allow or deny this request. Same as in #2 above. > By the nomenclature I grew up with or suffer under, the term "virtual > memory" only applies in scenario 4, although "virtual addresses" could > be said to have been introduced in scenario 2. The difference between 2 and 4 is only that the OS *can* allow you to use more memory in scenario 4, not that it necessarily will allow it. > Or, scenario 4 was my understanding of the *commonly-agreed-upon > application* of the phrase "virtual memory", although I would not argue > that in a very general sense it may be applied to scenario 2 or 3. The difference between 2, 3 and 4 is actually extremely vague. The only actual difference is that the OS *can* allow you to use more memory. But let's say that the OS will not. Does that suddenly mean that you don't have virtual memory, even though it is indeed using page demand loading and all that fancy stuff? And this also totally ignores the scenario that exists under the PDP-11, and which started this thread. What if you have more physical memory than can be addressed by virtual memory? That's a whole different ballgame, and is not covered by any of your scenarios... All in good spirit. :-) Johnny

15 years, 8 months

2
1
0 0

Core memory repairs, part 2.

by jdr_use＠bluewin.ch

I spend some more time on the severely defective 8/L core stack I have. First I repeated the diode checks and wielded out all diodes that were more than 40mV away from the .55 V forward voltage that seems to be standard. Total number of defective diodes : 29 . Still cannot figure out why so many diodes were dead/shorted. Also repeated the inhibit / sense wire checks : 1 sense wire open. 1 sense wire high ohmic. ( 200 ohms ) 1 inhibit wire high ohmic ( 250 ohms ) Normal value for sense / inhibit wires would be around 15 ohms. I then opened the stack by cutting through 128 X/Y wires and removing 256 wire halves... There were several old repairs, covered with some ceramic substance, luckily all on the edges of the core mats. The high ohmic wires were due to this old repairs, after scrubbing off the ceramic stuff and resoldering the connection the high ohmic sense wire was restored to its nominal 15 ohm value. I still have to fix the other wires, ( i.e. 512 wire halves to remove...) and reassemble the stack, but it looks like core memory repairs are possible by amateurs. Material needed : - high powered, but comfortable, microscope. - SMD pencil soldering iron. The smallest I could find, and it was still too big. - the smallest solder I could find, still way too big. The other core stack, with the one single bit error, is still closed, but by swapping sense wire I was able to confirm that the error is indeed in the stack. Jos Dreesen

15 years, 8 months

2
1
0 0

CPU scrap

by teoz＠neo.rr.com

While browsing on ebay lately I noticed CPU scrap going for quite a bit of money, for example: http://cgi.ebay.com/1-lb-Lot-high-yield-CPU-gold-scrap-recovery-486-/220690… Seems like 486 era chips (ceramic) are getting melted down for gold, and those poor PPros are going to be rare as dodo birds in a decade. Kind of makes me wonder if anything is going to be around from the 90's computer era in a dozen years. How much of the earlier stuff was saved from melting because gold was only worth $350 an ounce in the booming 90's compared to $1390 in the current depression? TZ

15 years, 8 months

13
29
0 0

Terak Boot behavior?

by derschjo＠mail.msu.edu

Hi all -- I've made a small bit of progress with my new Terak. The power supply seems to be working fine, and after going over everything and cleaning the old crumbly foam out, cleaning edge connectors, and reseating everything it now gives the impression that it's trying to boot. (And Al's been kind enough to send me a few images from the CHM, so I have something to try and boot!) However, I've never actually seen one of these in action before, so I have no idea what the expected behavior actually is. I currently get nothing on the display (the CRT is lighting up and if I turn the brightness up I can see a raster, so I know it's at least minimally functional) and I get no sounds from the speaker. The drive seeks back to track 0, pauses for 1-2 seconds and then and seems to briefly access the disk for another second. Then, nothing. Can anyone who has used one of these before tell me if this is anywhere close to expected behavior? Is it possible to get a serial console on these (and is there anything like a PDP-11 ODT prompt?) Thanks, Josh

15 years, 8 months

2
1
0 0

RTEM-11 Questions

by jhfinedp3k＠compsys.to

I am attempting to enhance a program which runs under RSTS/E, RTEM-11, RT-11 and TSX-Plus. Thus far, I have managed to support these enhancements for all but RTEM-11 due to the lack of documentation on RTEM-11. When I requested help with supporting such programs under RSTS/E, John Dundas provided a reference document which cleared up many questions. Does anyone know of a document (and its link if it is on the internet, especially at bitsavers) which describes the support provided by RTEM-11 for programs which also run under RT-11? From the comments that I have seen, the RT-11 operating system is run under RTEM-11 with special "hooks" to interface to RTEM-11. If my understanding is correct, then all of the RT-11 EMT requests supported by an RT11SJ monitor will also be available when running under RTEM-11. There are also two other specific questions that I suspect have a simple answer: (a) How much memory does a user program have which runs under RTEM-11? My assumption is that a user program has approximately the same size of memory available when running under RTEM-11 as it would when running under the RT11SJ monitor on a PDP-11 with 64 KBytes of physical memory which usually (when no additional device drivers are present) ends up being approximately 48 KBytes or an address range from 0 to about 120000 octal. (b) Whereas RT-11 actively supports the ability of device drivers to be LOADed and UNLOADed at any time based on which devices are in active use, RSTS/E and TSX-Plus require the device drivers of any device that is active to be LOADed at all times. It would be an assumption on my part, but I tend to assume that under RTEM-11, any available devices are already LOADed by the actual operating system that controls the CPU. Specifically, if a user program performs the .DStatus RT-11 EMT request for an available device, the 3rd word of the device driver information will always be non-zero which specifies that the device driver in question is always in memory and that a .Fetch RT-11 EMT request would be redundant. Can anyone provide any documentation sources? If anyone knows the answer to the approximate size of memory available to a user program running under RTEM-11 and / or the answer concerning the LOADed status of a device driver, it would be greatly appreciated. Jerome Fine

15 years, 8 months

1
0
0 0

PDP-11 firsts?

by bqt＠softjar.se

On 11/06/10 02:03, ard at p850ug1.demon.co.uk (Tony Duell) wrote: > >>>>>> > >>> > > The Philips P800 series has the PC as a general register (register 0). >>>>> > >> > >>>>> > >> > Could you use it like any other register? >>> > > There were some restrictions. I don't think you could shift it (at least >>> > > ont on the P850). But for many instructions it was just another register. >> > >> > Cool. So you could add to it, index by it, and so on? > I think so. I can't find my programemrs pocekt guide fo the machine at > the momnet. But I am pretty sure that register 0 could often be used like > any other register. Ok. Nice. > There is at least one oddity. There are no autoicrement/autodecrement > adressing modes on the P800s. However, in some cases, if you use the PC > in some instructions it is autoincrements. For example the 'immediate' > addrtessign mode isessentialy a (PC) operation (i.e. take the word > pointed to by register 0) and has that bit pattern. But for obvious > reaosns the PC is autoincrements then. The PDP-11 actually pulls that trick on a few addressing modes as well. Addressing mode 6 and 7 autoincrement the register if it is the PC, but not for other registers. (So a thing like MOV FOO,R0 is encoded as MOV x(PC),R0 .WORD .-FOO and the PC should obviously be incremented again here, but x(Rn) does not exist as a variant with autoincrement of the register.) >>> > > I guess the P800 wasn't totally ortogonal but it was a lot more >>> > > orthogonal than many other machines. >> > >> > Indeed sounds nice. When did the machine appear? > My P850 CPU service manual is copyright 1972, which alas puts it after > the PDP11, but I thoguht the series was around a bit before that. Hmm. Maybe still a first for the PDP-11 then...? :-) >>>>>> > >>> > > What do you mean by condition codes here? >>>>> > >> > >>>>> > >> > The four low bits of PSW. >>> > > Err... I don;t think that's helpful. Quite a lot of machines with a >>> > > status register have a 'low 4 bits' of it:-). But that doens't make them >>> > > condition codes. Similarly uf you hapopen to implement the same >>> > > functionality using other bits of a status registers, doesn't that make >>> > > them condition codes? >>> > > >>> > > What I was asking was what fucntionality do you require of these >>> > > condtiion codes other than there being conditional jumps on carry, zero, etc? >> > >> > Sorry. I was just being lazy, and trying to explain condition codes by >> > referring to what they are on the PDP-11. >> > >> > To try and be more specific then: condition codes are bits that are >> > set/reset as a result of operations performed by the processed, and upon >> > which you can the make conditional branches/jumps on. > Now the P800 has a very odd way of doing this. There is a 2 bit status > registers. It is set differnet ways according to the results of some > instructiuos (for example, an arithmetic instruciton will set it one way > if the result is 0, a differnet way if there's a carry out, etc). I/O > operations set it one way for device ready, another for certain errors, etc. > > The condtional branches have a 3-bit condition field. You can branch on > the status beits being any particualr value (00, 01, 10, 11), them not > being one of 3 values 9I forget which one is omitted) or 'always' Sounds slightly different than the condition codes of the PDP-11 then, but not really like the immediate test and do instructions like the PDP-10. Closer to the PDP-11, it would seem. Johnny

15 years, 8 months

1
0
0 0

Virtual memory

by bqt＠softjar.se

On 11/06/10 02:03, "Chuck Guzis"<cclist at sydex.com> wrote: > On 5 Nov 2010 at 15:09, Brent Hilpert wrote: > >> > By the nomenclature I grew up with or suffer under, the term "virtual >> > memory" only applies in scenario 4, although "virtual addresses" could >> > be said to have been introduced in scenario 2. > My original definition was that "virtual memory" was the ability of a > system (hardware, software, whatever) to fool a program into thinking > that there was more memory present than was physically the case. > > Johnny (and please forgive me if I got this wrong) tied it into the > ability to present each user with a address space, such that two > users could use the same address space, but have different data. Key > was the claim that a system with more physical memory than the user > could directly address still qualified as virtual memory. > > I don't tie virtual memory into paging or even to multi-tasking or > multi-user, although I'll concede that paging is a way (albeit > rather simple-minded) to implement it. The Burroughs B5000 didn't > employ paging and yet I think few would argue that it did not > implement virtual memory (and quite possibly the earliest commercial > use of it). Yeah, you got more more or less right. Virtual memory according to me (well, I got the definition from DEC) is the appearance of memory that is your "own" although you in fact are running on a system with many processes running concurrently. You can do anything with your memory, and it will not affect anyone else. It's like your own sandbox. You can do anything in there. Obviously, this is not really tied into paging, nor multi-tasking (you can have this with just one process, still protecting the OS from you). Obviously, I do not tie memory sizes on either end to what virtual memory is. You know, things like overlays are actually a form of paging as well, and is a solution to allow you to have more memory used than physically exist in the computer, and yet it don't require virtual memory to implement this. (Heck, I just came up with an example of paging and memory sizes that is totally disconnected to virtual memory, or page tables, or anything close to that.) Johnny

15 years, 8 months

1
0
0 0

S-100 board PCB planning

by lynchaj＠yahoo.com

http://classiccmp.org/pipermail/cctalk/2010-November/293791.html >Hi Andrew. > I am restoring a Northstar Horizion. Would any of your boards be suitable >substitutes for the original NS ones? > > >Regards >? >Rod Smallwood Hi Rod! Thanks! The boards would likely work in a NorthStar Horizon as it is a fairly normal S-100 system. The boards are designed to be strictly IEEE-696 compatible so either they would work as is or require some minor adjustment. They are not strict NorthStar replacement parts though. They would compliment a NorthStar system nicely I think but it would depend on the board and how you use it. It is hard to say without knowing your specific application though. Allison covered the topic pretty well in her commentary. My recommendation is to check out S100computers.com and see the documentation on the boards and see if this would interest you. There are a lot of photos, explanations, and videos of the various boards in action. http://classiccmp.org/pipermail/cctalk/2010-November/293798.html [Alexandre Souza] > Andrew, I'm **VERY** interesting in knowing more about S-100 boards. How >much would it cost? > The S100computers.com and N8VEM S-100 boards are an all volunteer amateur run project. They are roughly at cost for the PCB manufacturing. They are $20 per PCB with $3 shipping in the US and $6 shipping elsewhere. These are group purchases of boards for hobbyists by other hobbyists. I am not soliciting sales for the boards. What I am asking is if hobbyists are interested in getting these boards to contact me and tell which ones they want. I will order/reorder boards when the "waiting list" for any given board gets large enough to warrant an order. This is not a business as I am trying to organize a group buy of the boards. John and I are ordering boards for ourselves anyway so I thought to offer to the community if there were other interested hobbyists. There are about 50-60 S-100 builders on the private distribution list now. All of the boards are documented at S100computers.com and the N8VEM wiki. The design information for hardware, software, schematics, PCB layout, parts list, build instructions, etc are freely available and posted online. If you can't find it please ask and hopefully I'll update the website. I hope this helps. Thanks and have a nice day! Andrew Lynch

15 years, 8 months

2
1
0 0

FFS Sun monitor

by rdawson16＠hotmail.com

From: rdawson16 at hotmail.com To: innfoclassics at gmail.com Subject: RE: FFS Sun monitor Date: Mon, 8 Nov 2010 16:50:16 -0600 Paxton's got the scopes too. Its good to see stuff go to a good home. Fellow packrats unite! Randy From: rdawson16 at hotmail.com To: innfoclassics at gmail.com Subject: RE: FFS Sun monitor Date: Mon, 8 Nov 2010 16:24:07 -0600 Hi Paxton, Its yours. Call me and we will arrange things. I need to leave here by 5PM tomorrow for a ham meeting... I also have a couple of oscilloscopes, low end, probably 5 MHz bandwidth a Sencore and a Heathkit, 5 inch CRTs if anybody wants them. Randy 503-352-4612 > Date: Mon, 8 Nov 2010 13:46:42 -0800 > Subject: Re: FFS Sun monitor > From: innfoclassics at gmail.com > To: rdawson16 at hotmail.com > > On Mon, Nov 8, 2010 at 1:54 AM, Randy Dawson <rdawson16 at hotmail.com> wrote: > > > > Its large and heavy 19" ... > > > > Works fine with vga at hi res,and has attached cables for the sun. > > > > Its going to the recycle unless you guys want it. > > > > Randy > > > > > Hi Randy, > > I am interested in the monitor. I have a couple of Sun boxes that do > not have a monitor. > > I am in Eugene at the moment but going back to Astoria tomorrow, Tuesday. > > I could stop by tomorrow afternoon on my way through if it is still available. > > Paxton > > > > -- > Paxton Hoag > Astoria, OR > USA

15 years, 8 months

1
0
0 0

Virtual memory

by bqt＠softjar.se

On 11/05/10 19:13, "Chuck Guzis"<cclist at sydex.com> wrote: > On 3 Nov 2010 at 20:47, Johnny Billquist wrote: > >> > Ok. So, a program would think it addressed a memory space, which was >> > it's own, and the addresses it used would in no way related to the >> > actual physical memory it ended up referring to. I'd call that virtual >> > memory. Although, having to map the whole virtual memory as one chunk >> > to physical memory makes it a little more work, end less flexible than >> > having pages. And it pretty much prevents you from ever being able to >> > share memory in a reasonable way between processes. > Well, not really. I refer you to the CDC 7000 SCOPE 2 operating > system. There's a users' manual on bitsavers, but I suspect the > design notebooks have long vanished from the face of the earth--so > there's no documentation on the innards. I tried to find any manuals on bitsavers, but I can't see anything about a CDC 7000 there... But while I can see that doing shared memory would be possible even with a single mapping between virtual and physical address space, it would mean you need to copy data between different locations between each context switch, which would be rather heavy. > At any rate, the CDC 7600 OS people had a peculiar problem. On the > 6000 series of machines, PPUs are free-range; they have access to all > of memory and at the time (say, 1968), comprised most of the > operating system--there was almost no CPU code involved. You'd stick > a request into your own location 1 and PP 0 would see it and detail > off the work to the rest of the PPs. Very cool--you never gave up > control of the CPU unless it was to yield to the job scheduler. Gah. I have no idea what PPU mean, nor PP. But it sounds like what you describe now would not be virtual memory. If each process have access to all of the memory, then you'd not have your own address space. Instead you'd have to make sure you kept within your bondaries. Hopefully the hardware can assist with that, but maybe not. But that is still something else. It's basically just talking about physical memory. But I might very well totally be misunderstanding things here, since (as I said) I don't know what these acronyms really mean. > But this wasn't possible on the 7600, as each PP was assigned its own > hard-wired slot in CPU memory and was unable to access anything but > that. So the 7600 PPs were detalled off to I/O only. (Now, I'd call > that memory-mapped I/O--you want to to talk to a certain I/O > processor, you communicate with it through a hardware-fixed location > in memory.) Which left the CPU to handle OS tasks such as job > scheduling and file management. A whole new can of worms, as SCM > (the memory that a program could execute from was very fast, but > somewhat limited). To me, the difference between shared memory I/O and memory mapped I/O is about how the notification comes across between the subsystems. Is the slave triggered by a write to the memory, or does the slave poll the memory location. If the slave polls the memory location, then I'd called it a shared memory design. If the slave gets triggered by a write to the memory, then I'd call it memory mapped I/O. And what you describe here could further be called I/O channels, I think, in IBM speak. Basically, separate processors running their own code, which can do limited kind of stuff, mostly related to I/O functions for the main processor. Some of these designs even allowed you to place the "program" to be run in shared memory, and then kick off the I/O processor to do the work, and it signalled back when it was done. But I digress... :-) > A small permanently-resident "kernel" to handle PP commination and > task swapping was written, but job processing, file management, etc. > was performed for each job with a sort of matryoushka doll setup of > overlapping field lengths. In other words, a user program was > completely enclosed within the record manager which was completely > enclosed within a buffer manager which was completely enclosed within > the job supervisor for that job. So all user memory was shared with > successively higher privilege level tasks, differing only at what > location their respective location 0s were assigned to physical > memory. Ah, yes. That is also shared memory between different processes, but in a somewhat limited hierarchical way. You could for all OSes say that any process is always sharing it's memory with the operating system. :-) > The 7600 also had a bulk core "LCM" which couldn't be executed from, > but served for swapping and data storage. > > As far as piecemeal swapping, I'll leave that for another time when I > discuss the CDC Zodiac operating system (1970), something for which I > suspect no documentation survives. Sounds like fun... Johnny

15 years, 8 months

2
1
0 0

Gandalf

by tshoppa＠wmata.com

> I am looking for info on a Gandalf LDS120 modem, specifically the serial port pinout. I recall it's just 2, 3, and 7, i.e. no hardware flow control, and probably not even DTR/DSR. Now whether 2 and 3 have to be swapped...well I always just tried it both ways until it worked :-) And it's 4-wire leased line on the analog side, right? So no ring detect etc. either. Tim.

15 years, 8 months

2
1
0 0

Any ideas what chip goes in this socket?

by ard＠p850ug1.demon.co.uk

The device [1] that's currently all over my bench has an empty 28 pin DIL socket on one of the PCBs. It's alongside a 27C256 EPROM and 43256 RAM, and has a similar pinout. In fact the pinout is the standard JEDEC one for 28 pin memory devices (with A13 on pin 26, WE on pin 27, OE on pin 22, etc) with one exception. Pin 1 is not A14, it appears to be an output, linked to an interrupt pin on the 80C85 that links to the aforementioned memory devices and this socket). Oh, and to an input port pin. Any ideas? My first thoughts were an E2PROM or simular, with a ready output on pin 1, or a RTC/memory device with an interrupt output on pin 1, but I can't find any obviuos candidates. [1] A telephone network simulator. OK, it's not a classic computer, but I will be using it to test and demonstrate classic computer modems, it's well over 10 years old, and contains 6 microprocessors... -tony -------------------------------------------------------------------- myhosting.com - Premium Microsoft? Windows? and Linux web and application hosting - http://link.myhosting.com/myhosting

15 years, 8 months

2
2
0 0

Gandalf

by two_bit_mem＠yahoo.ca

Hello I am looking for info on a Gandalf LDS120 modem, specifically the serial port pinout. TIA Marty

15 years, 8 months

2
1
0 0

FFS Sun monitor

by rdawson16＠hotmail.com

Its large and heavy 19" ... Works fine with vga at hi res,and has attached cables for the sun. Its going to the recycle unless you guys want it. Randy

15 years, 8 months

4
7
0 0

Weird discussions, was Crucifixion (was Re: Fragility in the floppy world (was Re: TRS-80 Model II Manuals))

by dm561＠torfree.net

Date: Mon, 8 Nov 2010 08:28:03 -0800 (PST) From: Cameron Kaiser <spectre at floodgap.com> Subject: Re: Weird discussions, was Crucifixion (was Re: Fragility in the floppy world (was Re: TRS-80 Model II Manuals)) > > I once dated a girl who was a DEC geek (she grew up > > around PDPs), and she wanted to have, erm, "physical > > relations" atop my VAX 8700. > > Now we know the "real" reason the Cray-1 was C-shaped. > > A whole new classification of computers! > > - if you can have physical relations inside it, it's > a mainframe > - if you can have physical relations on top of it, > it's a mini-computer > > - if you can get involved with someone who would > like to test those characteristics you're amazingly > lucky Dr Pepper -> keyboard +++++++++++++++++++++++++++++++++++ Not to brag, but in my experience the Cray-1 would be much harder to find (and maybe more desirable in the long run...)

15 years, 8 months

1
0
0 0

Virtual memory

by roger.holmes＠microspot.co.uk

> From: Dave McGuire <mcguire at neurotica.com> > >>> I'm not familiar with the B5000 implementation (did I miss it in the >>> thread already?), but I did try to avoid restricting the def to that >>> of paging. >> >> The B5000, circa 1961 was an amazing bit of equipment. Read about it >> here, then compare with later systems. >> >> http://www.ajwm.net/amayer/papers/B5000.html The above says the first delivery was in 1963. I believe that is the date which matters. Ideas and plans for computers are around for a long time before they come to fruition and can maybe be traced back for many years but the one date you can rely on is when a customer accepted a machine as working to its specification and paid for it. According to: http://www.chilton-computing.org.uk/acl/literature/news/1962.htm the Ferranti Atlas was working at Manchester University in 1962. I understand it had virtual memory. I wouldn't have wanted to pay for the quarter megawatt electricity bill !

15 years, 8 months

1
0
0 0

Backups in the modern world

by jonas＠otter.se

Tony Duell wrote: > The classic case of that is a demountable hard disk with headcrash > problem. It will damage any disk inserted into it, and those damaged disks > will then casue headcrashes on any other drive they're tried im. > Some indiots end up damaging every head and disk in the building.. That actually happened to a friend of mine years ago. He is/was far from an idiot, just unlucky. The first headcrash was silent, so he did not realize there had been one, put the pack in another drive, went on to copy another pack and moved that one to a third drive. By that time, the first pack had started to destroy the second drive, as witnessed by nasty sounds coming from it. But by then it was too late, the other drives started making nasty noises as well, and 60 heads and three packs had been destroyed. DECs entire stock of replacement heads was exhausted at once and they had to wait for a week while more heads were shipped in and the techs worked repairing the drives. A whole department of programmers was idle for a week. And as I said, the damage wasn't noticeable until after a little while when it was too late. /Jonas

15 years, 8 months

1
0
0 0

AlphaServer 2100

by pontus＠Update.UU.SE

On Mon, Nov 08, 2010 at 11:38:56AM +0000, Peter Coghlan wrote: > If it is not possible to save them all intact, I would be interested in some > CPU and I/O boards and possibly the backplane and memory boards if someone near > the machines is willing to extract boards and ship them to me in Ireland. I > would of course pay for shipping plus a small bonus to you and to the person > shipping them, whatever you think is appropriate. I can ask, it seems to be a nice enough guy. > As a matter of interest, do you have a ballpark price for shipping the > machines intact? A lowball estimate for _one_ machine to me in Uppsala from Lule? is 1300 SEK, but I suspect it will be closer to 2000 SEK. I'll leave conversion as an exercise for the reader. Regards, Pontus

15 years, 8 months

1
0
0 0

AlphaServer 2100

by pontus＠Update.UU.SE

Hi I'm guessing the chance is pretty slim, but if anyone in Lule? or close by wants an AlphaServer 2100 pedistal there are three available for free. They are on the way to the scrapper. I would love to pick these up but they are to far away. If anyone near Uppsala would like to share the shipping costs that would be a possibility. Regards, Pontus.

15 years, 8 months

1
0
0 0

Terak 8510/c Info?

by derschjo＠mail.msu.edu

Hi all - Just got myself a Terak 8510/c workstation, in pretty decent shape. I'm going over it, and preparing to power it up (after testing the power supply). Anyone know any details about this particular model? (And what technical differences there are between the /a and the /c?) There appears to be a good amount of information about the 8510/a, but I can't find a thing about the /c variant. The /c appears to be considerably newer (mine dates from around 1982 and is branded Calcomp on the front), seems to have replaced the single internal 8" drive with two half height 8" drives, and the keyboard and monitor are completely different. A service manual would be extremely helpful -- a few of the double-height QBus cards came loose during shipping and were banging around and I'm not sure yet what the order is supposed to be (I guess I'll have to figure out whether the backplane is serpentine or not... shouldn't be too hard) and it'd be useful to know what the power supply pinouts are so I can test the voltages. And while I'm at it -- has anyone archived any Terak floppies? There's nothing on Bitsavers and I can't find anything anywhere else. Be nice to have some software to run on this thing after I get it running again :). Thanks as always, Josh

15 years, 8 months

4
13
0 0

"Crosspost" of system rescue...

by zmerch-cctalk＠30below.com

As seen on the CoCo list (hosted by MaltedMedia): http://five.pairlist.net/pipermail/coco/2010-November/052008.html In short: 2 each Gimix 6809 multiuser systems, SS-50 based. These are quite rare critters, it would be a shame to see them go. I put a reply on that list & will echo the sentiment here: The systems are in Winnipeg, Manitoba, Canada. The owner says that shipping might be possible to the US *if* they arrange their own Customs brokerage. I'd be happy to help if I can, so even though I live in the US, I'm in a border town (I can see Canada from my bedroom window) so instead of dealing with Customs, if "the lucky rescuer" can arrange shipping to (or near, lets say 50km) Sault Ste. Marie, Ontario, Canada, I'll drive across the border, get the units, bring them into the US [1], and then reship them from the local UPS depot to their destination. [2] [1] As I'm fairly sure the units were made in the US, there *shouldn't* be any duty -- If there's any sticker or documentation that states the fact, that would be much easier to prove. [2] I reserve the right to look at the units for a few minutes -- I remember wanting one of these ever since I saw the ads in Rainbow & HotCoCo... I'll be sure to wear a bib, just in case I drool... ;-) It's much easier to deal with Customs in person, instead of "Hopefully the correct documentation (but probably not) taped to a box (but probably not) and waiting 2-3 weeks for Customs to actually find it (but probably not)." ;-) Winnipeg is about 13-14 hour drive (one way) from where I live, and my pocketbook won't stop hemorrhaging until next February (and something tells me Winnipeg in February ain't the most fun to drive...) so if this were next June, I could prolly find the time (and the $300 in gasoline/petrol) but he's indicated that his timeframe won't allow that. Just tryin' to spread the word, Roger "Merch" Merchberger

15 years, 8 months

2
2
0 0

W00T! SGI is in da house! :oD

by pu1bzz.listas＠gmail.com

Well, this is more than a child?s dream. This THE child?s dream :D Got today an Ozone with 1 proc, 768MB RAM and no hard disks :)))))))))))))))))))))))))))))))))))))))))))))))))) It is working, I already downloaded the Irix install media and found some 36GB HDs that seems to fit :D Just want to share it with you :D :D :D I?m so happy!!! It may be a toy, but I ALWAYS wanted to have a SGI computer :D I even got the original granite SGI keyboard. So bad I wasn?t able to find the matching mouse :( Now I just need to find a proper sled (at least one) for the hard disks. I think I can order one from ebay. W00T!!! I?ll play DOOM on that!!! :D :D :D Uhuuuu! :D Alexandre (happy as a child on xmas with a brand new toy :D) (photos soon, as soon as I have some free time)

15 years, 8 months

3
2
0 0

A3311A SCSI hard drive enclosure - Sleds?

by pu1bzz.listas＠gmail.com

Well, incluiding the HUGE pack of hardware I got today (and the SGI =D) I got an A3311A SCSI hard drive enclosure from HP. How hard is it to find drive sleds? It has three, a pair of 9,1GB drive and a 18GB drive. I want to find at least four drive sleds (ideally 5) so I can put my 4 36GB drives on it, and make it avaiable for the SGI, Ultra 60 or HP9000 BTW, is there such a thing like a SCSI selector, so I can direct the scsi array for one computer or another? Thanks Alexandre

15 years, 8 months

1
0
0 0

commercial scsi target mode product

by aek＠bitsavers.org

http://www.virtualscsi.com/

15 years, 8 months

3
2
0 0

CyberVision 2000

by menadeau＠comcast.net

It was sold by Montgomery Ward, and I believe it is a repackaged RCA system (uses the 1802). I have scans of literature if you want more info. ----- Original Message ----- From: "Bill Sudbrink" <wh.sudbrink at verizon.net> To: <cctalk at classiccmp.org> Sent: Saturday, November 06, 2010 6:03 PM Subject: CyberVision 2000 > Hi, > > > > Anyone know anything about this computer? Google reveals almost nothing. > > According to an email I just received, it was sold in the mid 1970's in > department > > stores around Washington, DC. Email claims before the TRS-80 and Apple > II. > > > > Thanks, > > Bill > >

15 years, 8 months

3
2
0 0

CyberVision 2000

by wh.sudbrink＠verizon.net

Hi, Anyone know anything about this computer? Google reveals almost nothing. According to an email I just received, it was sold in the mid 1970's in department stores around Washington, DC. Email claims before the TRS-80 and Apple II. Thanks, Bill

15 years, 8 months

1
0
0 0

DiscFerret: First working hardware, firmware and microcode!

by classiccmp＠philpem.me.uk

Hi guys, I have -- just this second -- got the standalone, single-board DiscFerret hardware ("0I06") to image a disc. First, the proof: Scatter plot: http://www.discferret.com/temp/dat.scatter.png Histogram: http://www.discferret.com/temp/dat.histogram.png Raw transition data, gzipped space-separated format. First column is array index, second column is the timing value: http://www.discferret.com/temp/dat.gz Rawbinary track dump, gzipped. Most significant bit of each byte is the status of the INDEX sensor (1=index detected). If (x&0x7f) = 0, then a counter carry occurred -- the next byte should have 128 added to it. Repeated counter-carries are allowed.: http://www.discferret.com/temp/dat.bin.gz MagScan analyser output for dat.bin: http://www.discferret.com/temp/dat.magscan.txt For those of you who have a copy of the sources to my Magdecode decoder engine (I know I sent it to at least one person on-list...), the Rawbinary dump should load straight into Magdecode. The space-separated data can be loaded straight into Gnuplot (which is what I used to produce the plots), and I suspect MATLAB and Octave can probably load it too. The image file was created from an old coverdisc from "PC Zone" magazine, and is completely undated on the label. The volume label is "PCZ_OCT_3" which suggests it's from October, with last-modified dates in February and August 1993. It only covers Track Zero, which (if memory serves) is the MBR, FAT and Root Directory. The disc is 720K DOS format, sampled at 40MHz. Other things to note: - The hardware works fine at 80MHz, and possibly faster than that. It should be possible to sample with enough resolution to image a 5Mbps MFM hard disc. - There are plenty of spare registers. The new PIC uses 8-bit multiplexed addressing, which gives 256 register addresses. Only 16 are in use at the moment (!) - Write support isn't enabled yet. I need to port this across from DiscRW and test it (and no doubt rewrite parts of it, as I did with the reader engine). Surprisingly, there are only a few minor issues on the 0I06 PCBs: - C6 is missing a polarity marker. This is a non-issue, as one end connects to the ground plane and the other quite obviously connects to +5V. - Some of the component pads are rather small (notably the inductors and Schottky diodes in the power supply). This makes it hard to heat both the pad and the component pin at the same time, and thus makes the parts a bit of a pig to solder. I worked around this with a hot-air gun, preheater and solder paste... later boards will have bigger pads. - The power supply chip is a QFN with pads under the chip. The only way to solder it down is to use a hot-air gun... unfortunately TI don't make this chip in a more accessible package, and the only viable alternative would have nearly doubled the size of the power supply. Despite these issues, it's perfectly possible to assemble a 0I06 and have it work perfectly, without any "green-wire" fixes. I'm impressed: usually a first-spin board needs at least one track-cut and a couple of green-wires :) Now here's where you guys come in. I really don't want to have boxes and boxes of unused boards and parts hanging around, so I need to know how many people would like to buy a DiscFerret. These would be available as: - PCB only - PCB with the power supply section assembled and tested - Fully assembled and tested PCB - Some other form -- feel free to make suggestions! I'd appreciate it if anyone interested in buying a DiscFerret could email me at philpem at philpem.me.uk, with one of the following in the subject line (start, end, on its own, uppercase, lowercase -- anything will do, my procmail rule is pretty lenient): - "I want a PCB on its own" -- DISCFERRETBARE - "I want a PCB with the PSU built and tested" -- DISCFERRETPSU - "I want the whole thing ready-built" -- DISCFERRETBUILT - "I want a DiscFerret in some other form" -- DISCFERRETOTHER Thanks to everyone who has supported the project thus far -- your thoughts, ideas, comments and criticisms have been very useful! Now to get my reflow oven working and build some prototypes... :) Thanks! -- Phil. classiccmp at philpem.me.uk http://www.philpem.me.uk/

15 years, 8 months

19
58
0 0

TRS-80 Model II Manuals

by nathan＠nathanpralle.com

Thanks to the ever-useful JP Hindin, I've obtained a set of TRS-DOS disks and other application disks for my TRS-80 Model II system, which is the entire setup pictured here, plus a bit more: http://oldcomputers.net/pics/TRS-80-II_table.JPG It's been sitting, covered, pretty much since I obtained it, but now I can try reviving it and actually seeing what it can do. I'm going to tear into it and clean the drives and so forth, document what it has, etc. and then boot 'er up and see what we can see. I'm looking for a copy of the Technical Ref manual for it; despite finding scans of the covers and so forth online, I'm unable to actually locate one. In addition to that, if someone has a Shugart 8" Service Manual, that might come in damned handy for making sure those are up to speed as well. Many thanks, Nathan -- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Nathan Pralle, Computer Geek Email: nathan at nathanpralle.com Web: http://www.nathanpralle.com Blog: http://www.philosyphia.com Twitter: http://twitter.com/NathanPralle -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

15 years, 8 months

26
55
0 0

FF: 2 Maxspeed MaxStations

by g＠kurico.com

Anyone interested in two MaxSpeed MaxStations? One is a SVGA MaxStation and the other a VGA MaxStation. The SVGA version uses a PS2 kb connector, the VGA version an AT kb connector. Sorry, no power supplies. These are free, I'd prefer not to ship, but if I have no local takers then the buyer to pay shipping costs. I'm in Austin TX. These will go to Goodwill if no one is interested. I'm in the very very early stages of shedding the majority of my collection and this is just the start.

15 years, 8 months

1
0
0 0

Virtual memory

by bqt＠softjar.se

On 2010-11-01 00:02, "Chuck Guzis"<cclist at sydex.com> wrote: > On 31 Oct 2010 at 11:37, Johnny Billquist wrote: > >> > The important question here - are the programs aware of the RA >> > register, and can they change it? And can they address the full range >> > of memory addresses as perceived by the program. > No they aren't. Their memory exists from 0 to whatever the field > length is, physically and continously. If they need more, a system > request can expand their field length provided the system has > sufficient physical memory to accommodate them. There is no way > (absent perhaps a system request to get that information) for a > program to know its real physical base address. Ok. So, a program would think it addressed a memory space, which was it's own, and the addresses it used would in no way related to the actual physical memory it ended up referring to. I'd call that virtual memory. Although, having to map the whole virtual memory as one chunk to physical memory makes it a little more work, end less flexible than having pages. And it pretty much prevents you from ever being able to share memory in a reasonable way between processes. >> > Another word for swapping in and out? > But much older and specific to the architecture and not done in > pieces as a tranditional VM swap file would be. Hmm. I don't think swapping is considered to be done in pieces today either, although swapping is also a term that seems to be defined differently depending on which OS we're talking about. Unix systems can both page and swap. Swapping is throwing everything out to disk, including some kernel structures for the process. Don't happen that often nowadays... Paging is normally enough. > I'll take the coward's way out and use the dictionary here: > > "1. Existing or resulting in essence or effect though not in actual > fact, form, or name" > > So my definiton of "fooling the user into thinking he has more > physical memory than he actually has" is certainly valid. > > And the VAX sense is also true, but only if one takes along with it > the ability to over-commit memory space such that the amount of > addressable memory (i.e. the sum of all users' memory) is greater > than the physical memory present. > > A single task running on a VAX with at least as much physical memory > as addressing space would not be using the virtual memory facility-- > every bit is reflected in the presence of real memory. > > But then, we fall on marshy ground again, when we consider the old > "roll/swap" multiuser situation. I can run 8 jobs, each requiring > 65K of memory on a system with 128K physical memory, simply by > selecting when I give each a time slice and swapping/rolling them out > as needed. So is that virtual? Indeed. I remember (not so fondly) running on a PDP-11/70 back in the 80s. The machine was running RSTS/E V7, and the system allows max 63 jobs. We were at times actually 63 users running on that machine, and it only have 1.5M of memory. It was swapping a lot, and things sometimes went slow, but it worked perfectly fine. Seeing a machine today with over 60 users is not common, and I'm not sure it would feel a single bit more pleasant than the RSTS/E system I used back then... And I'd still claim that the memory used by each process was definitely virtual. And I'm willing to continue to fight for that view. Besides, for the PDP-11, that is what DEC called it. :-) Johnny -- Johnny Billquist || "I'm on a bus || on a psychedelic trip email: bqt at softjar.se || Reading murder books pdp is alive! || tryin' to stay hip" - B. Idol

15 years, 8 months

6
11
0 0

PDP 11 Core Memory

by pontus＠update.uu.se

2010-11-05 23:42, Tom Gardner skrev: > > Good eyes! > > When I look more closely, it seems that the X and Y lines are under > the center sections but no cores, ergo, 16 core mats. I'd like to see > a real one to confirm. > > Tom > The reason I noticed is that I looked at a core memory board for a PDP-10 just the other day, it had one half section with missing core. I could take a picture if you like. /P

15 years, 8 months

1
0
0 0

Tek 4051 in Austin

by swtpc6800＠comcast.net

The TEK 4051 is a Graphics Terminal with BASIC in ROM, It used the Motorola 6800 microprocessor. I did a Wikipedia article on the MC6800 and illustrated it with several old advertisements including the first M6800 ad and a Tektronix 4051 ad. Here is the article http://en.wikipedia.org/wiki/Motorola_6800 And here is the TEK 4051 ad. http://commons.wikimedia.org/wiki/File:Tektronix_4051_ad_April_1976.jpg Michael Holley -----Original Message----- From: cctalk-bounces at classiccmp.org [mailto:cctalk-bounces at classiccmp.org] On Behalf Of steve shumaker Sent: Friday, November 05, 2010 2:37 PM To: On-Topic and Off-Topic Posts Subject: Tek 4051 in Austin Tektronix 4051 functioning system??? Austin C/L #2043597225 looks in fair shape.? supposedly working...?? wants $150 cash and? pick up only steve

15 years, 8 months

3
2
0 0

HP9845 design article in EDN

by cclist＠sydex.com

No one seemed to notice this, but I thought I'd post it for Tony's edification. It's a story in the October 7 EDN from the "Tales from the Cube" back section and deals with solving a problem with the I/O board of the HP9845: http://bit.ly/cNwokC (it's a PDF) Enjoy, Chuck

15 years, 8 months

2
5
0 0

MFM and ESDI SCSI bridge boards (was Re: SCSI emulator)

by ethan.dicks＠gmail.com

On 11/5/10, Jules Richardson <jules.richardson99 at gmail.com> wrote: > Dave McGuire wrote: >> On 11/5/10 2:00 PM, Jules Richardson wrote: >>> It's a bit more murky than that (albeit a related issue) because a lot >>> of the bridge boards expect a vendor-specific command to tell them the >>> drive geometry of the attached drive... >> >> MFM- or ESDI-to-SCSI bridge boards (Adaptec ACB-4000, Emulex MD21 if >> memory serves) are weird to begin with... > > I think the Adaptec was one of the most sane boards out there I do have some experience with a couple of them, primarily the ACB-4000 > IIRC it stores > the drive geometry on block zero of the drive at format time, then at > power-on fetches that block back and initialises itself with the loaded geometry. That sounds somewhat familiar to me, but I wouldn't have been able to have said that's what it did without looking it up first. > I can't remember if it just hides the first block from the user, or hides the > whole track. I really can't remember that detail - been way too long, but if I had to guess, I'd guess "block" since I have a fuzzy memory about some detail about moving, say, an ST225 on and off an ACB-4000 and a different kind of controller (an XT MFM card most likely, possibly a WD WX-1 or Everex clone). > I think the board responds to Inquiry, too (although it just returns "ACB > 4000" rather than anything to do with the geometry of the attached drives) That also sounds familiar (having played at the low-level back in my early Amiga days). > I've not played with the Emulex boards - I think the only ones I have are > tape bridges rather than disk. I have a couple of the Emulex bridging boards from the Sun-3/early Sun-4 days, but I never had to set them up - they were black (beige, really ;-) boxes to me. I just stuck them on a Sun box and don't remember any special fiddling. > The Xebec and Omti boards seemed reliable, but their SCSI implementations > were > a little lacking (one of them I think had the option of a user-supplied ROM > with the expected disk geometry encoded into it, but it still wasn't "SCSI > enough" to work with a modern system) I think I tried to fiddle with an Omti board once but didn't achieve enough success to use it. One reason I tried was it was a combo hard-drive/floppy drive model. It would have been handy, but alas no. It's likely I was running into one of those "almost-SCSI" problems and lacked sufficient documentation. Since I moved from PETs and C-64s and small DEC machines first to Amigas and Macs, then much later to PCs, I was very happy when embedded SCSI drives displaced all the Adaptec and Emulex and Xebec and Omti boards - much easier to set up and move from environment to environment. -ethan

15 years, 8 months

3
2
0 0

2026

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

2001

2000

1999

1998

1997

test-drb