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

by ajp166＠bellatlantic.net

> >Subject: Re: Minimal CP-M SBC design > From: "Chuck Guzis" <cclist at sydex.com> > Date: Sat, 10 May 2008 11:27:50 -0700 > To: cctalk at classiccmp.org > >> Date: Sat, 10 May 2008 12:29:24 -0400 >> From: Dave McGuire > >> I dunno Chuck...the only reason more CP/M systems weren't ROM- >> resident back in the day was due to convention, not technical >> restrictions. I (personally) don't think there's anything >> non-"period" about ROM-ing CP/M. > >It's not the ROM-ing of CP/M that disturbs me, but rather the >"disklessness" of the thing. Wasn't the whole idea of CP/M >originally to give you something to manage files on your floppy >drives? I mean, that's what the bulk of the code in CP/M is for-- >heaven knows, the support for other I/O is nothing to write home >about. It would not be diskless only floppy less. > >If one wants to enjoy a "vintage" experience, what sense is there in >being diskless? At any rate, even something as simple as a WD1770- >type controller added to the design would give that capability with a >minimum of support "glue". IF you really want to enjoy the vintage experience you can include a floppy controller but be warned...They are a PAIN to use and program. The most important detail is the unless you include DMA (more parts) the cpu does all the heavy lifiting in real time and that requires tight code or some hardware tricks (more parts). It stops getting simple real fast. Then there are the various floppies with their interface quirks. IDE and CF have simple interfaces, they do not have to be written or read in real time, they are obtailable. FYI reading and writing in real time for a 5.25" DD floppy (seriously anything less than 360K is useless) requires the CPU to fetch/put a byte every 16uS without delay and in somecase the worst case timing for that is 14us. Write a simple routine in Z80 at 4mhz that does that, reliabily. Forget using 1.44MB floppies as doing that in under 8uS is out of the question without a 8mhz Z80, fast ram to support it, fast Eprom and all the other nice things that go with faster. FYI: at 4ux a CPU cycle is .25uS and the shortest instruction is nop at 4 cycles (no wait states) or 1us and a DJNZ is around 7/10 cycles or 1.75uS to 2.5uS... the timing picture is tight. Also there is the problem of getting some FDCs like the 1770,2793 and other more highly integrated chips that aren't 44 pin QFP. >Alternatively, one could stay diskless and add a sound-effects module >to emulate the "chunk" and "grrr" of a head-load and seek--and the >"thunk-click" of a drive door being opened and a floppy inserted. How many more parts do you think you need for that? >I still don't have the hang of this "vintage" thing yet, probably >because I'm vintage myself. Please forgive my density... ;) having built my first Altair in january 1975 and prior to that for work an 8008 when it was new.. what me vintage? Allison

18 years, 3 months

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IBM 129 manual

by paul0926＠comcast.net

I just got my hands on an old IBM 129 keypunch. It seems to power on, but I have no idea how to operate or test it. Anyone know there there might be a manual? I tried all the usual sources (bitsavers, etc) with no luck. I found some old keypunch manuals, but not for this particular model. Thanks. Paul

18 years, 3 months

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Classic Gaming Expo cancelled

by evan＠snarc.net

http://www.cgexpo.com/ Nothing to do with me, just passing along the message.

18 years, 3 months

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Minimal CP-M SBC design

by cclist＠sydex.com

> Date: Fri, 9 May 2008 10:59:35 -0700 (PDT) > From: "Eric Smith" > The lead pitch of shrink DIP packages is 0.070 inch (1.78 mm). I > haven't seen any 0.050 (1.27 mm) inch DIPs. Shrink DIPs were popular > with Japanese semi companies, but never caught on very well with US > companies, most of which skipped those and went straight to PLCC and > PQFP packages. Right you are--I dug out a couple of shrink DIPs and they are indeed 0.070 inch. Unless you're going right to PCB, these are a real pain to deal with today--hard to find sockets, odd spacing, etc. I think I've still got a couple of 64180s in this package kicking around somewhere. Thanks for the correction. Cheers, Chuck

18 years, 3 months

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any STD bus users or developers?

by cclist＠sydex.com

> PCBs with edge connectors really drive the costs up because specialized > prototype boards are required or if you manufacture the PCBs using edge > connectors and gold fingers are extra. It's very strange--at one time Radio Shack (under their "Archer" brand) sold 22/44 position edge-connector prototyping cards, in phenolic, rather than FR4 and with tinned, rather than gold-plated fingers. Vector had similar prototype cards as well. It's kind of hard to believe that they're all gone now, since at one time, they were very common. Cheers, Chuck

18 years, 3 months

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Retro DIY CPUs

by cclist＠sydex.com

Speaking of Z80 build-it-yourself boards, has anyone had any experience with the Russian PDP-11 clone chips, e.g. KH1801BM4? How difficult are they to obtain and how compatible are they with the real thing? The photos of ones that I've seen have date codes in the 90s, so they can't be that rare. Cheers, Chuck

18 years, 3 months

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Serial cable mysteries

by lynchaj＠yahoo.com

Hi, I am working on a home brew SBC and am trying to build a serial cable for it. Are there any RS-232 serial port gurus who could help me plumb out a custom cable? The SBC serial connection works but as it currently is configured it only works as 3 wire serial with no flow control (ie, RD, TD, & GND pins). I would very much like to make the serial cable and SBC support hardware flow control. Having the DSR/DTR pins connected should allow it. However the PC is expecting CTS/RTS hardware flow control. My SBC UART is wired so that the RD, TD, DTR, DSR, and GND pins are brought to the serial connector. I probably should have brought CTS & RTS out but it is too late to change it now. I have wired a cable like this which works for 3 wire serial (no flow control) PC DB25 (9 to 25 pin cable) SBC (25 pin female) 2 TD----------------------RD 3 RD----------------------TD 7 GND---------------------GND 6 DSR---------------------DTR 20 DTR---------------------DSR Obviously this cable does not support hardware flow control because when I try to connect with hardware flow control enabled, I can see the SBC boot message on the terminal screen but cannot send characters from the PC to the SBC. So I have been experimenting trying to figure out how to fix this. I got the data sheet for the 16C550 and a serial port breakout box. After much combinations, I discovered that if I connect a jumper between the PC serial port pins 5 (PC CTS) and pin 20 (SBC DSR) then the serial port *DOES* support hardware flow control. At least it appears to. I get the feeling though that I am mixing dissimilar control signals and it is confusing me. My question is, does the above configuration with the PC CTS and SBC DSR connected really use hardware flow control or is it just "faking out" the PC and/or SBC UART? As a follow on, are both sides actually getting hardware flow control or is it just one side or the other? This is my new and improved serial cable with *appears* to support hardware flow control. Is there any way to test this? PC DB25 (9 to 25 pin cable) SBC (25 pin female) 2 TD----------------------RD 3 RD----------------------TD 7 GND---------------------GND 6 DSR---------------------DTR 20 DTR----+----------------DSR 5 CTS----+ Thanks in advance for any help! Andrew Lynch

18 years, 3 months

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Minimal CP-M SBC design

by ajp166＠bellatlantic.net

> >Subject: Re: Minimal CP-M SBC design > From: Dave McGuire <mcguire at neurotica.com> > Date: Sat, 10 May 2008 12:29:24 -0400 > To: "General Discussion: On-Topic Posts Only" <cctech at classiccmp.org> > >On May 9, 2008, at 12:36 PM, Chuck Guzis wrote: >>> There is no requriement to boot the system from "disk" >>> and making that change can make bring up simpler. >> >> But that's where the "authentic" aspect fails me. Why run a >> "vintage" CP/M system without the experience a disk drive gives you? >> You'll be deprived of the "BDOS Err on B:" messages. What fun is >> that? >> >> One might as well run an emulation program on a PeeCee. I wouldn't >> be at all surpised to find that someone's done it for the iPod Touch-- >> there already exists a NEC 9801 emulator for that platform. > > I dunno Chuck...the only reason more CP/M systems weren't ROM- >resident back in the day was due to convention, not technical >restrictions. I (personally) don't think there's anything >non-"period" about ROM-ing CP/M. Worked for the PX8 and likely a few others. Actually the real and most likely reason is you needed 8k or so of rom and back when Eprom (or enough eprom) that size was a bit later and even then expensive for a while. However by around 84ish 8 and 16k parts were getting reasonable and that is plenty enough space. Besides booting from rom is like booting from disk, the differnce is the rom is read only and doesn't rotate. Oh it is simpler. As to "BDOS Err on B:" you can still have that if the system only boots from rom and still expects a floppy drive (or other removable media). Personally that is one of the error messages that I can do without. ;) Allison > > -Dave >> > > >-- >Dave McGuire >Port Charlotte, FL >

18 years, 3 months

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Minimal CP-M SBC design

by lynchaj＠yahoo.com

> Date: Sat, 10 May 2008 12:29:24 -0400 > From: Dave McGuire > I dunno Chuck...the only reason more CP/M systems weren't ROM- > resident back in the day was due to convention, not technical > restrictions. I (personally) don't think there's anything > non-"period" about ROM-ing CP/M. It's not the ROM-ing of CP/M that disturbs me, but rather the "disklessness" of the thing. Wasn't the whole idea of CP/M originally to give you something to manage files on your floppy drives? I mean, that's what the bulk of the code in CP/M is for-- heaven knows, the support for other I/O is nothing to write home about. If one wants to enjoy a "vintage" experience, what sense is there in being diskless? At any rate, even something as simple as a WD1770- type controller added to the design would give that capability with a minimum of support "glue". Alternatively, one could stay diskless and add a sound-effects module to emulate the "chunk" and "grrr" of a head-load and seek--and the "thunk-click" of a drive door being opened and a floppy inserted. I still don't have the hang of this "vintage" thing yet, probably because I'm vintage myself. Please forgive my density... Cheers, Chuck -----REPLY----- Hi Chuck, I hear what you are saying and agree there is something just very disconcerting about diskless CP/M computers. However, CP/M in the CBIOS is really just about block devices and the OS really could care less whether you attach a 8" SSSD floppy, a CF drive or a ROM. It is all the same to the BDOS. My goal here is to *eventually* allow expansion to include IDE and floppy drives. As a matter of fact, the CBIOS does support IDE hard disks already but requires the interface IO card and the ECB backplane to attach it to the SBC. I have an IDE hard disk with CP/M format and some programs on it. My goal with the SBC using ROM/RAM drives was to allow something minimal to operate as a SBC and have some functionality with the option to expand to as desired. I am trying for a modular, low cost approach with easy to build increments. Assuming I get this SBC respun and into manufacturing my next project is to redo my ECB backplane as a PCB. After that will be the disk IO board and bus debuggers which are also made from prototype boards. My Test Prototype home brew computer was built entirely with prototype boards and point to point wiring. It supported IDE drives and even had a NEC765 FDC circuit built in. I wrote some software but never got around to test the FDC part since the machine started experiencing reliability problems which I think trace back to poor grounding and power distribution issues. The new PCB SBC version seems much more solid than the prototype did. The SBC is something which works but gives only limited functionality. If that is enough, people can stop there. If they want more they can plug it into the ECB backplane and add peripheral cards. So far only two peripheral cards exist; the disk IO card and the bus debugger. Hopefully more in the future. I have some ideas kicking around in my head but am concentrating on the SBC for now. Thanks and have a nice weekend! Andrew Lynch

18 years, 3 months

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IBM 129 manual

by aek＠bitsavers.org

> Anyone know there there > might be a manual? docs now up under http://bitsavers.org/pdf/ibm/cardProc/129

18 years, 3 months

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Minimal CP-M SBC design

by cclist＠sydex.com

> Date: Thu, 08 May 2008 07:50:46 -0400 > From: Allison > I can make the boot process easier as you can plop the rom in > mappable space. The usual arguement is can you get a Z180 > in a package most people are willing to deal with (64pin dip)? I wouldn't want to deal with the DIP as it's a "skinny" DIP with 0.050 pin spacing, unlike, say, the 68K. While it probably makes little difference on a PCB, it requires an adapter if you're prototyping--and sockets are hard to find. It's easier to use the 68 pin PLCC to keep the spacing--smaller footprint too. > The latter is the shadow rom many have refered to. I usualy do that. > And make the rom BIG so not only can I map it in when I want but also > access part of it (ROMDRIVE). I believe the Amstrad Joyce uses the printer controller to force the necessary boot code onto the Z80 bus. (Tony?) At least I've never seen a boot ROM on a Joyce PCB. > There is no requriement to boot the system from "disk" > and making that change can make bring up simpler. But that's where the "authentic" aspect fails me. Why run a "vintage" CP/M system without the experience a disk drive gives you? You'll be deprived of the "BDOS Err on B:" messages. What fun is that? One might as well run an emulation program on a PeeCee. I wouldn't be at all surpised to find that someone's done it for the iPod Touch-- there already exists a NEC 9801 emulator for that platform. > Deblocking is not too mysterious. The real missing bit in the > Alteraion guide is how the BDOS telegraphs the need to preread > and when to skip it. Page 14, section 12 entitled "Sector Blocking and Deblocking" in the Alteration Guide covers it pretty well. I remember being relieved to find the information after I struggled with 1.4 not having any such mechanism. I don't think it was in 2.0 either, but I can check if anyone's curious. Cheers, Chuck

18 years, 3 months

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IMSAI Drive [Imsai original dual 8" disk drive system notes]

by Watzman＠neo.rr.com

The drives used in the original IMSAI disk system were Calcomp 140's (this was with the 2-board IFM/FIB disk controller set). In later versions that supported double density (with the later DIO/PDS 2-board disk controller set), these were changed to identical looking (but electrically different) Calcomp 142's. I have the original Calcomp OEM and service manuals here .... and I have them both in hard copy and as scanned PDF files (someone really lucked out .....). [The drives used by DEC were made for them by Calcomp and had the same faceplate, but I am not sure if they were the same drives or not ... I don't think that they were, but I'm not sure of that.] In the early chassis, Imsai used a Calcomp "PLO" phase locked loop data separator board for each drive (e.g. two of them ... it was a PC board about 4" x 6"). In later chassis, they figured out how to use one single PLO board for both drives. In still later implementations, the PLO was eliminated entirely and data separation was done in the disk controller back in the computer (this did not happen until the DIO/PDS controller replaced the IFM/FIB controller). Also, there was a "short" chassis (early) and a "long" chassis (late). Originally, the chassis had terrible cooling, and a cooling mod kit was developed that consisted of some die-cut cardboard vents and baffles as well as an added fan. The short chassis was too short to house the fan, so when the cooling mod was retrofitted, the fan went on the OUTSIDE back of the case. The later "long" chassis was 2" deeper and had the fan on the inside. In addition to the original Calcomp manuals, I also have an original IMSAI manual on the disk SYSTEM (the original IFM/FIB controller version, not the later DIO/PDS controller version). Unfortunately, I have never scanned that to PDF (it's a bound manual ... I'd have to destroy it). Note that in the original 2-board disk controller, the IFM board went through a lot of revisions, and versions earlier than Rev. 6 were junk. The IFM board is a complete 8080 compute system with it's own 8080 CPU, RAM (2111's, I think) and ROM (two 2708's, I think). I have source code for the IFM firmware, I believe. This board did DMA into the "main" 8080 system memory. It was, for the time, a very elegant design. Unfortunately, it was slow, it REQUIRED the full original CP/M interleave of 6 to work. It was (and therefore is) possible to replace the IFM/FIB controller with a single density Tarbell controller (Western Digital 1771), I did this in a few systems. The result was a MUCH better disk system. In this mod, the PLO board(s) were removed entirely, raw unseparated clock and data were fed back to the [Tarbell single density] controller and the system was 6x faster (could work with no interleave at all), more reliable, lower power and one board instead of two. To do this you put a dip plug into the socket on the Calcomp drives where the PLO had plugged in, that was the only change to the disk box, which connected to the main IMSAI (or other computer) with a 25-conductor flat ribbon cable (DB-25 at both ends). Then you needed a custom cable from a DB-25 socket on the back of the IMSAI to the Tarbell controller, and custom wiring of the Tarbell controller, which was not much more than a "disk controller prototype board" to begin with. I MAY still have my notes on the Tarbell jumpering for that configuration. The may, in fact, be in the PDF file I created of the Tarbell single density manual that was posted on Howard Harte's site.

18 years, 3 months

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Vintage Algorist

by dm561＠torfree.net

--------------Original Message: Date: Fri, 09 May 2008 17:53:43 -0700 From: "Chuck Guzis" <cclist at sydex.com> Subject: Vintage Algorist http://www.apple.com/science/profiles/hebert/?sr=hotnewshttp://www.app le.com/science/profiles/hebert/?sr=hotnews Describes a fellow in Paris who started with an IBM 704 and moved on to various bits of vintage iron to create art. (He uses a Mac now). Tony will appreciate the mention of the HP 98xx series. Cheers, Chuck --------------Reply/Comment: Not "art," but along the same lines and more practical: http://www.engadget.com/2008/03/08/etch-a-sketch-clock-automatically-draws-… m

18 years, 3 months

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WTB: SMC COM81C17 UARTS

by tiggerlasv＠aim.com

Looking for a few SMC COM81C17 UARTS, to repair some vintage computer equipment. This is a 20-pin UART. I don't believe anyone ever made a pin-compatible substitute. Direct replacement only; not interested in any type of kludge. ;-) Shoot me an e-mail if you have some, along with a price. Thanks for your time. . . . T

18 years, 3 months

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Vintage Algorist

by cclist＠sydex.com

http://www.apple.com/science/profiles/hebert/?sr=hotnewshttp://www.app le.com/science/profiles/hebert/?sr=hotnews Describes a fellow in Paris who started with an IBM 704 and moved on to various bits of vintage iron to create art. (He uses a Mac now). Tony will appreciate the mention of the HP 98xx series. Cheers, Chuck

18 years, 3 months

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any STD bus users or developers?

by lynchaj＠yahoo.com

-----Original Message----- From: cctalk-bounces at classiccmp.org [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Jeff Jonas Sent: Thursday, May 08, 2008 9:49 PM To: cctech Subject: any STD bus users or developers? I'm getting the itch to get back to Z80 stuff. Has anyone used the STD bus, or have any parts? I have a few card cages and cards but never enough I/O cards! In the least, I was planning on using the STD bus just for expansion cards to a single board computer. -- Jeffrey Jonas -----REPLY----- Hi Jeff, Have you considered STE or ECB bus rather than the STD bus? STD is a fine bus no doubt but as it uses edge connectors, building prototype boards is more difficult I think. STE and ECB bus use a plain DIN 41612 connectors and can be attached to a plain PCB or prototype board. There are still companies supporting the STE bus (ARCOM and others) and some of the parts are still available. I have found that the selection of the PCB form and bus interface is one of the most difficult selections and factors involved in building homebrew computers. PCBs with edge connectors really drive the costs up because specialized prototype boards are required or if you manufacture the PCBs using edge connectors and gold fingers are extra. Thanks! Andrew Lynch

18 years, 3 months

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Zilog Zeus

by mknoth＠earthlink.net

Hi Tony, thanks for responding! Would you feel comfortable to copy the distribution tape or create a TAR hard disk backup? It would be a great help. I'm working on emulating a Zeus system based on the East German P8000 towers. It would be very interesting to find out how similar this system actually is to your system. As a background - the East Germans could not get their hands on a Zeus system directly due to US export control laws. However, they seem to 've got it anyway - and so their own Z80, Z8000 ICs as well. Did they actually copy the system from somewhere and reverse engineered it or did they write it from scratch no match exactly the original. Those tapes/disk would be great for reference. Cheers, Matt Tony Duell ard at p850ug1.demon.co.uk wrote: > >No real info, alas... > >Zeus was supposedly an acronym for Zilog Enhanced Unix System , or >something similar > >I ahve a Zilog S8000 Model 30 (the large-ish tower machine built in >slices with an SMD hard disk and QIC tape drive). I should have the >(inary) distriution tape for that somewhere, and I hope the hard disk is >still readable (I've not used it for some time, it was fine last time I >used it, and I locked the heads afterwards...). But no source code, or >even full shcemaitcs (YET!). > >-tony

18 years, 3 months

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Interconnecting classic computers

by cclist＠sydex.com

Date: Thu, 8 May 2008 17:32:28 -0400 (EDT) From: der Mouse > I think there must be - below some minimum power, pretty much anything > must go in most bands; otherwise, things like spark plugs in car > engines would be illegal because they splatter a little power all > across the RF spectrum. (Not much power, but pretty much clear across > the band.) Do you mean that you folks outside of the US were spared Ron Popiel and "Mr. Microphone"?! Surely you had his "pocket fisherman"... "It makes the perfect Christmas gift!" Yes, the US does permit unlicensed very low power transmission on the radio broadcast bands. I don't recall if there is a specific power mentioned or simply a propogation distance. Right now, I'm listening to the Beeb World Service on a radio in the bedroom, thanks to a low- power FM transmitter attached to the server downstairs. I don't know if there's a similar provision in UK law, but it might be worth investigating... Cheers, Chuck

18 years, 3 months

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Casio CFX-40

by Randy.Ferrell＠gd-ais.com

I am looking for any working or not cfw-40s. If you have any or any contacts please let me know? Thanks Randy Ferrell I use it daily for enbedded programming.

18 years, 3 months

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PDP-8E diagnostic help needed

by Mark＠Misty.com

Hi, I've got a PDP-8E which I've almost got working. Can anyone here help me figure out this remaining problem? As I examine memory, the address lights count up to 01111, then go back to 00000, instead of 10000. I can manually enter an address higher than 1111, but the 10000 and 100000 bits don't stick -- they go low, as soon as I hit the examine switch to step to the next memory location. I can manually load an address 1000000 or 10000000, and hit examine to see 1000001, 1000010, 1000011, etc..., but once I reach 1001111, it's back to 1000000. It was recommended to me that it might be the carry between E52 and E37, or the E38 input multiplexer for bit 7 (on M8300), so last night I socketed and replaced all three of those ICs, but I still see the same symptoms. I have extender boards, so can access M8300 during operation. I measured the carry line between E52 and E37 go low when I reach 1111, but the light for line 10000 doesn't light on the front panel on the next address, and I see the data from memory location 0000, 0001, etc. repeated, displayed as I continue to step through memory locations, as described above. Of course, if someone has a spare M8300 they would be willing to sell me, that's another option. Mark -- Mark G. Thomas (Mark at Misty.com) voice: 215-591-3695 http://mail-cleaner.com/

18 years, 3 months

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Zilog Zeus

by mknoth＠earthlink.net

Al, this is really cool! Basically the complete system documentation. Would there be a chance that somebody put a dump of the Zeus system at this place? Thanks!, Matt >>used it, and I locked the heads afterwards...). But no source code, or > >even full shcemaitcs (YET!). > >are the documents in >http://bitsavers.org/pdf/zilog/s8000 useful

18 years, 3 months

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Zilog Zeus

by aek＠bitsavers.org

>used it, and I locked the heads afterwards...). But no source code, or >even full shcemaitcs (YET!). are the documents in http://bitsavers.org/pdf/zilog/s8000 useful?

18 years, 3 months

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PDP-8E diagnostic help needed

by gerhard.kreuzer＠liftoff.at

Hi Mark, I have a spare board here in Austria, but its not tested. If you want to have it for test your system, let me know. We will find some smart deal for the shipping costs, I am shure. With best regards Gerhard

18 years, 3 months

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IMSAI Drive

by cclist＠sydex.com

> Date: Thu, 8 May 2008 17:07:25 -0700 (PDT) > From: William Maddox > >From what I can see of it, the doors look a lot like the doors on the > Calcomp disk drives used by DEC for the RX01. If you send me a better > picture of it, or check the labelling on the drives, I might be able to > verify this. There is a fellow in town who quite likely has a scrap > drive -- I've seen a lot of the later RX02s that have been scrapped for > motors and heads in his shop. I've still got the docs for the IMSAI floppy box somewhere and can check to make sure, but I believe the drives are Calcomp 103. Miserable things, compared to the Shugart units. Cheers, Chuck

18 years, 3 months

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Zilog Zeus

by evan＠snarc.net

>>> Gaaah, it's coming back to haunt me! The NJ Computer Museum has a Zilog System 8000 model 21 Just to clarify, Jeff means the MARCH user group's museum, where we host VCF East, etc. ... we've never called ourselves the "NJ Computer Museum". But, he's correct about the Zeus! It was donated by an individual member a couple of years ago.

18 years, 3 months

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Minimal CP-M SBC design

by lynchaj＠yahoo.com

-----Original Message----- From: cctalk-bounces at classiccmp.org [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Jeff Jonas Sent: Wednesday, May 07, 2008 4:23 PM To: cctech Subject: Re: Minimal CP-M SBC design I'm slow to enter the discussion because I'm still busy sorting my z80 parts and single board systems instead of enjoying them :-( I'm of 2 minds regarding the Z80: The "classic" vs. the "embedded" mind-set. The embedded solution: I have a Zilog 50 MHz eZ80 development board with more built-in features that I may ever use: ethernet, InfraRed, a LOT of flash and static RAM. My frustration is the lack of support and community activity despite some high profile contests using the board. A clever fellow made an expansion board that adds 2 compact flash slots so it runs CP/M really fast! That appeals to me since it allows it to run stand-alone even for editing, storing and compiling applications. And there's still the programming/debugging pod for using a host system to debug the system should it require external assistance. Back to the original query: the Zilog ez80 board may be appealing because - it's fast (50MHz) and has a lot built in: MMU, RAM, flash ROM, serial and ethernet ports. - allows much more powerful tools on the host system for source control, compilers, debugging via the pod. - others are using it too The classic side: My first "at home" computer was a Servo-8 single board computer (6 MHz Z80B, 64k ram, 2 serial ports, parallel port, SASI port). I chose that over the 4 MHz Z80A Ampro Littleboard. It cost about $500 (with CP/M and schematics) so I was really hesitant to interface it to my own things until I had some experience with cheaper Z80 systems (particularly since all the parts were soldered in!) Long long ago I breadboarded a 4 MHz z80a with 10K static RAM (intending to use battery backup). I originally intended to use a front panel of LEDs and toggle switches (inspired by the Altair). I gave that up while wiring up all the switches, and instead used a Timex Sinclair 1000 as the front panel (hey, a keyboard and display!) to the dual-port static RAM. (the Timex is a complete Z80 system with just 4 chips: z80 CPU, ROM, RAM and Programmable Logic Array for the rest). I still want to use discrete Z80 chips because - I have a logic analyzer to watch it run (I've disassembled some embedded z80 terminals using it) - I like the way the Z80 family chips interface so directly, even for vectored interrupt mode. - I still want to explore "clever" tricks for memory management such as . using the "M" line to differentiate instruction from data reads . implementing true "cycle stealing" (access to memory not currently active by the CPU). I salvaged many z80 based devices (terminals, modems, terminal servers) and pondered reverse engineering them to reprogram for my own uses. Perhaps I'm too impatient but it seemed easier to just start from scratch, or buy a single board system and work from there. I suspect I'll finally get brave enough to just interface the additional Z80 chips to the Servo-8 Z80B SBC since I like that more than the ez80 (so far). Jeffrey Jonas e-mail: jeffj at panix.com -----REPLY----- Jeff, I am building a Z80 SBC as mentioned previously. If you want to add the Z80 peripherals to a Z80 based SBC, have you considered just building an ECB peripheral card? My Z80 SBC design is based on the ECB bus and supports its optional use. Maybe the best approach is to build of my SBCs and the ECB backplane and you design the peripheral card to go along with it. The Z80 SBC now only supports IO accesses on the ECB. I may extend the design in the next version to allow full memory accesses across the ECB for the next SBC design but so far I don't see much use in it since the SBC already includes 1MB EPROM and 512K SRAM. The ECB pin out is the same but the control logic of the SBC would have to change. In addition, the Z80 SBC supports a IEI/IEO lines on the ECB including a 2200 ohm pull up resistor. The Z80 SBC supports the Z80 open drain /INT line directly to the ECB coupled with a 2N2222 TO-18 transistor to drive it. So far the only device attached to the Z80 /INT line is the 16550 UART. None of the current software uses the /INT line yet since I implemented everything in polling mode only. Maybe this is an opportunity to collaborate? A Z80 PIO/DART board probably wouldn't be too difficult to implement on ECB. Check my website if you are interested. I am using KiCad for EDA which is free software. Please let me know if interested. Thanks! Andrew Lynch

18 years, 3 months

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govliq: what are these things?

by legalize＠xmission.com

Here's a representative lot: <http://cgi.govliquidation.com/auction/view?id=1686038&convertTo=USD> They have descriptions like "General Dynamics signal processor adapter assembly" and they all look like circuit boards with a regular grid and an arrangements of pins placed into the grids. The grids are divided into areas and sometimes color coded. Does anyone have any familiarity with them? There are a ton of these on govliq right now. It seems to be some kind of test harness. -- "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/>

18 years, 3 months

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4
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Autonetics D37 ?

by aek＠bitsavers.org

> I picked up what I believe is a console from an Autonetics model D-37 Minuteman I missile guidance computer. D-37 is a DTL computer for the Minuteman II. There is some info and a picture on Wikipedia now about it.

18 years, 3 months

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Zilog Zeus

by mknoth＠earthlink.net

Hello, does anybody have information/source code/anything about the Zilog Zeus System? It is a System III Unix derivate running on a Z8001 16bit CPU. I'm looking for more infos on that. Thanks, Matt

18 years, 3 months

5
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Interconnecting classic computers

by Arno_1983＠gmx.de

bpope at wordstock.com (Bryan Pope) wrote: > > If you can stand hearing 1070Hz, 1270Hz, 2025Hz, and 2225Hz tones, > > and you're not making too much noise, howzbout: implement Bell 103 > > with modems with microphones and speakers, and just skip the whole > > interconnecting wire business (...) > > I think the cat(s) would take issue with that and proceed to destroy > the cause of said tones... That would probably be an issue even with the ultrasonic setup, ISTR that there were "cat chasers" in the market which issued ultrasound when something entered the detection area of an IR sensor to prevent the fuzzball from going in places where it shouldn't (e.g. near expensive furniture). ard at p850ug1.demon.co.uk (Tony Duell) wrote: > > > It shouldn't be too hard to use a C/L phone as the wireless link=20 > > > between two modems. > > > > I'd be very interested in such an arrangement, but I have the > > suspicion that there will be no convenient location in the handset's > > circuitry to interface a phone line to. > > I suspect if you use 'classic' modems (300 baud, 1200/75, etc), then > it'll e totally trivial if you can also modify the modem. After all, > there are separate Tx and Rx signals inside the modem unit. Yes, but what about the levels? Phone line vs. capsule mic/handset speaker? > > For the DECT system anyway, there are things called "cordless phone > > sockets"; they aren't really cordless as they need a wall wart, but > > they are learned to the base station like a new handset is and present > > Mains is not a problem , given that many of my classic computers also > need it ;-) First of all sorry, I learnt that the correct term is "cordless phone jack". Okay, the whole connection setup would look like that: Comp1 === Modem --- CTJ ))) DECT Base ))) CTJ --- Modem === Comp2. === is RS232, --- is phone line, ))) is DECT transmission. I don't know if that fits your needs, as the modems will probably require some handshaking and they must be used to "dial" the connection (like from one line of a PBX to another). The cordless telephone jacks for the Gigaset DECT system are called "Gigaset 1000 TAE" (or, relabeled: "T-Sinus STA") in Germany, but those have the German TAE-style phone jack. Searching for "DECT cordless telephone jack" should bring up some hits. Beware that some types seem to be trying to be too smart already, I read a manual for a system by TIPTEL where you have to set a switch for fax/modem operation on the telephone jack and the thing emits some sort of negotiation burst ("a short hissing noise") upon pickup when in this mode. Depending on the type, your modem may even need to generate a flash or ground flash signal to put the CTJ into internal dialling mode (don't seize the line at the base station, but ring up another CTJ/handset). With the Gigaset/T-Sinus part you make the distinction by dialling either 0 for external or 9 for internal before the number. > > I see it's hard to make do without permanent cabling, but the ports > > shouldn't be such a problem. You could just run two links into each > > room where > > So I wait for my parents to go out, when they get back they see DB25 > sockets on the walls of most of the rooms :-). Asking beforehand helps a lot I would think ;) At our house, I use every chance when wiring is touched to bring Cat5, RG58 and 2-4 pairs of undedicated copper to pretty much every room - the coax for 10b2 or CCTV, the copper for RS-232, audio, IR-remote-by-proxy, phone or whatever future needs arise. > If the 2 machines are next to each other, I might just run a null-modem > cable between them ;-) I was well aware of that option :) but two links would, for example, enable you to connect two machines which are in the same room, but need protocol analysis or conversion between them done by a third device in a second room. Cheers, Arno -- Arno Kletzander Student Assistant // Studentische Hilfskraft Informatik Sammlung Erlangen www.iser.uni-erlangen.de Der GMX SmartSurfer hilft bis zu 70% Ihrer Onlinekosten zu sparen! Ideal f?r Modem und ISDN: http://www.gmx.net/de/go/smartsurfer

18 years, 3 months

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Peanuts (was: Prepare to chuckle... )

by aek＠bitsavers.org

I hope the person that invented them is burning in Hell right now. Right next to the people who think it's OK to pack something with them, and not BAG the object, so that you end up with shredded static-charged peanut bits in every inacessable crevice of the object.

18 years, 3 months

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Peanuts (was: Prepare to chuckle... )

by cclist＠sydex.com

> Date: Thu, 08 May 2008 10:18:12 -0600 > From: Richard > This isn't the first time someone has made a slam on packing peanuts, > yet I've had plenty of things sent and recieved with peanuts and had > no problems. I think the key is to not just dump the peanuts into the > container, but to physically compress them into the box. The flaps of > the box should require some pressure to fully close around the item. > If done properly, peanuts will not leave a loose void for things to > wiggle around inside. I'll use peanuts to make a "pillow", placing them inside a sealed bag, but never for protecting big or heavy equipment. For that, I use the sheet polystyrene insulation foam sold at home-improvement stores. Above all, I've found that if enough rigid foam is used to prevent the item inside from moving, supporting it on all sides, it most often makes it to its destination without the slightest bit of damage, even through UPS ground. All bets are off, however, if the box gets run over by a forklift, or falls off the conveyor belt while the aircraft is being loaded. I've seen both. Obviously, if there's some loose item in the equipment that will flop around with mechanical shock, it's better to secure it or remove it for separate packaging. I'm not beyond unsoldering wires in order to secure something for shipping if necessary. In my experience, floppy drives, particularly 8" drives, are best shipped with a cardboard insert in place of a diskette and the door mechanism secured with a cable tie. A lot of older hard disks had shipping bolts that could be installed to keep things from moving around with mechanical shock. For the last mile, it pays to be on good terms with your regular UPS/FedEx driver. Cheers, Chuck

18 years, 3 months

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Peanuts (was: Prepare to chuckle... )

by tshoppa＠wmata.com

Richard writes: > This isn't the first time someone has made a slam on packing peanuts, > yet I've had plenty of things sent and recieved with peanuts and had > no problems. I think the key is to not just dump the peanuts into the > container, but to physically compress them into the box. The flaps of > the box should require some pressure to fully close around the item. > If done properly, peanuts will not leave a loose void for things to > wiggle around inside. I think your comments are perfectly valid for the sorts of things that ship well with peanuts. There's even different types of peanuts that work well for different densities of items etc. But they do not work well for dense, heavy items with protrusions that have to be protected. Foam-in-place has a real advantage in keeping the object centered in the middle of the box - compressed peanuts work sometimes but foam-in-place works all the time. And some "handcrafting" with custom wooden or cardboard corner protectors, bubble wrap of appropriate type (some times are best for lightweight items and others will stand the abuse of heavy items) cleverly applied, or even newspaper/kraft paper PROPERLY used can do a remarkable job making sure that it's not the protrusions or corners that hit the edge of the box. It's not so much the peanuts I'm opposed to, they are valuable and sometimes appropriate tools. It's the attitude that throwing a 70 pound, very dense instrument with fragile protrusions into a cardboard box with peanuts around it is the best or only thing that can be done. What's astonishing is that 80% of the time when an instrument was damaged in transit, it was packaged by the "UPS store" or equivalent. You'd think that since they're charging for their services they might actually use UPS-recommended supplies and techniques, but they don't! Tim.

18 years, 3 months

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Minimal CP-M SBC design

by ajp166＠bellatlantic.net

> >Subject: RE: Minimal CP-M SBC design > From: "Andrew Lynch" <lynchaj at yahoo.com> > Date: Wed, 07 May 2008 20:35:10 -0400 > To: <cctalk at classiccmp.org> > > >Hi Andrew, > >Just sitting here wondering why you're not using one of the enhanced- >functioning Z80 chips. Even going with the 64180 or Z180 would give >you 2 UARTS and an MMU, in addtion to 2 DMA channels and a timer. >Later version of this product line, will of course, give you more >instructions and functionality. > >But the MMU can make the whole process of bootup very easy. Simply >use the MMU to map the ROM out after the system's been started >(you've got a 1MB physical address space). Duck soup. I can make the boot process easier as you can plop the rom in mappable space. The usual arguement is can you get a Z180 in a package most people are willing to deal with (64pin dip)? Of course the there is a fast Z180 (33mhz) for those that really want speed. >But if you want to stick with the "real" Z80, I've seen two methods >of getting around the reset to 0000. > >The first is to simply force three bytes onto the system bus to >perform a jump to whatever address you desire after a reset. You'll >only do this once per reset, so the circuitry's pretty simple. > >Another way to is to start out with an EPROM mapped in and then >disable it using an I/O instruction. You can leave RAM mapped in for >write cycles, so that only reads will come from the ROM and writes >will go directly to RAM. That way, you can set up locations starting >at 0000 from a ROM. The latter is the shadow rom many have refered to. I usualy do that. And make the rom BIG so not only can I map it in when I want but also access part of it (ROMDRIVE). >In any case, the ROM needn't be very big. I think Don Tarbell used a >little bipolar 82S123 PROM. Gives you 32 bytes to do what you need, >which, in Don's case was enough to get the first sector of an 8" >floppy read. Maybe but in this day and age a 27C256 makes more sense and you can put the whole system image there and have room left over for a debug monitor. There is no requriement to boot the system from "disk" and making that change can make bring up simpler. > >CP/M BIOSes for 2.2 and below are easy--they're poll-mode with >clearly described inputs and outputs. About the only thing you may >find confusing is the IOBYTE convention, but that's optional and >fairly well documented. IO byte is mostly useful fo when you have moer IO that a console and printer. It's pretty trivial to implement. >>I've written a CP/M BIOS without resorting to assembly, doing the >whole thing in machine code. It's not a big thing and you can start >with the basic set of disk and console I/O routines. There are two >boot entry points in the BIOS jump vector--the "cold start" entered >by a jump to 0000 that (re)loads the entire CP/M BDOS and CCP, and >the "warm start" that simply reloads the CCP. And sources are already on the net for many examples. >Disk I/O is done in 128 byte "sectors", so if your physical sectors >are longer than that, you'll need to set up blocking and deblocking >routines. > >All of this is covered in the CP/M System Alteration guide in pretty >fair detail, along with a couple of samples. Deblocking is not too mysterious. The real missing bit in the Alteraion guide is how the BDOS telegraphs the need to preread and when to skip it. Allison > >CP/M 3.0 or MP/M is more involved, taking advantage of bankswitching. >Interrupt-driven I/O is required for MP/M--and the I/O system is >more elaborate. > >Cheers, >Chuck > >-----REPLY----- > >Hi Chuck, > >Sorry it took me so long to reply. > >There is no good reason as to why my computer is designed the way it is. I >just sat down one day and decided to build a Z80 computer. > >I got a book at the library and did a few Google searches and the next thing >you know I was soldering some parts into a prototype board on my bench. It >went through several interations until I ended up with this design. > >The Z80 is definitely the classic although Zilog makes some much improved >integrated components. Using them would have made life much easier I >suppose but I wasn't aware of them when I started. > >I definitely wanted to avoid the hard to build technologies like SMT or hard >to get parts or unique programmable parts like PALs, GALs, CPLDs, or FPGAs. > >Why? Just because. I could have used those components but in my estimation >they take something away from the "feel" or nostalgia or some other >intangible quality. I am sure Tony probably knows what I am talking about. >;-) I am not sure I do... > >One goal was to make the design easy and cheap so that others could make the >project too and keep it affordable. That pretty much eliminated all the >really modern stuff. > >I did consider PLCC packaging for a bit since it uses 0.1" spaced pins but >decided to stick with plain old DIP chips since they are easier to work with >and test. Yes, PCB density suffers terribly but there is absolutely nothing >practical about this project in the least :-) Why start now? > >Anyway, I am nearing completion of the PCB build process. Last night I got >the machine to boot CP/M from the EPROM. Now it can recognise the ROM and >RAM drives as block devices. > >Allison was a huge help in many of the SBC design aspects and I owe her a >debt of gratitude. > >Thanks and have a nice day! > >Andrew Lynch >

18 years, 3 months

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interactive unix boot disk needed

by g-wright＠att.net

I have a DEC server (PC) with a 486 running Interactive Unix and I cant seem to find a way in to change root Password. Any one have a boot disk or better yet a full set of disks. - jerry Jerry Wright JLC inc g-wright at att.net

18 years, 3 months

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Interconnecting classic computers

by wdg3rd＠comcast.net

> Message: 17 > Date: Tue, 6 May 2008 23:03:50 +0100 (BST) > From: ard at p850ug1.demon.co.uk (Tony Duell) > Subject: Re: Interconnecting classic computers > To: cctalk at classiccmp.org > Message-ID: <m1JtVGL-000J3OC at p850ug1> > Content-Type: text/plain > > > > > Eric Smith wrote: > > > Fred wrote: > > >> If we are going to discuss the WORST systems, surely we can't leave out > > >> the TRS80 casstte port system that RS came up with for classrooms! > > > > > > Well, don't leave us in suspense. In what way was it done badly? > > > Was it unreliable? Did it fail to meet its design objectives? > > > > > > > > > > Our school system had one, back in 1981. > > > > There was a panel that was a mux/demux to 24-ish diskless model 3s. The > > I thought the standard one was for 16 slaves to one host, but there's no > reason for that limit. Sixteen student machines to one instructor station is correct. > I seem to rememebr the same hardware could be used with Model 1s, Model 3s > and Cocos, but that the host and slaves had to e the same type of machine. The first version, the Network 1, was limited to the 500 bps data rate of the Model One interface. Model Ones could be combined with Model 3s and Model 4s, provided the users of the newer machines specified the slow cassette data rate. The Network 2 supported the 1500 bps rate of the Model 3 and 4, the Color Computer line (including the MC-10) and the Model 100/200. 3s and 4s could be mixed at will, all versions of the Color Computer line could co-exist (except the MC-10 -- although the MC-10 used the same data format as the other Color Computers, the BASIC ROM tokenized the keywords in its own unique way, so any BASIC code exchanged would be garbage). The 100 and 200 could be intermixed. I recall hearing about somebody using a Model 4 with its Mod 100 exchange utility getting that combination to work, but I never tried it myself. The Network 1 and 2 were actually rather clever devices for the era. Never gave me a bit of trouble in my classrooms except when some of the students forgot to select the slow speed on their Mod 3s (my first year as an RSCC instructor [starting 2 Nov 1980], the classroom was full of Mod 3s, except of course for the instructor's system). -- Ward Griffiths wdg3rd at comcast.net These histrionics were probably unnecessary, since there was no reason to think anybody would be watching us with more than casual interest until I made my first move to follow Buchanon's trail, in London. Still, somebody might check back this far later, and I always feel that if you're going to play a part, you might as well play it all the way, at least in public -- and it's hard to tell what's public and what isn't, these electronic days. Donald Hamilton, _The Devastators_, 1965

18 years, 3 months

5
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Prepare to chuckle...

by sellam＠vintagetech.com

http://www.vintage.org/blog.php?action=read&pid=22 -- Sellam Ismail Vintage Computer Festival ------------------------------------------------------------------------------ International Man of Intrigue and Danger http://www.vintage.org [ Old computing resources for business || Buy/Sell/Trade Vintage Computers ] [ and academia at www.VintageTech.com || at http://marketplace.vintage.org ]

18 years, 3 months

4
5
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Minimal CP-M SBC design

by lynchaj＠yahoo.com

Hi Andrew, Just sitting here wondering why you're not using one of the enhanced- functioning Z80 chips. Even going with the 64180 or Z180 would give you 2 UARTS and an MMU, in addtion to 2 DMA channels and a timer. Later version of this product line, will of course, give you more instructions and functionality. But the MMU can make the whole process of bootup very easy. Simply use the MMU to map the ROM out after the system's been started (you've got a 1MB physical address space). Duck soup. But if you want to stick with the "real" Z80, I've seen two methods of getting around the reset to 0000. The first is to simply force three bytes onto the system bus to perform a jump to whatever address you desire after a reset. You'll only do this once per reset, so the circuitry's pretty simple. Another way to is to start out with an EPROM mapped in and then disable it using an I/O instruction. You can leave RAM mapped in for write cycles, so that only reads will come from the ROM and writes will go directly to RAM. That way, you can set up locations starting at 0000 from a ROM. In any case, the ROM needn't be very big. I think Don Tarbell used a little bipolar 82S123 PROM. Gives you 32 bytes to do what you need, which, in Don's case was enough to get the first sector of an 8" floppy read. CP/M BIOSes for 2.2 and below are easy--they're poll-mode with clearly described inputs and outputs. About the only thing you may find confusing is the IOBYTE convention, but that's optional and fairly well documented. I've written a CP/M BIOS without resorting to assembly, doing the whole thing in machine code. It's not a big thing and you can start with the basic set of disk and console I/O routines. There are two boot entry points in the BIOS jump vector--the "cold start" entered by a jump to 0000 that (re)loads the entire CP/M BDOS and CCP, and the "warm start" that simply reloads the CCP. Disk I/O is done in 128 byte "sectors", so if your physical sectors are longer than that, you'll need to set up blocking and deblocking routines. All of this is covered in the CP/M System Alteration guide in pretty fair detail, along with a couple of samples. CP/M 3.0 or MP/M is more involved, taking advantage of bankswitching. Interrupt-driven I/O is required for MP/M--and the I/O system is more elaborate. Cheers, Chuck -----REPLY----- Hi Chuck, Sorry it took me so long to reply. There is no good reason as to why my computer is designed the way it is. I just sat down one day and decided to build a Z80 computer. I got a book at the library and did a few Google searches and the next thing you know I was soldering some parts into a prototype board on my bench. It went through several interations until I ended up with this design. The Z80 is definitely the classic although Zilog makes some much improved integrated components. Using them would have made life much easier I suppose but I wasn't aware of them when I started. I definitely wanted to avoid the hard to build technologies like SMT or hard to get parts or unique programmable parts like PALs, GALs, CPLDs, or FPGAs. Why? Just because. I could have used those components but in my estimation they take something away from the "feel" or nostalgia or some other intangible quality. I am sure Tony probably knows what I am talking about. ;-) I am not sure I do... One goal was to make the design easy and cheap so that others could make the project too and keep it affordable. That pretty much eliminated all the really modern stuff. I did consider PLCC packaging for a bit since it uses 0.1" spaced pins but decided to stick with plain old DIP chips since they are easier to work with and test. Yes, PCB density suffers terribly but there is absolutely nothing practical about this project in the least :-) Why start now? Anyway, I am nearing completion of the PCB build process. Last night I got the machine to boot CP/M from the EPROM. Now it can recognise the ROM and RAM drives as block devices. Allison was a huge help in many of the SBC design aspects and I owe her a debt of gratitude. Thanks and have a nice day! Andrew Lynch

18 years, 3 months

1
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govliq: what are these things? (Richard)

by wbblair3＠yahoo.com

> Here's a representative lot: > <http://cgi.govliquidation.com/auction/view?id=1686038&convertTo=USD> > > They have descriptions like "General Dynamics signal > processor adapter > assembly" and they all look like circuit boards with a > regular grid > and an arrangements of pins placed into the grids. The > grids are > divided into areas and sometimes color coded. Does anyone > have any > familiarity with them? There are a ton of these on govliq > right now. > > It seems to be some kind of test harness. The NSN hyperlink links to a page that identifies it as "AN/ALR-69 PECULIAR." The 4920 NSN prefix indicates that it's aircraft maintenance equipment. The AN/ALR-69 Radar Warning Receiver is used in a number of US military aircraft. If that's gold plating in the second photo from the left, these might have some significant recovered metal value. ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ

18 years, 3 months

1
0
0 0

Interconnecting classic computers

by technobug＠comcast.net

On Mon, 5 May 2008 20:55:51 +0100 (BST), Tony Duell wrote: > [...] > Quite often I need to transfer data between 2 machines. Maybe to > download a file from this PC, which I've in turn downloaded from a web > site, to run on one of the classics. Maybe to print out some listing > from > a classic. Whatever. > [...] > > So, I think the problem reduces to 'how to interconnect RS232 > ports'. let > me add some constraints : > Requirements as I understand them: 1 > Must work over a distance longer than the RS232 spec allows (i.e. the > answer is probably not 'A long RS232 cable' :-)). (see <http://www.lammertbies.nl/comm/info/RS-232_specs.html> for an interesting discussion on cable lengths v.s. data rate - your data rates spec'ed below indicate that this is not a problem... 2. > Prefereably no cables at all. One solution I've come up with is to > use a > couple of line drivers and a long cable between them. A long cable > that > my parents, or the cat, will get tangled up in :-( i.e. no cables hence 1 does not apply 3. > No line-of-sight between the machines This excludes optical means. 4. > Must work at 300 and 1200 baud. 110 and 9600 baud would be a bonus 5. > I only need one pair of machines linked at a time. I don't need a > network. [...] Point-to-point - collision avoidance not required. 6. > Must not make use of any flow control lines on the RS232 port, since > some > of my machines don't support them. 7. > Using classic, or at least repairable, hardwre is a bonus :-) 8. > I said 'RS232'. I mean asynchronous serial, of course :-). [...] 9. > I've been looking at some of the license-exempt radio modules, but > they > either are half-duplex or amke use of the flow control lines > (typically > they buffer <n> bytes internally, then de-assert a flow control line > while they pack up that data and send it to the other end). Does this mean that you require full-dupex? ------- If 8 is required, you probably have to go with a dual channel, radio link of some sort. Zigbee is definitely overkill based on 5. A simple set of transceivers should do the trick. TI and others have parts and reference designs. However, my experience has been disappointing in enclosed and partitioned areas with these devices - at least at legal power levels... Item 7 makes me think X10. This is a classic data-over-power-line method that has been around for good number of years. It is generally used to control lights, sprinklers, intrusion alarms, etc. and uses a simple protocol. However, it appears to be half-duplex. The info is out there on the web. You might want to look at ST's ST7540 and ST7538 which are current power-line modems and should do what you want. A small micro to buffer things will probably take care of 6. Jules Richardson noted: > Hmm, I've got a deep mistrust of any 'data over the mains' > technology, but > might that be an option here? I assume *most* of your systems are > physically > plugged into the mains anyway, so it'd meet the ideal requirement > for no extra > cabling. Data rates presumably not lightning fast, of course... I don't think security is of concern here unless you are extremely paranoid or are transferring prohibited material (e.g. perhaps with your collection, ASCII kiddy porn to the impact printer :=P). CRC

18 years, 3 months

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Interconnecting classic computers

by Arno_1983＠gmx.de

ard at p850ug1.demon.co.uk (Tony Duell) wrote: > > Has anybody ever tried interfacing a modem to a cordless phone handset? > > Are cordless phones truely full-duplex, or are they more like > loudspeaking phones whee a local voice input disables the speaker > output? > That is not a problem for voice, of course, but it is for full-duplex > modems. Every one I ever had in my hands was full-duplex, and we started with the analogue generation before we went to DECT. Cordless phones are fun anyway, I recently built a remote power controller for use with an analogue Siemens Megaset base station. (The base station in the ground floor, next to my father's desk, is powered all the time, "picking up" the handset energises a relay that switches on mains for our DSL modem and ethernet hub. Handset is next to my desktop PeeCee in the first floor and powered only when my desktop computer is on. The controller of course also has a local switch wired in parallel, for when my father wants to go online.) > > It shouldn't be too hard to use a C/L phone as the wireless link > > between two modems. I'd be very interested in such an arrangement, but I have the suspicion that there will be no convenient location in the handset's circuitry to interface a phone line to. For the DECT system anyway, there are things called "cordless phone sockets"; they aren't really cordless as they need a wall wart, but they are learned to the base station like a new handset is and present themselves to a phone/fax/modem/whatever like a phone line. Would love to get my hands on one of those one time. > > I believe Tony also has a NetCommander which would let him select which > > Actually I have 3 of them. One is the 16 port model (with 16 RS232 > ports), the others are the fixed-configuration 6 RS232/4 Centronics > models. > > But they do not solce the cabling problem. Nor do they have enough ports > for all my classics... I see it's hard to make do without permanent cabling, but the ports shouldn't be such a problem. You could just run two links into each room where you have machines (to a wall socket), then use temporary cables to connect just the machines on which you are working at the moment (either two in one room, or one in one room, one in another - therefore two links). Cheers, Arno -- Arno Kletzander Student Assistant // Studentische Hilfskraft Informatik Sammlung Erlangen www.iser.uni-erlangen.de Psssst! Schon vom neuen GMX MultiMessenger geh?rt? Der kann`s mit allen: http://www.gmx.net/de/go/multimessenger

18 years, 3 months

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Subject: Interconnecting classic computers

by jeffj＠panix.com

Subject: Interconnecting classic computers > Quite often I need to transfer data between 2 machines ... > My machines vary in size from the pocket computers > up to machines that it's not practical to move. > They're scattered throughout a house. > They are, alas, not in a machine room. > Most of the machines (and all the ones I want to consider for this) > have an RS232 port, either built-in or as an option (which I have). > Most of the machines run kermit. > Or I can simply print to the RS232 port on one machine > and capture the incoming characters on the other That's great: that solves the protocol issue and it's all RS232. > So, I think the problem reduces to 'how to interconnect RS232 ports'. > let me add some constraints : > Must work over a distance longer than the RS232 spec allows > (i.e. the answer is probably not 'A long RS232 cable' :-)). > Prefereably no cables at all. There are D-I-Y kits for that, and pre-made dongles for wireless RS232 using bluetooth or Zigbee. [I got the Circuit Cellar / Freescale Zigbee contest kit but it failed to flash to the wireless modem program that I needed for a project] A "terminal server" puts RS232 ports on ethernet, but I'm unsure if any have builtin WiFi (802.11) or are easy to use via WiFi routers/repeaters. [some are cheap on ebay: I have some but have not gotten to try them. I used some at a previous assignment]. I saw wireless USB in a catalogue, so perhaps a wireless USB to a USB-RS232 adapter might work? I'm suspicious of the USB-RS232 adapters since many are not 8 bit compatible (I learned that the hard way when one won't download to my PIC-18 development system). [and most of the USB stuff I've handled lately works under Linux] > One solution I've come up with is to use a couple of line drivers > and a long cable between them. A long cable that my parents, > or the cat, will get tangled up in :-( You're just reinvented the "short haul modem": a dongle that converts RS232 to stronger signals to travel longer wires, such as RS485 (differential signalling). BlackBox sells them for $$$: http://www.blackbox.com/Catalog/Category.aspx?cid=381,1452,1465 That's why I snagged some fiber optic RS232 adapters: boxes about the size of a pack of cigarettes that converts RS232 to fiber optic (up to 1 km). -- Jeffrey Jonas

18 years, 3 months

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Interconnecting classic computers

by cclist＠sydex.com

Wireless ideas... Serial-to-Bluetooth modules exist, but they're about $50 the each for the bare module, which may be too pricey for a large configuration. Duplex-ness shouldn't be too much of an issue, given a sufficiently generous buffer. Diamond MMC had an interesting card back in the 90's that provided home networking by imposing an RF carrier on the telephone copper pair. I've still got a couple of these cards and they work pretty well. The box claims 10Mb/sec, but reality is more like 1Mb. Still faster than a modem, however. IR was pretty popular for a short time--you could even go around corners if you aimed the transceivers right. It sounds as if Tony just wants to go point-to-point, so there would be only a single transmitter on at any one time. Others have mentioned carrier-current setups, but unless they're pretty sophisticated, low-bandwidth and error-prone. I've got a copy of an article from an issue of the HP Journal back from the 80's, where a spread-spectrum carrier current system is described in detail. I wonder if one could simply buy a carton or two of old 900MHz cordless phones and jerry-rig something up? Come to think of it, I've never even tried interfacing a regular modem to a cordless phone handset. I wonder if it works... Cheers, Chuck

18 years, 3 months

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Minimal CP-M SBC design

by jeffj＠panix.com

I'm slow to enter the discussion because I'm still busy sorting my z80 parts and single board systems instead of enjoying them :-( I'm of 2 minds regarding the Z80: The "classic" vs. the "embedded" mind-set. The embedded solution: I have a Zilog 50 MHz eZ80 development board with more built-in features that I may ever use: ethernet, InfraRed, a LOT of flash and static RAM. My frustration is the lack of support and community activity despite some high profile contests using the board. A clever fellow made an expansion board that adds 2 compact flash slots so it runs CP/M really fast! That appeals to me since it allows it to run stand-alone even for editing, storing and compiling applications. And there's still the programming/debugging pod for using a host system to debug the system should it require external assistance. Back to the original query: the Zilog ez80 board may be appealing because - it's fast (50MHz) and has a lot built in: MMU, RAM, flash ROM, serial and ethernet ports. - allows much more powerful tools on the host system for source control, compilers, debugging via the pod. - others are using it too The classic side: My first "at home" computer was a Servo-8 single board computer (6 MHz Z80B, 64k ram, 2 serial ports, parallel port, SASI port). I chose that over the 4 MHz Z80A Ampro Littleboard. It cost about $500 (with CP/M and schematics) so I was really hesitant to interface it to my own things until I had some experience with cheaper Z80 systems (particularly since all the parts were soldered in!) Long long ago I breadboarded a 4 MHz z80a with 10K static RAM (intending to use battery backup). I originally intended to use a front panel of LEDs and toggle switches (inspired by the Altair). I gave that up while wiring up all the switches, and instead used a Timex Sinclair 1000 as the front panel (hey, a keyboard and display!) to the dual-port static RAM. (the Timex is a complete Z80 system with just 4 chips: z80 CPU, ROM, RAM and Programmable Logic Array for the rest). I still want to use discrete Z80 chips because - I have a logic analyzer to watch it run (I've disassembled some embedded z80 terminals using it) - I like the way the Z80 family chips interface so directly, even for vectored interrupt mode. - I still want to explore "clever" tricks for memory management such as . using the "M" line to differentiate instruction from data reads . implementing true "cycle stealing" (access to memory not currently active by the CPU). I salvaged many z80 based devices (terminals, modems, terminal servers) and pondered reverse engineering them to reprogram for my own uses. Perhaps I'm too impatient but it seemed easier to just start from scratch, or buy a single board system and work from there. I suspect I'll finally get brave enough to just interface the additional Z80 chips to the Servo-8 Z80B SBC since I like that more than the ez80 (so far). Jeffrey Jonas e-mail: jeffj at panix.com

18 years, 3 months

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Interconnecting classic computers

by cclist＠sydex.com

A final wireless thought--if you're going point-to-point, why not an ultrasonic link? It's all within the same structure, right? Cheers, Chuck

18 years, 3 months

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Victor Sirius : which harddisk controller ?

by jos.mar＠bluewin.ch

Does anyone here know the exact type of harddiskcontroller that is used in the Sirius PC ? Jos

18 years, 3 months

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communication between old computers

by les＠frii.com

>If I plug this hypothetical "just works" serial-to-Ethernet box onto >a serial port on an old computer, and plug the ethernet into the >switch along with my desktop computer, laptop, and wireless router, >what exactly should the box do? And what should I, as the user, do? RCPMs used a version of XMODEM which worked over the same port as the console. You would tpye xmodem s/r (send or recieve) and a file name. XMODEM would then use the console port to upload and download the file. You would need a xmodem version for the pc which would support a common protocol.

18 years, 3 months

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govliq: 480 reels of 9-track magtape NIB (Mechanicsburg, PA)

by legalize＠xmission.com

LOT (APPROX 480)BUSINESS SOFTWARE CENTERS INC ENDURA PN 53747 BASF ELECTRONIC DATA TAPE, REEL IS 10 1/ 2" DIAMETER, OPENING 3 5/ 8" DIAMETER <http://cgi.govliquidation.com/auction/view?id=1706742&categoryId=1004> -- "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/>

18 years, 3 months

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Interconnecting classic computers

by technobug＠comcast.net

On Tue, 06 May 2008 07:53:52 -0500 Jules Richardson wrote: >> Jules Richardson noted: >> >>> Hmm, I've got a deep mistrust of any 'data over the mains' >>> technology, but >>> might that be an option here? I assume *most* of your systems are >>> physically >>> plugged into the mains anyway, so it'd meet the ideal requirement >>> for no extra >>> cabling. Data rates presumably not lightning fast, of course... >> >> I don't think security is of concern here unless you are extremely >> paranoid or are transferring prohibited material [...]. > > Ahh, no - on that note I meant 'mistrust' as in reliability. Running > data over > power lines always seems like the sort of thing that'd work in the > lab, but be > a little unreliable out in the real world with all sorts of 'noisy' > devices > plugged into the system. > [...] Actually the X10 home automation system is quite reliable as its longevity attests. Currently, broadband over power is being deployed in a number of test cities in the US (much to the chagrin of Hams - it tends to raise the noise floor in ham bands excessively) and the usual suspects are peddling home networking over the mains (e.g. <http://www.dlink.com/products/?sec=1&pid=561d >). To get around the noise issue, these systems use burst transmission at the zero voltage crossing point when line noise is statistically the least. As I mentioned previously, a number of folks make transceivers for this purpose. Echelon <www.echelon.com> has made their entire business based on this technology used mainly in commercial applications. <http://www.powerlinenetworking.co.uk/component/option,com_frontpage/Itemid,… > is a UK firm pushing the technology locally. IC transceivers are available from ST, Maxim, and SiConnect. The addition of a small micro to do the RS232, support logic, and power supply should make a useable system meeting Tony's requirements. CRC

18 years, 3 months

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Interconnecting classic computers

by dm561＠torfree.net

Has anybody ever tried interfacing a modem to a cordless phone handset? It shouldn't be too hard to use a C/L phone as the wireless link between two modems. I believe Tony also has a NetCommander which would let him select which remote system to connect to and, with a few SS relays, even remotely turn the selected system power on and off. m

18 years, 3 months

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Minimal CP-M SBC design

by dm561＠torfree.net

--------------Original Message: Date: Mon, 5 May 2008 21:21:49 +0000 From: Ethan Dicks <ethan.dicks at usap.gov> Subject: Re: Minimal CP-M SBC design On Mon, May 05, 2008 at 12:10:39AM -0700, Chuck Guzis wrote: > Hi Andrew, > > Just sitting here wondering why you're not using one of the enhanced- > functioning Z80 chips. Even going with the 64180 or Z180 would give > you 2 UARTS and an MMU, in addtion to 2 DMA channels and a timer. I can't speak for Andrew, but for me, I already have this SBC with CPU, some RAM, enough ROM, and a peripheral bus with 5 or 6 PIO chips, all in a package a little smaller than an Apple II PSU. -------------Reply: You might ask on comp.os.cpm; at least one person there claims to have installed CP/M on a printer buffer/sharer. m

18 years, 3 months

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Interconnecting classic computers

by dm561＠torfree.net

-----------Original Message: Date: Tue, 06 May 2008 11:14:08 -0400 From: Sridhar Ayengar <ploopster at gmail.com> Subject: Re: Interconnecting classic computers To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <482075C0.7020507 at gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed M H Stein wrote: > Has anybody ever tried interfacing a modem to a cordless phone handset? > It shouldn't be too hard to use a C/L phone as the wireless link between two > modems. With an acoustic coupler, or with a direct connection? Do cordless handsets carry the entire spectrum of sounds a corded phone does? Peace... Sridhar ---------Reply:----------- I was thinking direct connect; seems to me all you'd need is a small matching transformer and some attenuation. Bandwidth ought to be good for 1200 bd absolute worst case, but I'd be surprised if you couldn't go faster. More research is needed... m

18 years, 3 months

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FS: SGI Iris Crimson

by silent700＠gmail.com

The time has come to move the big red box from my hallway (to make room for other big boxes, of course.) I was going to go straight to ebay but thought I'd offer it up here first. It's marked as a "Server" model but as been upgraded to "Elan" gfx, and I've got the replacement case badge for Elan. I've got one hard drive in there now which boots IRIX but fails looking for other volumes, so consider it ready to reload the OS. RAM is at 256mb. A few pics here: http://flickr.com/photos/chiclassiccomp/sets/72157604070207238/ Pickup only on this one, unless you're *really* serious about owning a Crimson :) I'm in 60074, NW of Chicago. -- j

18 years, 3 months

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duh.... Tektronix 4010 has no microprocessor!

by djg＠pdp8.net

> I can probably coalesce them into a single PDF. How good are the > scans? > I think the scans are pretty good. The combining isn't the issue, I can easily do that. The last step of my scans is to flip though the document checking to make sure the scans are ok for each page, in the right order, remove scanning artifacts etc. Since you have the manual if you want you can do that. If not I will see if I can fit it in this weekend. > I am not sure if my scanner will get some of the larger diagrams all > in one image. > The one I scanned on can do 11x17 which I think fitted the foldout pages.

18 years, 3 months

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Minimal CP/M SBC design?

by tshoppa＠wmata.com

Ethan asks: >From some recent reading of various materials I've been finding >as I do my research, it does seem that a lot of post-S-100 systems >had 56K or 62K of RAM and 2K or 4K of ROM, still. Since I don't >know specifics, let me ask a general question in the hopes that >someone can figure out what machines and answer accordingly... for >those 2K/4K ROM systems, did any portion of those ROMs get accessed >once CP/M was up, or were they vestigal at that point? I can imagine >some sort of monitor program or such being mapped in for when the >OS got lost in the weeds, but what was that ROM space still good for? You mention boot ROM's, but there's more uses that chew up "useful" address space too: A certain fraction of CP/M machines had memory-mapped video and this stopped them (or only through mapping trickery they got there) from having all 64K of RAM available to the user. For example, 24x80 of character-cell video will take up 2kbytes - add some video attribute bits (flash, blink, underline, bold for common video chips), and then the software (which has to be in either RAM or ROM, doesn't matter which because it will eat up some memory space in either event) to drive the memory-mapped graphics and you can have 4K or more taken up by the overhead of memory-mapped video. That 2K or 4K bytes doesn't have to actually eat up user RAM if it is accessed only via I/O space mapping. Some systems made good use of shadow-mapped ROM that was mapped in to do the actual BIOS (disk and terminal I/O) work and then mapped itself back out to give the user more RAM. This only affects a fraction of the "middle-aged" CP/M systems because the oldest assume a real video or hardcopy terminal at an I/O port, and the newest assume that a PC-clone is doing all that work for them, again at an I/O port :-). Tim.

18 years, 3 months

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RM600 mainframe issues

by zampala0＠yahoo.it

Hi, I got a Siemens-Nixdorf Sinix RM600 mainframe consisting of a terminal and two cabinets, the SY53 (Zentraleinheit) and the BG54 (I/O Beisteller). For ease of transport I had to cut a 50-wire cable that was connecting the two cabinets, but now the cable has been put together again. Well, I fire it up and I see on the screen that it's going through a number of tests (cpu, memory, adapters). All is ok till it comes to the booting point. There it fails with the following complains Warning 51763 ios0/scon00 Poll fails. Command response block not valid Warning 33243 ios0/scon00 Controller initialization fails. Command response B SASH error: unable to access SASH root device ios0/sdisk000s0 /stand and it returns a limited SASH shell. Since I am assuming that the ios0/sdisk000s0 device is the hard disk on the I/O cabinet, I guessed that there was something wrong with my home-made replacement of the 50-wire cable. I power it down, go to lunch and get back to find out that, when turned on, random weird characters and symbols are displayed on the screen. It looks like that it entered a sort of editor mode, as it shows a top line in which rows and columns are counted. This top line reads ON LINE | FDXA | R=10 | C=5 | AUX=NONE After a while it hangs. I didn't touch a thing since my almost-ok first boot, I only remember to have played a bit with the console keyboard. Any ideas? shall I call the assistance number at the back of the unit? :-) thanks mirko

18 years, 3 months

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C64 Cartridge disassembly (using MMC Replay w/RR-Net)

by billdeg＠degnanco.com

> >Strange question, but does anyone know how to get a C64 cartridge >case apart without breaking it? I have a bad "Epyx Fast Load" >cartridge, and need a case for my "MMC Replay" w/RR-Net. > >I still haven't really had time to do much with the MMC Replay, I >have managed to get a few things to run from it (the C1541 emulation >is pretty bad). I have managed to successfully get a DHCP lease for >the RR-Net, but haven't gotten it to talk to anything. I finally got >some of my floppies back out of storage (put them up on accident just >before I bought the MMC Replay, and I want to see about making and >writing out D64 images. Zane, If you heat the cart in the oven at a temperature less than that which will melt the case, but enough to melt the glue? I have had considerable adventures with this combo of hardware, here is a link that spells out the steps I took to interface my C128 (in c64 mode) using MMC Replay and RR-Net with the second Ethernet card in a PC formatted with WinXT. I can make a D64 image of a disk in less than 30 seconds. I prefer the c128 because after each image, I get better performance if I restart the C128 using the reset button (rather than have to power cycle the c64). I have a lot of the files you need on my web site, directions and links for the files you'll need are here: http://www.vintagecomputer.net/browse_thread.cfm?id=85 -Bill

18 years, 3 months

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DECserver 90TL...

by ms＠vaxcluster.de

Hello, i found two DECserver 90TL last week at the local flea market. They seem to be in good shape, but i can't find the boot software for them - the file MNENG1.SYS should be all i need... The Digital Networks web site is no more, and after one week of googling and researching i give up: Does anybody where i can find this file? Greetings ms -- Michael Schneider email: ms at vaxcluster.de Germany http://www.vaxcluster.de "Man hat Gedanken, die bleiben ewig d?mlich..." (Campino)

18 years, 3 months

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pdp-8/l supply

by brad＠heeltoe.com

Hi all, I recently obtained an old PDP-8/L in reasonable shape (why does this sound like an AA meeting? :-) Anyway, it doesn't work. So I'm happy debugging. The supplies on the back plane are not right so I decided to pull the main supply. I finally broken down and ordered an ESR meter. Is it smart to check all the caps? I've never used an ESR meter but it seems like a good idea to try it on all the big caps just to see what sort of shape they are in. I assume I need to open the little caps which are in parallel to get a good reading (my experience, limited, is that the little axial electrolytics tend to open/short much more often than the big cans). One of the unregulated supplies (-6) coming off the main transformer was a volt low when loaded and I thought I'd check the caps and the diodes. Unloaded it shows -33v (but looking at the schematic, that may be actually correct. Loaded the +5 was low (like 4.5), unloaded it's perfect (5.01). The lights do light, and run sets the run light, stop stops but load address does not. Worse, it seems to toggle the MA, which is ringing a bell about a common fault. I figured I'd get the supplies all cleaned up first... -brad

18 years, 3 months

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PC Tech Journals to go

by dave＠mitton.com

I offered these once before, but arrangements fell through. I have the following collection of magazines to give for the cost of shipping. USPS Media Mail works best (source zip code 01845) PC Tech Journal 1984 - 1988 1984 V1 n: 8/May,9/Jun 1984 V2 n: 1/Jul,6/Dec 1985 V3 n: 1,2,2,3,3,4,4,5,5,6,7,8,9,10,11,12 1986 V4 n: 1-13 1987 V5 n: 1-13 1988 V6 n: 1,2,3,4,5,6,7,8,10,11,12 1989 V7 n: 1,2,3,4 Extras: PC Products: Jan 84, Jan 85, Feb 85, Jul 85 ---- Dave.

18 years, 3 months

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Minimal CP/M SBC design?

by tshoppa＠wmata.com

Ethan asks: > I am a little unclear, though, about how traditional CP/M systems > were set up for ROM and RAM. Was it common to use a "shadow ROM" > in low mem at reset, then have the BIOS live at the top of memory? > How did 64K RAM CP/M machines handle the BIOS? The most traditional CP/M system has a toggle-in front panel and 16K of RAM, Ethan :-). The much later CP/M systems that had boot ROM's either had them consuming a small amount of high memory permanently with some hardware hackery to jump there on a cold reset, or lived in low mem at reset and had a later stage of the boot process map them out. And I am perplexed by your BIOS question. I think you are using that acronym in a non-CP/M context. If you want to read the "CP/M 2.0 System Alteration Guide" and rephrase your question I think we could make some progress. Tim.

18 years, 3 months

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Minimal CP-M SBC design

by cclist＠sydex.com

Hi Andrew, Just sitting here wondering why you're not using one of the enhanced- functioning Z80 chips. Even going with the 64180 or Z180 would give you 2 UARTS and an MMU, in addtion to 2 DMA channels and a timer. Later version of this product line, will of course, give you more instructions and functionality. But the MMU can make the whole process of bootup very easy. Simply use the MMU to map the ROM out after the system's been started (you've got a 1MB physical address space). Duck soup. But if you want to stick with the "real" Z80, I've seen two methods of getting around the reset to 0000. The first is to simply force three bytes onto the system bus to perform a jump to whatever address you desire after a reset. You'll only do this once per reset, so the circuitry's pretty simple. Another way to is to start out with an EPROM mapped in and then disable it using an I/O instruction. You can leave RAM mapped in for write cycles, so that only reads will come from the ROM and writes will go directly to RAM. That way, you can set up locations starting at 0000 from a ROM. In any case, the ROM needn't be very big. I think Don Tarbell used a little bipolar 82S123 PROM. Gives you 32 bytes to do what you need, which, in Don's case was enough to get the first sector of an 8" floppy read. CP/M BIOSes for 2.2 and below are easy--they're poll-mode with clearly described inputs and outputs. About the only thing you may find confusing is the IOBYTE convention, but that's optional and fairly well documented. I've written a CP/M BIOS without resorting to assembly, doing the whole thing in machine code. It's not a big thing and you can start with the basic set of disk and console I/O routines. There are two boot entry points in the BIOS jump vector--the "cold start" entered by a jump to 0000 that (re)loads the entire CP/M BDOS and CCP, and the "warm start" that simply reloads the CCP. Disk I/O is done in 128 byte "sectors", so if your physical sectors are longer than that, you'll need to set up blocking and deblocking routines. All of this is covered in the CP/M System Alteration guide in pretty fair detail, along with a couple of samples. CP/M 3.0 or MP/M is more involved, taking advantage of bankswitching. Interrupt-driven I/O is required for MP/M--and the I/O system is more elaborate. Cheers, Chuck

18 years, 3 months

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Unable to read unused QIC-40 tapes

by ball.of.john＠gmail.com

A few days ago I finally managed to find and fit a perfect replacement for the pinch roller in my apple 40Mb tape drive. The old roller, like most these days had become a sticky mess and fitting the new one took a half hour with a dremel and a bit of magic with a freezer so that the replacement slipped on and would never come off once it warmed up. Well after watching the thing properly retension a spare QIC-80 tape I had (I have loads of QIC-80 tapes but only a few QIC-40 tapes) I then grabbed an unopened copy of A/UX 1.1 I had been wanting to backup and popped it into the drive and carefully watched it do it's initial retension (like it does whenever a tape is inserted). After a few moments I started to see the tape was not properly spooling back up (it was starting to move up and down on the spool) and I pulled the tape before it ate itself (or at least mashed up the sides of the tape). I fed it another QIC-40 tape and it did it again so I tried the QIC-80 tape again and it didn't happen. The only difference between my QIC-40 tapes and that QIC-80 tape is that the QIC-40 tapes have never been used. Could it be that the drive belts in the tapes are not enjoying me trying to use them after at least 20 years of no use? I won't even risk backing the tape up until I can properly get it to run through the retension cycle properly. More info on the Apple Tape Backup 40SC can be found here: http://docs.info.apple.com/article.html?artnum=704&coll=ap John.

18 years, 3 months

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HPIB Stuff - some capture stuff

by steerex＠ccvn.com

> Thanks for your work on this Steve, I need to find the one or two I > spotted again, but yours was cleaner than mine. > > I tested the PCI NI-Analyser card again on the HP150 - which is the > working HP-IB machine I have. Since I didn't know better I captured > everything again - including timings. For someone writing an emulator, > this could be helpful, but I don't know if you want another huge capture > file of boring Amigo protocol stuff. I've attached what I did and > captures of the analyser interface - I'd welcome your advice on what I > should be capturing that would be useful for protocol understanding. > > Hope all's well and thanks again, > Rodney Brown > Hey Rodney, Hope you don't mind but, I'm gonna post this to the classiccmp list. Someone there may want to follow the discussion. What kind of system are you running the PCI Analyzer on? Windows? Linux? I have FINALLY made some more progress with the ISA GPIB card in my Linux box. Unfortunately, it uses the NEC7210 chip which has been a pain in the rear to program. I found a few snippets of code online but really didn't find anything that directly addressed my needs. I have been able to read and write small data packets to the HP7980 but that's about all. With the tape drive, you have to worry about block sizes, file and record markers, rewind, readahead... Blah... Blah... Blah... As of now, I have not yet figured out how to handle all that stuff. So, I decided to take a break from the tape drive and concentrate on the HPIB CS80 disks. I suspect the HP150 is using the "Cold Load" command to read the tape on bootup. I have not been able to read a tape using that method on my PC (yet). I was already familiar with the CS80 protocol so, I just had to learn to program the 7210 chip. It took a while but, I can finally, with some confidence, program the 7210 to do what I need. I was also able to write some code to support a couple of HP instruments (multimeter / frequency counter) over HPIB. Programming the CS80 disk was fairly easy and, at this point, I can read or write a raw binary file to any partition (including boot) of the HPIB disk from my PC (linux). That disk is then bootable from the HP1000 with a CS80 ROM. I have created a small "library" of sorts with the common CS80 methods and another with the HPIB methods in another. I'm not a "C" programmer so, anyone looking at the code would probably think it's sloppy. But, it works (sorta) :-) The question is: What exactly are your goals at this point? If you're still trying to boot the HP150 off the HP7980, I can probably provide some additional insight into the tape protocol although, I cannot provide any specific info for programming the HP150. One of the problems with programming the tape drive is that you cannot slow down the data interchange to see exactly what it is doing. With the disk there is no "timeout" for any of the transactions. You can slow down (or halt) the bus and watch the interaction between the disk and the computer without causing any errors. You cannot do this with the tape drive. It'll throw an error :-( Furthermore, when the computer boots there is a large chunk of data that is passed across the bus this bloats your analyzer's capture and makes it much harder to pick out the important bits. You might try to capture only the transactions where the ATN is asserted. This will filter out the "data" and only leave the commands to wade through. If you have a HPIB card with the 7210 or 9914 I can perhaps provide some insight into register level programming with those chips. I have not given up on the AMIGO tape protocol. I just have been focused on other stuff :-) There is a steep learning curve when tackling all these protocols at the same time. My suggestion would be to break up the project into smaller chunks. The first thing is to figure out how to do the register level programming on the HPIB card. You will need to know how to send and receive "commands" and "data", how to conduct a "parallel poll", and how to change "states" on the card. The tape and disk protocols are not simple, I would also suggest using a simple device (HPIB meter etc...) to refine you programming. Use the analyzer card to watch the bus to see exactly what happens when a certain chunk of code is executed. Once you get predictable results, it'll be easier to tackle a more complex protocol. Talk to me about the HP150. What HPIB chip does it use? Does your version of DOS/UNIX have the tools that you need to do register level programming? I have HPUX 10.20 on a HP9000/800 that has HPIB support built in. Does the 150 have this kinda support? See ya, SteveRob steerex at ccvn.com

18 years, 3 months

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Whistle Interjet 200(s) available...

by rescue＠hawkmountain.net

These were popular in the day to connect small offices to the net... it combined a mini file server, served as the wan link, mail, etc... These particular 2 units have the sync card and cable for an external CSU/DSU. If there is any interest, fire over an offer... I won't be doing anything with them and they are taking up space... I have one new unit and one demo unit both in their original box with docs and csu/dsu cable. -- Curt

18 years, 3 months

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duh.... Tektronix 4010 has no microprocessor!

by tshoppa＠wmata.com

Richard writes: > I don't know why I never realized this before, but the Tektronix 4010 > graphics terminal is implemented enitrely in SSI TTL logic and > contains no microprocessor. I guess that makes sense with it being > introduced in 1971, but it just suddenly hit me like a brick. My favorite parts of the 4010 are not even SSI TTL. There's a pot you turn up (I seem to recall a Unijunction oscillator) and down to change the baud rate for example :-). > PS: anyone need a 4010 service manual online? I have one and just > noticed it hasn't been scanned on the net anywhere. There was something pretty spastic related to Tektronix and archives of their scope documentation a couple years back, but what you need seems to be online at bitsavers.org right now. You might have to look under "401x" instead of "4010". Wow, 101 Mbytes for what I'm looking at right now! Tim.

18 years, 3 months

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duh.... Tektronix 4010 has no microprocessor!

by djg＠pdp8.net

>> PS: anyone need a 4010 service manual online? I have one and just >> noticed it hasn't been scanned on the net anywhere. > >I think they are somewhere on pdp8.net > ftp://ftp.pdp8.net/misc/4010/ Forgot about them. That was a quick scan for someone who needed it and was going to do some cleanup and put them somewhere better. Looks like that is way overdue.

18 years, 3 months

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Cray2 Construction queries (utterly random)

by jplist2007＠kiwigeek.com

Hey guys; So I'm staring at various pictures of Cray2s and I'm trying to work out what the lower covers are made from. I'm referring to the covers that are coloured, apparently, depending on the install - usually red or blue, but images.google has one with a rather garish yellow/green combination. I'm guessing, for what you paid for a Cray2, you got to pick the colours to match your institute. At any rate, they LOOK like they're puffy, like a vinyl covered foam cushion of sorts, perhaps a nod to the Cray-1 power supply seat covers. Is this the case? Also, are the transparent covers on the inner and outer faces perspex/plexiglass or something different? (I can't imagine real glass, but perhaps polycarbonate? Lexan?) I suppose replies should probably be off-list, given the inanity of the question. Thanks all! - JP

18 years, 3 months

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New to VAX (4000/200)

by rescue＠hawkmountain.net

I am the 'proud' owner of a VAX 4000/200. I have not tried to do much with it yet, first I'll indicate it's config, then my questions (as I'm 'new' to VAX (I admin'd one for a bit 14 years ago... but I deferred to several folk on campus as I was new to admin'ing VMS and I didn't stay in the role long enough to really pick much up)). M9715-AA VAX 4000 internal card (terminates DSSI and SCSI busses) M7626-AA KA660 CPU M7622-AT 16M Memory M7622-BF 8M Memory M3108-PA DSV11-S 2 Line Sync Comm SI-SC 1000 System Industries SCSI card M3118-YA CXA16-M 16 Async Line M3118-YA CXA16-M 16 Async Line M3119-YA CXA08-M 8 Async Line M3118-YA CXA16-M 16 Async Line M7559-00 TQK70 Tape controller are the cards present (from slot 0? (rightmost slot)) And it has 3 DSSI drives, 2 5.25" RF31 (381M) and 1 3.5" RF36 (in one of the 'rail' sets that will support 2 3.5" drives) (1.6G). the 2 RF31s are ID 0 and 1 the RF36 is ID 2 It also has a TK70. Now onto the questions: 1. How is 24M of RAM ? Should I be on the lookout for more ? 2. What releases of VMS, Vax Ultrix, etc should I limit myself to based on 24M and KA660 ? 3. Was there a DSSI version of TK70 ? 4. 4000/200 does not have SCSI, correct ? (other than someone added an SI SC-1000) 5. any idea if a SCSI CD can be booted via the SI SC-1000 ? (boot cmds would be ?) 6. This is supposed to have some version of VMS on it... I have no PW... pointers to 'break in' procedure and password reset ? What is the default sysadmin account as well ? 7. There is what looks like a 50 pin scsi terminator (small size like Sun 411 case) that I've identified as DSSI terminator., What is the 50 pin centronics style connector above that ? 8. What is a DSV11-S good for ? 9. Not that I plan to, but how do you make use of the async cards (they have 50 pin centronics style connectors) 10. Anyone got any more of the 2 3.5" drive mounting assemblies ? 11. Anyone got any RF36 or higher density DSSI drives available ? 12. Can the DSSI drive 'bus' be converted to SCSI ? 13. What is the largest drive/partitions supported on 4000/200 (DSSI or otherwise) ? 14. Have I asked enough questions ? (What have I forgotten to ask :-) ? ) How are the 4000/200 machines ? (Other VAXen I have is VAXStation 2000 and VAXStation 3100, neither of which is running (driveless))... I find the enclosure design pretty cool... and for a large box, has nice design (visually)... (I know it is no SGI... and that it is DEC beige.... but I like the design (doors, badge, etc)). Any drop in cpu/memory upgrades that are worthwhile (in the free to cheap territory of course :-) ). Thanks in advance for any cool info/pointers/etc... -- Curt

18 years, 3 months

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Atari score!

by snhirsch＠gmail.com

I returned from a hamfest yesterday with a mountain of Atari 8bit gear: Atari 800 w/ dust-cover (slight yellowing) (2) 810 diskette drives (2) 1020 Printer/Plotters (1 new in wrapping) 410 Cassette Deck 835 Modem 850 Interface Adapter All original Atari manuals for the above in great condition! All power adapters for the above in working condition. 6 Serial cables Box of assorted joysticks and input devices Huge box of photocopied development tool manuals Still to come as soon as owner unearths them from his basement: Several hundred diskettes SWP ATR8000 CP/M extension system w/ all manuals and software Looks to be a lot of fun getting this stuff up and learning about it. I'm thinking of buying one of the SIO2PC interfaces and the APE software package so I can transfer images from the internet to workable Atari diskettes. Would appreciate any advice or opinions on this. Also, if the owner cannot locate the diskettes, what is the best way to go about bootstrapping things? Where can the various images be found on the net and is APE the best way to do this? Steve --

18 years, 3 months

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by austin＠ozpass.co.uk

For my birthday I received a copy of "The Supercomputer Era" by Sidney Karin and Norris Parker Smith. It's a little hard to track down (my copy is ex. Coleman College Library, La Mesa, California - never checked out!) but provides an interesting, nostalgic look at the state of the supercomputer industry c. 1987. The framework for the book is the (then) shiny new San Diego Supercomputer Centre (SDSC). Much is made of the bleeding edge technology implemented at that site, including dual 50Mbit HYPERnet networking to link their Cray X-MP/48 and SCS-40 to the "Common File System" based around an IBM4381 with a whopping 35GB of online storage (20 GB IBM3380 and a 15GB STC8380 disk drives). With 21 years of hindsight whilst enjoying the book, it's quite sad to read some of the predictions. When written, the Cray 3 with its gallium arsenide seniconductors was tipped for great things, and the ETA-10 at the Von Neumann Centre was expected to conquer all. Knowing the eventual direction the supercomputing field took with massive parallel arrays (and clusters) of scalar processors, I really miss the exotic cool of the old-school vector beasts. Reminds me of the famous Seymour Cray quote: "I'd rather have two bulls pulling my plough than 1000 chickens". It's a great read, anyway, if you can get hold of a copy. As an aside (and to provide a little more meat to this rambling post), whilst reading the above and stopping every 5 minutes to follow something up on the interweb I came across a really interesting website detailing "Great Microprocessors of the Past and Present". Apologies if it's common knowledge or has been discussed at length before, but much of it was new and interesting to me. http://jbayko.sasktelwebsite.net/cpu.html -Austin.

18 years, 3 months

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Minimal CP-M SBC design

by ajp166＠bellatlantic.net

> >Subject: Re: Minimal CP-M SBC design > From: "Joachim Thiemann" <joachim.thiemann at gmail.com> > Date: Sun, 04 May 2008 22:27:36 -0400 > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > >On a tangent, I am curious: how difficult is it to make some form of >CP/M-68k work on a bare-bones 68000 or 68008 system? Long ago, I did >wire up a 68008 system with leftover chips; but my memory is fuzzy. >Can't even remember if the DTACK grounded trick works on the 68008, or >if I forced access times somehow... > >What does CP/M-68k expect in RAM, ROM and I/O locations? > >Joe. NO idea, the sources are on Gaby's site and likely manuals too. Allison

18 years, 3 months

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Minimal CP-M SBC design

by ajp166＠bellatlantic.net

> >Subject: Re: Minimal CP-M SBC design > From: Ethan Dicks <ethan.dicks at usap.gov> > Date: Mon, 05 May 2008 01:25:47 +0000 > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > >On Sun, May 04, 2008 at 09:03:03PM -0400, Andrew Lynch wrote: >> Hi Ethan, I reread your email and thought I'd try to answer some of your >> questions regarding a simple do it yourself CP/M computer. > >Thanks. > >> My first piece of advice is to ask Allison ;-) since she has done this >> dozens of times and can boot CP/M blind folded on a spark gap radio. > >Sure. I was hoping she would chime in. My experience over the years >with CP/M has been somewhat tangental (I've worked on Kapros at work >back in 1980s, I own a couple of Kaypros still, and I've done a little >bit with 22disk and such under MS-DOS), but everytime Allison posts >on CP/M, I learn something. > >> Your basic hardware certainly sounds CP/M capable. I assume that it can >> swap RAM in to the lower pages though, right? CP/M requires RAM at $0000 >> through some address (depends). > >Right. As it stands, the hardware probable cannot do that, but the ace >up my sleeve is that there is a 16V8 GAL that is already wired to important >bus signals so that it can act as the chip select circuit. I was >planning on using one of the output flops as the bootstrap-ROM-enable. >I've done similar sorts of things with MC68000 designs in the past. > >> It likes RAM all the way to $FFFF but can >> live with ROM in the $F000 range. Less RAM than 48K makes things difficult >> though, IMO. > >That's what I was unsure about - but RAM to $EFFF and ROM from $F000 on >up is easy to implement. CP/M doesnt "require" 64K as it's entirely possible to boot and get a prompt with less than 16k. If you wish to run any application with a hint of usefulness you need at least 48k and 56K would be fine so ram to 0f000h serves. I presume the F000h block is rom/Eprom which can be very useful. >> How I implemented my machine was to use a memory configuration latch >> (74LS273)... The schematics are all on my N8VEM page. > >I'll check those out when the sats rise here. > >> A pair of 62256's would work but I prefer a solution using a 512Kx8 SRAM. >> That lets you use the 64K for RAM and the rest for a RAM drive. Whatever >> does it for you though. > >I happen to have some 62256s with me, not any 512Kx8 SRAMs, and the next >plane isn't for almost 6 months. Go with the 32k parts! Hint to save wiring time stack the one atop the other and keep CS/ seperate. Also if you have a 32K eprom you can bank switch that in (do it as low ram/low rom) and you can put CPm and utility stuff in there. >> Writing the CBIOS is actually not that hard. I wrote one more or less based >> on the one in the Andy Laird's CP/M programmers guide book. It was >> recommended by Allison and is *the* reference book AFAIK. CP/M is a great >> OS and is rather portable considering everything it does. > >Hmm... is there a soft copy of that book anywhere? It sounds like the >perfect reading companion. It would be but I know of no on line copy. If you cant cind the on line copies of the bios from teh book I think I have them and can send to pvt email. >> I use 16550 UARTs but the CBIOS abstracts all those details away. I think >> CP/M could care less what sort of serial port you use, even if you use one >> at all. Just implement the CBIOS IO routines and it'll work. Same thing >> for drives; you can use floppy drives, memory, IDE, hard disks, whatever >> from CP/M's perspective they are all block devices. > >Right... but what I _have_ is a choice between a 16550 and a 6402. One >advantage of the 6402 is that its options are hardware selected, so the >bootstrap code doesn't have to do much to be able to squirt out a message >that it's alive. It's probably impractical to put a video circuit on this >design, so I'm going with a serial console in the CBIOS I/O routines >and shifting the burden of display and keyboard input to a dedicated >device. Either will work likely less hardware with the 16550 as it has BRG. >> Best of luck with your project. Let me know if there is anything I can do >> to help! > >Thanks. I still have lots of reading to do, as well as a bit of work to >fiddle up some GAL equations to implement the memory map. It's going to >be somewhat trivial to roll out a 32K RAM/8K ROM design, since there's >already a pair of 28-pin sockets wired up for SRAM and EPROM. The first >big trick will be mounting a second SRAM chip. I do wish I had a 512Kx8 >SRAM with me, but alas, no. > The gal can make life much easier. The larger ramm is nice for MP/M or implementing a soft ramdisk. >I think I have all the parts needed for a ROM emulator, but if not, I >do have a battery-backed 8K SRAM (48Z08?) that I can program in a device >programmer and treat as a ROM for firmware development. At home, I have >a Grammar Engine PromICE, but I didn't happen to haul that along. The ram desive will ge you there. back in the late 70s and early 80s I did it with less (2716 and a home made programmer). > >Thanks for the pointers. I'll check out your project when the 'net >comes up for us. if I can be any help let me know. Allison >-ethan > >-- >Ethan Dicks, A-333-S Current South Pole Weather at 5-May-2008 at 01:10 Z >South Pole Station >PSC 468 Box 400 Temp -69.9 F (-56.6 C) Windchill -103.1 F (-75.0 C) >APO AP 96598 Wind 9.0 kts Grid 41 Barometer 693.6 mb (10119 ft) > >Ethan.Dicks at usap.gov http://penguincentral.com/penguincentral.html

18 years, 3 months

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OT: FIB Microscopy Ideas + Request for 7409

by devonstopps＠gmail.com

We recently had a Focused Ion Beam (FIB) microscopy system installed in our lab - which I've just started to play around with. FIBs are used now fairly widely in the semiconductor industry to modify prototype chips - you can etch or deposit metal/insulator at the 100nm scale. Check out fibics.com for some more info; no relation to me. I wondered if anyone had any neat ideas of what to do with it? Both out of interest, and for a demo for some highschool students who will be here on a Nanotechnology course. I de-capped a ceramic 7401 Quad NAND and a 7405 Hex Inverter - with the idea of modifying the functions. However, I can't think of too much to do with either - except maybe trying to separate the input transistor emitter on each hex inverter to make it function as a NAND. Unfortunately these were the only relatively simple chips I had in ceramic packages - I thought turning a 7409 AND into a 7401 equivalent NAND would be neat for the students to see - and at a scale they could easily work with/understand. Does anyone have any 7409 or 7408, or, a similar ECL, DTL, etc AND in ceramic packages they'd like to give up? Control of the system is fully automated; centered around a IBM PowerPC RS6000 43P running AIX.... T.H.x. Devon

18 years, 3 months

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Minimal CP-M SBC design

by lee＠geekdot.com

> On a tangent, I am curious: how difficult is it to make some form of > CP/M-68k work on a bare-bones 68000 or 68008 system? I've made a BIOS that seems to work and that fits in less than 2K. The thing I can't seem to do is find all the parts to make up a boot image to let me use a CP/M-68K C compiler to compile the sources to the parts I need to make a boot image. > What does CP/M-68k expect in RAM, ROM and I/O locations? It seems to expect to run in RAM, I/O is abstracted through system calls using TRAP #3 > Can't even remember if the DTACK grounded trick works on the 68008, It does. Lee.

18 years, 3 months

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C64 Cartridge disassembly?

by healyzh＠aracnet.com

Strange question, but does anyone know how to get a C64 cartridge case apart without breaking it? I have a bad "Epyx Fast Load" cartridge, and need a case for my "MMC Replay" w/RR-Net. I still haven't really had time to do much with the MMC Replay, I have managed to get a few things to run from it (the C1541 emulation is pretty bad). I have managed to successfully get a DHCP lease for the RR-Net, but haven't gotten it to talk to anything. I finally got some of my floppies back out of storage (put them up on accident just before I bought the MMC Replay, and I want to see about making and writing out D64 images. Zane -- | Zane H. Healy | UNIX Systems Administrator | | healyzh at aracnet.com (primary) | OpenVMS Enthusiast | | MONK::HEALYZH (DECnet) | Classic Computer Collector | +----------------------------------+----------------------------+ | Empire of the Petal Throne and Traveller Role Playing, | | PDP-10 Emulation and Zane's Computer Museum. | | http://www.aracnet.com/~healyzh/ |

18 years, 3 months

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Minimal CP-M SBC design

by lynchaj＠yahoo.com

Hi, all, I was staring at an SBC I have here with a 6MHz Z-80, some ROM, some RAM, and a 26-pin off-board bus for some Z80-PIO boards (this thing was built as a multi-parallel-printer switcher). I've been musing about what it would take to boot CP/M up on this. For user I/O, I was planning on a console serial port and a terminal/terminal emulator. I have IM6402s on hand, but I'd be interested in hearing if certain other chips are preferred, based on what BIOS code is floating around out there. I also have a 16550, but I don't think I have any Z80-SIO chips handy. For mass storage, I was planning on either Compact Flash or an SD card. I think I've seen both as I googled around for modern SBCs. Any of the media I have lying around is plenty large enough (I even have some 4MB CFs and a 2.5MB full-sized PCMCIA flash card on hand). I am a little unclear, though, about how traditional CP/M systems were set up for ROM and RAM. Was it common to use a "shadow ROM" in low mem at reset, then have the BIOS live at the top of memory? How did 64K RAM CP/M machines handle the BIOS? Did they temporarily ghost the ROM on top of RAM until some bit of code could read ROM and write RAM then bank out the ROM? Since I think I "need" at least 48K of RAM, I was planning on a pair of 62256s. I could easily do 56K of RAM low and 8K of ROM high, I think, unless there's some other arrangement that's obvious to try for a simple design. I've never tried writing a BIOS for a CP/M machine, but my understanding is that things are modular enough that once you know what I/O chips you have and at what I/O addresses, for a straightforward, non-clever design, the coding is equally straightforward and non-clever (but please feel free to enlighten me if otherwise). Thanks for any tips, especially from anyone on the list who has ever rolled their own CP/M machine. -ethan -- Ethan Dicks, A-333-S Current South Pole Weather at 4-May-2008 at 19:40 Z South Pole Station PSC 468 Box 400 Temp -74.2 F (-59.0 C) Windchill -105.4 F (-76.4 C) APO AP 96598 Wind 7.4 kts Grid 77 Barometer 691.6 mb (10194 ft) Ethan.Dicks at usap.gov <http://www.classiccmp.org/mailman/listinfo/cctalk> http://penguincentral.com/penguincentral.html ________________________________ -----REPLY----- Hi Ethan, I reread your email and thought I'd try to answer some of your questions regarding a simple do it yourself CP/M computer. My first piece of advice is to ask Allison ;-) since she has done this dozens of times and can boot CP/M blind folded on a spark gap radio. Seriously. She is amazing and has helped me many times. Mucho Thank you Allison! Your basic hardware certainly sounds CP/M capable. I assume that it can swap RAM in to the lower pages though, right? CP/M requires RAM at $0000 through some address (depends). It likes RAM all the way to $FFFF but can live with ROM in the $F000 range. Less RAM than 48K makes things difficult though, IMO. How I implemented my machine was to use a memory configuration latch (74LS273). On reset, the ROM is swapped in to the lower 32K page. There is a fixed page of RAM in the upper 32K page. The ROM loader program does some simple copying of data from the ROM to the upper RAM page. Then it writes to the memory configuration latch to swap out the ROM and have a full 64K RAM. The whole thing is amazingly simple. The schematics are all on my N8VEM page. A pair of 62256's would work but I prefer a solution using a 512Kx8 SRAM. That lets you use the 64K for RAM and the rest for a RAM drive. Whatever does it for you though. Some people like the dual 62256's and it does simplify the circuit a bit. Writing the CBIOS is actually not that hard. I wrote one more or less based on the one in the Andy Laird's CP/M programmers guide book. It was recommended by Allison and is *the* reference book AFAIK. CP/M is a great OS and is rather portable considering everything it does. I use 16550 UARTs but the CBIOS abstracts all those details away. I think CP/M could care less what sort of serial port you use, even if you use one at all. Just implement the CBIOS IO routines and it'll work. Same thing for drives; you can use floppy drives, memory, IDE, hard disks, whatever >from CP/M's perspective they are all block devices. Best of luck with your project. Let me know if there is anything I can do to help! Andrew Lynch

18 years, 3 months

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duh.... Tektronix 4010 has no microprocessor!

by legalize＠xmission.com

I don't know why I never realized this before, but the Tektronix 4010 graphics terminal is implemented enitrely in SSI TTL logic and contains no microprocessor. I guess that makes sense with it being introduced in 1971, but it just suddenly hit me like a brick. PS: anyone need a 4010 service manual online? I have one and just noticed it hasn't been scanned on the net anywhere. -- "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/>

18 years, 3 months

2
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13W3 -> 3 BNC

by alexandre.laguejacques＠gmail.com

You know what, I figured it out. I looked to see if there was anything printed on the cable, and guess what: "Solbourne Computer Inc". I believe that they manufactured some Sparc clones? In any event, it's definitely a 3 BNC cable and not a 4 BNC. - Alex Alexandre Lag?e-Jacques alexandre.laguejacques at gmail.com

18 years, 3 months

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Minimal CP/M SBC design?

by ajp166＠bellatlantic.net

> >Subject: Re: Minimal CP/M SBC design? > From: "Roy J. Tellason" <rtellason at verizon.net> > Date: Sun, 04 May 2008 16:22:33 -0400 > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > >On Sunday 04 May 2008 15:57, Ethan Dicks wrote: >> I am a little unclear, though, about how traditional CP/M systems >> were set up for ROM and RAM. Was it common to use a "shadow ROM" >> in low mem at reset, then have the BIOS live at the top of memory? >> How did 64K RAM CP/M machines handle the BIOS? Did they temporarily >> ghost the ROM on top of RAM until some bit of code could read ROM >> and write RAM then bank out the ROM? Since I think I "need" at >> least 48K of RAM, I was planning on a pair of 62256s. I could easily >> do 56K of RAM low and 8K of ROM high, I think, unless there's some >> other arrangement that's obvious to try for a simple design. > >I have some amount of docs on that stuff scattered here and there, and am not >real clear at the moment just where it's all located. I do recall some >stuff, though. One that comes to mind had the ROM (or EPROM?) mapped in at >reset, and one of the coldstart initialization routines copied some small >portion of that up into high RAM. I know that the Osborne Executive had >3 "banks" one of which had the eprom and video RAM mapped into it. I think >that some of the TRS-80 machines needed a special version of CP/M because >they had ROM in low memory and no way to map it out. There were probably >other variations I'm not thinking of besides. There were also mod kits for the trs80 to relocate not only the rom but video and keyboard which were also in low ram. >> I've never tried writing a BIOS for a CP/M machine, but my understanding >> is that things are modular enough that once you know what I/O chips >> you have and at what I/O addresses, for a straightforward, non-clever >> design, the coding is equally straightforward and non-clever (but please >> feel free to enlighten me if otherwise). > >That's my understanding of it too, though the mechanics of actually putting >together a bootable CP/M system are something I'm still a bit fuzzy on. I >probably oughta do that with my BBII one of these days. I can walk you thorugh it. It really helps to have a PS with a SIM/emulator like MYz80 or for this and better is Dave Dunfields NS* horizon emulator. Reason for that is it makes a good development environment, sources you will need are in the IMD collection for it. For a PC running something like W98 (later works once you fight with the OS IO) you can have the simulated Horizon even serial download code from inside CP/M! The basic process is to gen (movecpm) up a image of CP/M for the correct memory size (usually the higest ram address - the size of the bios) and then take a snapshot of the CCP and BDOS. OR you can get the sources and run them through ASM for the correct memory size. the result is the same a BIN file of 5.5K that has a specific load address. Then you can copy a bios and alter it for your IO The console IO is by far easiest and the disk (or the disk equivilent) will be a bit more complex. Once you have a BIOS that can assemble you put the whole mess in a Eprom (orEEPROM) with a small snippet of code to copy it from ROM to ram at the correct address and jump to the "COLDBOOT" entry in the BIOS where the code will Kill rom, init low ram, log in the default disk and put up the intro screen and prompt. here are bits and peices I didn't explan but that the overall path. FYI: while older systems booted the system from disk there is no requirement nor need for that. If there is enough rom (8k will do) you can put the whole image in there plus the copy block code. >I have a fair pile of downloaded files pertaining to this and other >CP/M-related stuff, what used to be that portion of the files section on my >old BBS on hand here, I can send you a list of what's there off-list if you >like. Most are online with Gaby's http://www.cpm.z80.de/ The Unofficial CP/M site and likely the most complete archive out there. You can get most everything you need there and if not the Links are there to the best of the best. Allison >-- >Member of the toughest, meanest, deadliest, most unrelenting -- and >ablest -- form of life in this section of space, ?a critter that can >be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters" >- >Information is more dangerous than cannon to a society ruled by lies. --James >M Dakin

18 years, 3 months

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Minimal CP/M SBC design?

by ajp166＠bellatlantic.net

> >Subject: Minimal CP/M SBC design? > From: Ethan Dicks <ethan.dicks at usap.gov> > Date: Sun, 04 May 2008 19:57:05 +0000 > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > >Hi, all, > >I was staring at an SBC I have here with a 6MHz Z-80, some ROM, some RAM, >and a 26-pin off-board bus for some Z80-PIO boards (this thing was built >as a multi-parallel-printer switcher). I've been musing about what it >would take to boot CP/M up on this. Review: For cp/m usable [runs apps not merely boot] system you need. -Z80 any speed. -56->64K of ram, more is meaningless unless yoru running MPM. Ram must be from 0000h through at least 32k preferably EFFFH as most useful apps want 48-56k. -Boot rom and shadow logic. -Mass storage (anything that can be made to look like block addresable storage.) - console device maybe simple RS232 to terminal(PC with term emulation) - printer is optional. - punch and reader devices are rarely needed/implemnted That is in as fwe words as possible. > >For user I/O, I was planning on a console serial port and a terminal/terminal >emulator. I have IM6402s on hand, but I'd be interested in hearing if >certain other chips are preferred, based on what BIOS code is floating >around out there. I also have a 16550, but I don't think I have any >Z80-SIO chips handy. If you look there will be a bios for most every thing and none will match your IO 100% due differnt addresses or disk(or disk equivilent) used. However.. they can serve as a template. FYI: a good low parts count IO would be Z80, Z80 CTC (as baud rate gen) and Z80sio(or DART). Then you can use the AmproLB and others IO for serial and two ports are handy. > >For mass storage, I was planning on either Compact Flash or an SD card. >I think I've seen both as I googled around for modern SBCs. Any of the >media I have lying around is plenty large enough (I even have some 4MB >CFs and a 2.5MB full-sized PCMCIA flash card on hand). CF is the easiest as the interface is IDE with one feature it does do 8bit transfers. To match the tiny card you can get CF to IDE adaptors with .100 pin (40 pin) cable IO. As to how much CPM can adress logical drives to 8Mb and a 32MB CF is 9$ and would partition into 4 drives nicely. >I am a little unclear, though, about how traditional CP/M systems >were set up for ROM and RAM. Was it common to use a "shadow ROM" >in low mem at reset, then have the BIOS live at the top of memory? >How did 64K RAM CP/M machines handle the BIOS? Did they temporarily >ghost the ROM on top of RAM until some bit of code could read ROM >and write RAM then bank out the ROM? Since I think I "need" at >least 48K of RAM, I was planning on a pair of 62256s. I could easily >do 56K of RAM low and 8K of ROM high, I think, unless there's some >other arrangement that's obvious to try for a simple design. The BIOS needs to be in high ram for the simple case and usually copied there at boot time. So the boot is rom at 0000 (or made to appear there for boot) you copy to high ram then kill (shut off rom) using an IO port bit. Generally for simplest systems I use 16 or 32K eproms as there is plenty of space and I can put a monitor and a complete image of CP/M (CCP 2k, BDOS 3.5k, BIOS typically 1k to 4k). For somthing kike CF a BIOS will easily fit in 2.5K so the whole CP/M system image is 8K. >I've never tried writing a BIOS for a CP/M machine, but my understanding >is that things are modular enough that once you know what I/O chips >you have and at what I/O addresses, for a straightforward, non-clever >design, the coding is equally straightforward and non-clever (but please >feel free to enlighten me if otherwise). That's it. Interrupts or other features complicate it some but look at the CP/M alteration guide for the MDS800 bios example and the Skelental Cbios. FYI: Cbios is the term for anything other than the "stock" MDS800 bios with means just about every bios going! For other example BIOS look up these as I know they are on line: Compupro AmproLB Hal Bower B/P bios (very sophisticated bios) Andy Johnson-Laird (The CP/M programmer handbook) Both the basin bios and the enhanced bios from the book are on line somewhere And many others. The bios has a standard layour and defined functionality. > >Thanks for any tips, especially from anyone on the list who has ever >rolled their own CP/M machine. I've rolled more than a few. If you need info I can help. Allison >-ethan > >-- >Ethan Dicks, A-333-S Current South Pole Weather at 4-May-2008 at 19:40 Z >South Pole Station >PSC 468 Box 400 Temp -74.2 F (-59.0 C) Windchill -105.4 F (-76.4 C) >APO AP 96598 Wind 7.4 kts Grid 77 Barometer 691.6 mb (10194 ft) > >Ethan.Dicks at usap.gov http://penguincentral.com/penguincentral.html

18 years, 3 months

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blogpost: Tektronix terminals and Apollo DN10000

by jules.richardson99＠gmail.com

Ken Seefried wrote: > From: Jules Richardson <jules.richardson99 at gmail.com> >>> >>> As I understand it, the DN10K uses a custom RISC processor and not a >>> 680x0. >> >> Indeed - a88k (not to be confused with m88k) wasn't it? > > Not m88k. Totally custom job called PRISM. No, not m88k. I've always seen them referenced as a88k (to distinguish from m88k!), but I'd forgotten that PRISM was also an official name for them... Surprisingly, there's actually a wiki article about the processor: http://en.wikipedia.org/wiki/Apollo_PRISM cheers Jules

18 years, 3 months

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govliq: 125+ NIB 9-track tapes (Richmond, VA)

by legalize＠xmission.com

<http://cgi.govliquidation.com/auction/view?id=1713966&convertTo=USD> -- "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/>

18 years, 3 months

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8251 troubles

by cclist＠sydex.com

Date: Tue, 29 Apr 2008 17:49:41 -0700 From: dwight elvey > Still a strange problem. This is past the point where I'd have my logic probe out (if you don't have one, they're easy enough to make)--and this is a perfect application for one, as the signals aren't super-fast. Bring your test up, send a character to get the software into the state where it quits receiving. Let's check the static signals first. Is pin 22 (DSR/) low? If not, check your "null modem" cable and any level conversion logic upstream from that pin. While you're at it, check that pin 23 (RTS/) is low so that you can transmit when the time comes. Now for the dynamic tests. A logic probe with a "pulse stretcher" is needed here. Fortunately, most have this feature. Next, put a probe on pin 3 (RxD) and make sure that it's pulsing with each character sent. And then check pin 14 (RxRDY). Does it pulse high with each received character? If it goes high with the first and stays high, then you're not retrieving characters after the first. But if it pulses high only once and then stays low, check your chode. Somehow, you're disabling the receiver, perhaps as part of the "TOUT" code. (This is bit 2 of the command word and must be set for the receive side to operate). The third possibility, that RxRDY pulses with each received character, says that you're actually picking up the data and it's not getting echoed back (hint: check the status of your CTS line). Let us know what you find. Best, Chuck

18 years, 3 months

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13W3 -> 3 BNC

by mcguire＠neurotica.com

On Sun, May 4, 2008 12:45 am, der Mouse wrote: >> 13W3 -> 3 BNC is common in the world of older Sun workstations, in >> the Sun3 and early Sun4 lines. > > It is? I think all the Sun 13W3<->nBNC adapters I've seen have been > 4BNC or 5BNC, not 3BNC. Ack, you are correct...I've gotten my old Sun monitors mixed up with my old SGI monitors. -Dave -- Dave McGuire Port Charlotte, FL

18 years, 3 months

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Mac Mini inside a Mac Plus

by sellam＠vintagetech.com

http://www.destruc.tv/minitosh.php -- Sellam Ismail Vintage Computer Festival ------------------------------------------------------------------------------ International Man of Intrigue and Danger http://www.vintage.org [ Old computing resources for business || Buy/Sell/Trade Vintage Computers ] [ and academia at www.VintageTech.com || at http://marketplace.vintage.org ]

18 years, 3 months

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13W3 -> 3 BNC

by alexandre.laguejacques＠gmail.com

What a pain... My original DEC 1702906-01 (3W3 -> 3 BNC) cable broke and I needed a replacement. I found one on eBay so I bought two. Instead, the seller sent me a 13W3 to 3 BNC!!! (Where the hell does that thing come from???) I'm trying to contact the seller to work this out. In the meantime, I figured that I'd try here. Would anyone be interested in trading this cable for the one that I really need? FWIW, what I have in my hands cost about 15$ whereas the going price for the 3W3 to 3 BNC (what I need) is around 50$. Thanks! - Alex Alexandre Lag?e-Jacques alexandre.laguejacques at gmail.com

18 years, 3 months

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Low-temp desoldering of SMT

by cclist＠sydex.com

You've probably all heard about Chip-Quik--a low-temp soldering alloy used to desolder SMT at about 150C. Today, I took a scrap board and decided to try my own version. Normally, I keep a fair amount of Wood's metal around for bending thinwall brass tube (filling a tube with the stuff keeps it from collapsing while bending). WM melts at about 158F (70C) and I wondered if the considerably cheaper Wood's metal would do the job that Quik-Chip is sold for. It does--I just removed a TSOP28 package using nothing more than a couple of scraps of WM and a 90W PAR38 spotlight to heat the PCB. I moved the WM around the chip leads a bit and then grabbed the chip with a bit of silicone putty on the end of a fingerip. The chip came right up. A little flux might have speeded things up a bit, but I didn't bother with it. Cleanup was easy--shake the excess metal off the board, wipe down the pads. I'd probably clean the pads a bit more if I wanted to resolder a chip there. Thought folks might like to know. WM is marketed under several trade names, such as Cerrobend. Cheers, Chuck

18 years, 3 months

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Help Needed in Dallas area

by jrkeys＠concentric.net

I will be going up to Dallas sometime after the Memorial Day holidays to pick up a complete Cray YMP (1988 on topic) system and need help loading it all on the truck I will be renting. Is there anyone in the area that could help out with this? Please email me off list and let me know what's a good date(s) for you. I hope to do it over a weekend so that no one would have take off from work. Thanks for looking, John

18 years, 3 months

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RL02K-RF pack

by jim＠g1jbg.co.uk

HI, I found this pack in a pile that I collected yesterday. It is a blue colour (instead of the usual light grey), and has a label detailing expected read voltages and times for inner and outer tracks on each surface. Is it some sort of diagnostic disk? Regards Jim. Please see our website: www.g1jbg.co.uk

18 years, 3 months

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Lookin' for BeBox I/O card or schematics?

by derschjo＠msu.edu

I've had a 66Mhz BeBox motherboard and assorted support hardware sitting in static-proof bags for about two years, all that I'm lacking to get a working BeBox (minus the "Box" portion, since I don't have the chassis) is the I/O board -- without it I have no mouse and I can't get through the installer :). I figure it's a long shot that anyone has a spare I/O board, but does anyone have any schematics for this thing so that I can at least wire up the mouse? Thanks, Josh

18 years, 4 months

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Osborne Vixen drawings

by aek＠bitsavers.org

> I have them scanned, will see about getting them on line. http://bitsavers.org/pdf/osborne/Osborne_Vixen_Engr_Drawings_Mar83.pdf

18 years, 4 months

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blogpost: Tektronix terminals and Apollo DN10000

by legalize＠xmission.com

<http://blogs.xmission.com/legalize/2008/04/30/tektronix-4010-4051-and-4114-…> -- "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/>

18 years, 4 months

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Actually had an RL02 crash today....

by bob＠jfcl.com

. and, although I use RL02s all the time, this is the first time it's happened to me. The odd thing is, the pack was clean and in good shape - in fact, the same pack had been used within the last week without any problems. I knew right away when I spun up the pack that something wasn't quite right - it made an unusual noise when heads loaded. Not a horrible screeching or even the metallic "tinging" sound associated with a crash; more like a soft "swish" noise that I hadn't heard before. It wasn't very loud at all; if I hadn't been right in front of the drive I wouldn't have heard it over all the fans. I spun it down and checked it out - the platter has a really obvious scuff mark ring around the upper surface where the head touched down, and the upper head in the drive had a lot of oxide on it. Surprisingly the lower head also had some oxide on it too, although there are no obvious crash marks on the lower surface of the platter. Fortunately the damage on the upper surface didn't go all the way down to bare metal, and I figured the heads might actually be OK. I cleaned both of them with some Texwipes and alcohol and all the oxide came off, so I found another pack (one that I wouldn't care too much if it crashed too :-), mounted it and gave it a try. The drive appears to be OK despite its adventures, so I'll count myself as lucky this time. The original crashed pack is a write off as far as I'm concerned. Maybe I'll make a clock out of it. I'm really curious though as to what could have gone wrong. The original pack had been used before, and recently too, without any problems and when they're not mounted the packs are stored inside plastic garbage bags to keep dust and dog hair out of 'em. I'm always really fastidious about keeping the drives closed and clean inside, and RL02s usually aren't that fussy anyway. It kind of worries me that despite all the precautions they might decide to up and crash at any time, but I guess that's life with a classic computer. Anybody else have any similar experiences? Bob

18 years, 4 months

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MO disks (was NeXT MO Dump Offer)

by ball.of.john＠gmail.com

>Jerome Fine replies: > >I am in Toronto - M2R 3G3 > >As an estimate, for 50 cartridges, the postage and packaging would >probably be about $ 50 to the US (they are actually quite heavy and >it originally cost about $ 1 per cartridge to ship) making a total >of about $ 100. I would like to recover what I originally paid. > >Of course, the shipping and packaging might be a bit more and the >media a bit less if shipping from Canada to the US poses a problem >for customs evaluation. > >Sincerely yours, > >Jerome Fine Well I live in Kamloops BC (V2C 5G5) so I'm on the other side of the country if that is any help. Mail me at (and include the two periods) ball.of.john<at>gmail<dot>com and we can work out a deal.

18 years, 4 months

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hp 7980 PS board schematic, anyone have one

by aek＠bitsavers.org

> hp 7980 PS board schematic, anyone have one nope. Been looking for 7980/88780 schematics for years now. Schematics were not part of the released service documentation.

18 years, 4 months

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Free items available (UK)

by silvercreekvalley＠yahoo.com

Major clear out means I have several vintage items available, if any interest let me know via email & I can send more info. All items are free but must be collected. Based in Northwest UK 1) Sun Enterprise E4000 with several (probably 8 or 10) CPU's, and around 6G of RAM. CD/DVD drive. All checks out working and in good clean condition. 4 PSUs. 2) Sun 3/60 with 'shoebox' (HD case) and the hard to find SCSI cable. This is a colour system, probably full RAM. 3/60's use a button cell to backup the system settings so its easy to replace - unlike NVRAM chips which can be tricky. Includes a keyboard and mouse (if I can find it). 3) I have a QBUS PDP 11 in an industrial style rack case. This has no front cover but is believed to be functional. More info if required, probably a 11/53 or similar. 4) Last but not least a PDP 11/24 with CPU and RAM (not known how much) and some cabling. A number of unknown cards probably Winchester controllers. In good order but no way of testing. Contact me of list for more info etc if interested.. Ian. ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ

18 years, 4 months

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Osborne Vixen drawings

by aek＠bitsavers.org

> a) are these already scanned and out there somewhere? I have them scanned, will see about getting them on line.

18 years, 4 months

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hp 7980 PS board schematic, anyone have one

by g-wright＠att.net

I have not been able to come up with any source of this. Did HP ever release this information. It is the main Power supply and servo board interface. - jerry Jerry Wright JLC inc g-wright at att.net

18 years, 4 months

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Some old videos - Amiga and AT&T

by silent700＠gmail.com

We've rescued some goofy promotional videos for the Amiga and the AT&T Unix PC from deteriorating VHS format: http://chiclassiccomp.dyndns.org/videos.html Has anyone ever seen an AT&T E4540 terminal? Google has *nothing* on it. Maybe it was never even released? -- silent700.blogspot.com Retrocomputing and collecting in the Chicago area: http://chiclassiccomp.org

18 years, 4 months

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