test-drb June 2008

test-drb@ccmp.vtda.org

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Free Compaq Portable II (?) from 1986 In Phoenix, AZ

by oldcomputers＠oldcomputers.net

Contact "dan goforth" if interested: godanphx at aol.com

16 years, 1 month

Corestore - the Big Move

by tiggerlasv＠aim.com

>> And FWIW, I am much more >> likely to want to see the computer than the person > > In other words, the photographer would have better engaged your > prurient interest if the person had obscured interesting parts of > the computer, rather than vice versa. Obscuring parts of the computer? With large feather-fans? Grape leaves? How avante-garde. How risque. Yet curiously titillating. Hehe. T

16 years, 1 month

AT&T 3B1 Unix PC

by korpela＠ssl.berkeley.edu

I have one as well. I think mine has the 7300 stamp rather than the UnixPC name. It's got the 8086 coprocessor board to run DOS apps. I have the dev kit, a few OS revs, and a pile of documentation. For it's time it was a pretty decent low-end workstation with a fairly good (non-X11) windowing system. Biggest problem was how slow it was at floating point, probably due to a crappy math library. I don't even think there was an option for a 68881. Since it was designed by convergent, the machine itself it a lot like the Convergent Miniframe (possibly even software compatible). The unix itself was pretty good with virtual memory and memory mapped files, but the max per-process address space was a 2MB which was also the max-RAM supported, IIRC. Eric On Thu, Jun 19, 2008 at 1:57 PM, Mark Tapley <mtapley at swri.edu> wrote: > At 12:04 -0500 6/19/08, Michael Lee wrote: > >> Anyone collect and/or need parts to the AT&T Unix PC? I've got a pile >> of systems I dismantled over a decade ago, and don't really want or know >> how to put back together. >> > > All, > I have a working one, and a fair amount of documentation. I have not > spent enough time with it to be considered any kind of "expert" but I may be > able to answer some questions. Hopefully someone more knowledgeable can pipe > up here. The systems seem pretty cool, although they are kind of rudimentary > as unix workstations. > > Michael, > where are you? I.e. where would shipping be from? > -- > - Mark 210-379-4635 > ----------------------------------------------------------------------- > Large Asteroids headed toward planets > inhabited by beings that don't have > technology adequate to stop them: > > Think of it as Evolution in Fast-Forward. >

16 years, 1 month

IBM 5120 in austin, tx

by frustum＠pacbell.net

A few years back I bought an IBM 5120, then I spent more money collecting some manuals. Sadly, I've never had the time to do anything with it, and I don't foresee doing so. Here is a picture of one and some info, directly from IBM: http://www-03.ibm.com/ibm/history/exhibits/pc/pc_6.html Now, this thing weights a ton (>100 lbs), and I don't feel like packing it and shipping it. It is in Austin, TX. Although I have about $500 sunk into it, I realize that by not shipping it my market is dramatically reduced. Therefore, I'll sell it for $250 if you can come and get it. It boots into BASIC and runs fine. Because I don't have the terminator, and because the internal floppy disks hang off that bus, they floppies won't work until you acquire or build a terminator. The machine also comes with a technical and user manuals, although nothing that isn't already on bitsavers, I believe. There are also four 8" floppies, including a diagnostic disk. Cosmetically it is decent, used but not too yellowed, except for an unfortunate cracked off corner in the rear, which I still have. Despite that defect, it is still a functioning unit.

16 years, 1 month

non-CP/M Z80 board

by ajp166＠bellatlantic.net

> >Subject: Re: non-CP/M Z80 board > From: ard at p850ug1.demon.co.uk (Tony Duell) > Date: Thu, 19 Jun 2008 04:42:01 +0100 (BST) > To: cctalk at classiccmp.org > >> > I think the chips under discussion were the 8085 specialty chips, >> > 8155, 8355, 8755, etc. Got tubes of those? >> >> I've got a dozen or so 8755s, two or three 8155s, and no 8355s. >> Not tube quantities, unfortunately. > >IIRC the 8355 was the mask-progeammed part, so it's not suprising you >don't have any of those, If you did, they proably wouldn't contain the >code you wanted :-). Yes, but it' still useful as an IO device with 16 IO port lines that could individually set for input or output. >The 8755 was the EPROM part, and at least one >version had a quartz windo for erasure (I don't know if there was an OTP >type). The 8155 was RAM. All had I/O as well. There was never an OTP, all were windowed Eprom devices. the 8155 and the '56 were the same device save for CS polarity. they are very useful with 256bytes ram, a programable timer/baud rate generator and 22 IO pins that can be set as output, input or strobned outpus and inputs. >There's also the 8156, which is the same as the 8155 (RAM + I/O) but with >an active-high chip select. Not as common as the 8155. Not as widely used but I have a bunch. >Of course you can use normal RAM and EPROM with the 8085 is you add and >address latch. An 74x373, or the 74x573 which as a saner pinout, is a >common choice. > There was also the 8185 wich was a 1Kx8 ram with muxed address/data. Those were uncommon as intel was the only supplier. The 8085A (or A-5), 8755, 8155 in three chips gave 256bytes ram, 2Kbytes Eprom, 38 configurable port lines, A timer/baudrate generator, 4 interrupt lines and the handy SID and SOD IO pins. Very handy for small applications. The base part ran at 3mhz (3.072mhz) and the faster A-5 was a 5mhz (there were 6mhz HmosII and CMOS parts later). Substitute a 8088 (or V20) and 8284A for the 8085 and you had a 16it cpu with all the Eprom, ram and IO listed. Allison >-tony

16 years, 1 month

CP-M Z80 home brew computer circuit board

by cclist＠sydex.com

Date: Mon, 16 Jun 2008 20:06:07 -0400 From: Allison > I've built my fill of floppy based, IDE based, CF based, ROMdisk based > systems and the latter two are far easier to construct and get going > and if your trying to run CP/M and mess with programming and > applications the smaller lower power SBC can be its own form of fun as > you can put it in a small box with a wall wart and use the laptop as a > terminal anywhere. Having a few PX-8s, Darth Vaders lubch boxes and > S100 systems with all the disks and what not is fine but when you want > to move them it's not so fun using hand truck. Where my tiny Z80 with > 32MB CF in a 5x4x1.5" box is rather fun to bring and show CP/M and > what it can still do, on batteries! You could simply skip the work with soldering iron and implement the same with an emulator on, say, an iPod Touch, with full color graphics, sound and gigs of memory that runs at many times the speed of the Z80. No need for a terminal--program while you're standing in line at the DMV--and no messy sticking things together with bits of hot metal. But then, why do people on this list collect slow bulky old iron that drink power like there's no tomorrow and require careful nursing of ageing components? I submit that they're not collected (for the most part) to do useful work, but rather to recreate an experience or attempt to gain a shadow of one. I remember that my late father started to collect old radios from the 1920s and then abruptly stopped and disposed of his collection. His reason was that "it just wasn't the same". The radio stations didn't broadcast the same programs and he knew that there was better, easier to use equipment with great fidelity and ease of use. And he wasn't the same kid living in a tenement in 1925, scrounging batteries and odds and ends. So, perhaps even though you're not recreating an accurate circa-1978 CP/M experience Allison, it's just as well. We can't go home again. You don't have an audience with a circa-1978 mindset. Today's audiences have been conditioned by what they have around them. CP/M must seem as quaint as a leisure suit or love beads. Me, I miss the big iron. But even if I owned a full 7090 installation or STAR-100 "supercomputer" and could afford the utility bills to run them, there would always be the itch in the back of my skull that a personal computer could run rings around the behemoths-- and be one heckuva a lot quieter and more reliable. Cheers, Chuck

16 years, 1 month

invading varmints

by cclist＠sydex.com

> Date: Sun, 08 Jun 2008 16:07:31 -0400 > From: tiggerlasv > Kind of odd that he was bitten by "several" spiders, > merely by opening a disk drive door. Recluses aren't > at all aggressive, and generally don't go out of their way to attack. > It seems highly unsual that they would "charge out in numbers", > and bite. But, anything is possible. Well, I never met the guy face-to-face and am simply recounting what was told to me by him. We've got spiders all over the place here and generally I've never had any problems with them--they mostly try to flee. On the other hand, I shudder when I think about yellowjackets and stepping on a nest--but I've never run into electronic gear infested by the nasty buggers. Cheers, Chuck

16 years, 1 month

AT&T 3B1 Unix PC

by mtapley＠swri.edu

At 12:04 -0500 6/19/08, Michael Lee wrote: >Anyone collect and/or need parts to the AT&T Unix PC? I've got a pile >of systems I dismantled over a decade ago, and don't really want or know >how to put back together. All, I have a working one, and a fair amount of documentation. I have not spent enough time with it to be considered any kind of "expert" but I may be able to answer some questions. Hopefully someone more knowledgeable can pipe up here. The systems seem pretty cool, although they are kind of rudimentary as unix workstations. Michael, where are you? I.e. where would shipping be from? -- - Mark 210-379-4635 ----------------------------------------------------------------------- Large Asteroids headed toward planets inhabited by beings that don't have technology adequate to stop them: Think of it as Evolution in Fast-Forward.

16 years, 1 month

CP-M Z80 home brew computer circuit board

by cclist＠sydex.com

> Date: Sun, 15 Jun 2008 17:22:48 -0400 > From: "Roy J. Tellason" > I thought it was the 179x parts that had the data separator on-chip, > no? Nope. The 179x require an external data separator, as well as precomp ciruitry and floppy-interface buffering, as well as requiring +12 (although the Fujitsu clones need only +5). It's the 279x that have the internal data separators, but the 1770/72/73 have just about everything in a neat little 28-pin package. About all you have to supply is side and unit-select logic, which is easily done with a write-only latch. Add address decoding logic and you're pretty much done. DMA not required. This contributed hugely, IMOHO, to their being popular on a number of low-end "home" computer systems. The chip handles motor control (e.g. spin-up time from from motor on to ready, auto motor-off after a certain number of inactive revs), which the 179x doesn't do. The 765-based all-in-ones such as the National 8473 and the WD37C65A are about as hard to obtain and are a little more difficult to interface to a Z80 (just about require DMA and interrupts to work right). Cheers, Chuck

16 years, 1 month

CP-M Z80 home brew computer circuit board

by cclist＠sydex.com

Date: Wed, 18 Jun 2008 07:21:35 -0600 From: Les Hildenbrandt <les at hildenbrandt.com> > The 279x (1,3,7) series chips actualy had a working pll data seperator. > Here is a link to the 279x controller chip data sheet: > http://retrotechnology.com/herbs_stuff/fdc_datasheet.pdf > As I recall, the 179x series chips could not reliably do sector reads from > disks formated on a 177x controller. The 179x could do a track read of > the disk. Morrow provided a program with the Disk Jocky controller which > would do track reads, then write the track back out creating a disk which > worked well with either the 177x or 179x series controllers. It was not a > common issue, as very few people used single density once double density > became available, and new single density disks worked well with either > controller. Careful Les--the 177x that you're probably speaking about is the 1771- -the 70/72/73 are very different (and much later) animals with integrated data separators. AFAIK, the 1771 is the only member of your "177x" family. Well, there was the 1781, but that was a very different animal (M2FM) and is very hard to find (I doubt that even Unicorn has them or has ever had them). Fred's right--the 1771 *did* have an on-board data separator, but it was such a joke that even WD discouraged its use. Cheers, Chuck

16 years, 1 month

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test-drb June 2008