test-drb December 2005

test-drb@ccmp.vtda.org

235 participants
580 discussions

trying to design my first micro- looking for "prior art" (6100 and6809)

by bobwyates＠earthlink.net

Might be some ideals here. Excuse me if this has already been mentioned, not following the list too closely. http://homepage.mac.com/dgcx/pdp8x/

18 years, 11 months

OS/9 and software for the 6809 (was RE: trying to designmyfirstmicro- looking for "prior art")

by ajp166＠bellatlantic.net

> >Subject: RE: OS/9 and software for the 6809 (was RE: trying to designmyfirstmicro- looking for "prior art") > From: "Robert Armstrong" <bob at jfcl.com> > Date: Sat, 03 Dec 2005 13:05:42 -0800 > To: "'General Discussion: On-Topic and Off-Topic Posts'" <cctalk at classiccmp.org> > > > Actually, I'd rather do a Z80-CP/M machine, but the same problem applies >(need a software person to port CP/M). > >Bob That I can do in my sleep. The only caveat would be if it had a device not laying around as yet.. Always an excuse to play with new devices. I've done it enough times and re did some ports as well. The real question I would ask is CP/M2 or one of the later ones off the P2DOS tree (z80 compatable cp/m clones) that offer larger disks (greater than 8mb logical drives)? It's a BIOS, system specific docs and setting up a standard package task. Allison

18 years, 11 months

EPROM Substitution

by henk.gooijen＠oce.com

I vaguely remember that all 2532 and 2732 EPROMs were compatible *except* the TI one. (or was it an other manufacturer?) >From that one manufacturer the 2532 used a *second* power supply ... was it -5V? Memory is dropping bits :-( Check the board before you install a 2732 ! It's of course OK to put in an other TI 2532 (same as the original one). - Henk, PA8PDP. ________________________________ Van: cctalk-bounces at classiccmp.org namens Bruce Lane Verzonden: za 03-12-2005 06:17 Aan: cctech at classiccmp.org Onderwerp: EPROM Substitution Fellow techies, I've got a nice item of Z80-based, 1986-vintage, telephone test gear that I'm trying to restore to working condition. The CPU board, as it currently stands, uses a pair of TI 2532 EPROM chips for program memory. I suspect both chips have become borderline in terms of their timing tolerances, so I need to replace these with the more readily available 2732, of which I have plenty. The pinout between the two chips is slightly different, thanks to the fact that the 2532 has only one enable line and the 2732 has two. I've come up with an idea for conversion, but I'd really like to get a sanity check on it, preferably from someone with an original TI data book that covers the 2532. Here's what I've got so far, based on comparing the pinouts of the two devices. (1) Move the trace originally connected to pin 18 (A11) on the 2532 up to pin 21, which appears to be A11 on the 2732. (2) Tie pin 18 to pin 20 so that, on the replacement 2732, both /CE and /OE are asserted simultaneously. Did I miss anything? Thanks much. -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner & Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m "If Salvador Dali had owned a computer, would it have been equipped with surreal ports?" This message and attachment(s) are intended solely for the use of the addressee and may contain information that is privileged, confidential or otherwise exempt from disclosure under applicable law. If you are not the intended recipient or agent thereof responsible for delivering this message to the intended recipient, you are hereby notified that any dissemination, distribution, or copying of this communication is strictly prohibited. If you have received this communication in error, please notify the sender immediately by telephone and with a "reply" message. Thank you for your cooperation.

18 years, 11 months

More parts I need to replace on the VT100

by dwight.elvey＠amd.com

>From: ard at p850ug1.demon.co.uk ---snip--- > >However, they seem to be a lot less use when it's a one-off unit which >you need to repair no matter what (like a classic computer). You're going >to have to do real fault diagnosis sometimes anyway, it doesn't make it >much more difficult to do it properly every time. > Hi Once many years ago while working for Intel, I was called in to help fix a number of what we used to call yellow dot boards ( failed but not repaired after third rework and had a yellow dot placed on them ). The yellow dot inventory had a sudden jump so someone needed some additional help. The boards had a lot of analog circuits on them because they had a discrete component PLL used for the disk controller. I had the fellow from system test with me to take notes on how to diagnose complicated failures on these boards. As it turned out, about 90% were caused by a mix up in the parts loaded on the boards. A low voltage zener was placed in a number of locations that expected signal diodes. This especially effected the balanced mixer used in the phase detector. After some time of carefully showing the system test fellow a number of scope signals and carefully explaining the reasons I was looking at particular locations, I happened to glance at his notes. It went something like this: D3, D5, D8, D20, D21 There were no symptoms and nothing of what I showed him about scope information. I soon realized that he was just interested in a list of parts that I indicated as causing problems and wasn't even paying attention to anything else I was doing. The worst part was that since this was a one time parts mix up, it probably would never happen again so that his list was virtually worthless. I told him this but that didn't seem to ring a bell with him. Dwight

18 years, 11 months

EPROM Substitution

by kyrrin＠bluefeathertech.com

Fellow techies, I've got a nice item of Z80-based, 1986-vintage, telephone test gear that I'm trying to restore to working condition. The CPU board, as it currently stands, uses a pair of TI 2532 EPROM chips for program memory. I suspect both chips have become borderline in terms of their timing tolerances, so I need to replace these with the more readily available 2732, of which I have plenty. The pinout between the two chips is slightly different, thanks to the fact that the 2532 has only one enable line and the 2732 has two. I've come up with an idea for conversion, but I'd really like to get a sanity check on it, preferably from someone with an original TI data book that covers the 2532. Here's what I've got so far, based on comparing the pinouts of the two devices. (1) Move the trace originally connected to pin 18 (A11) on the 2532 up to pin 21, which appears to be A11 on the 2732. (2) Tie pin 18 to pin 20 so that, on the replacement 2732, both /CE and /OE are asserted simultaneously. Did I miss anything? Thanks much. -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner & Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m "If Salvador Dali had owned a computer, would it have been equipped with surreal ports?"

18 years, 11 months

OS/9 and software for the 6809 (was RE: trying to design my firstmicro- looking for "prior art")

by ajp166＠bellatlantic.net

> >Subject: OS/9 and software for the 6809 (was RE: trying to design my firstmicro- looking for "prior art") > From: "Robert Armstrong" <bob at jfcl.com> > Date: Sat, 03 Dec 2005 10:12:31 -0800 > To: "'General Discussion: On-Topic and Off-Topic Posts'" <cctalk at classiccmp.org> > >>compoobah at valleyimplants.com wrote: > >> Sounds like I'm back with 6809 as being easier to work with. >> I'll sit down with what I've got here and see what I can come >> up with (I'm more interested in designing than just having a >> "soldering skills test"). > > I love fooling around with old microprocessors too, but one of my issues >is that I hate writing software for them. After I get all the hardware >built, I'm kind of stuck with the question "Now what???" Toggling in little >LED blinking programs and things like that gets old pretty fast. That's one >reason I picked the 6120 - OS/8 and related stuff is readily available on >the Internet - and the Elf - there's lots of original Elf software around, >plus Mike Riley did a great job writing a real disk OS for it. > > I know there was at one time an OS/9 for the 6809 - does anybody know the >status of that today? Is there other software for the 6809 floating around >these days? > > Of course, you may not share my hangups about writing software ... > >Bob look at http://www.parse.com/~ddunfield/museum/index.html Scan down to homebrew and 6809. Dave did both a simple 6809 and a full up OS and supporting tools including a simulator so you can drive it now. the think I liked most is the kernel is 8k and the sources are there as well as decent docs. OS9 seems to be tied to existing hardware like coco and I'm not sure sources are out there as free. Allison

18 years, 11 months

Mac Mini

by zmerch＠30below.com

Rumor has it that Ethan Dicks may have mentioned these words: >On 12/3/05, Tony Duell <ard at p850ug1.demon.co.uk> wrote: > > [1] Does a USB-GPIB interface exist? I assume it must do, but I've not > > seen one (I've not seriously looked either, my GPIB stuff is generally > > controller by HP hosts [2]) > >I think I've seen one - not cheap, but neither are PCI GPIB cards - if >you need one, you *need* one and will pay. I've seen one in captivity! Saw one at a car dealership - they deal with both GM & Chrysler products, I *think* it was used on the Chrysler end o'things... Since then I found a website that had 'em for sale... I think around $220 to $250 USD each, but they had 'em. Google is your friend here... ;-) Laterz, Roger "Merch" Merchberger -- Roger "Merch" Merchberger -- SysAdmin, Iceberg Computers _??_ zmerch at 30below.com (?||?) If at first you don't succeed, nuclear warhead _)(_ disarmament should *not* be your first career choice.

18 years, 11 months

SCSI Controller, 1530 Datassette, Ebay seller, etc

by mokuba＠gmail.com

Ebay user ID nnn0iab has interesting stuff going up - HVD scsi controller, and such, I just noticed him while browsing commodore stuff on ebay, figure if he's got this sort of thing going up there might be more. Do any of you people watch specific sellers like this just to see if something interesting comes up? OH! And he's the seller of a 'christmas card holder' you might be interested in... http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5642635569 - I wonder if that christmas card holder will sell for anythign higher then a few dollars... <Watches everyone put a pentium 2 on ebay as a card holder and the value of pentium 2s plumet even more> Are there any other interesting sellers you could point out to me?

18 years, 11 months

Old MS-DOS & WIN Software

by dm561＠torfree.net

I just happen to have a sealed NIB ObjectVision 2.1 on a shelf beside me, although it may be spoken for (and you might have trouble getting the $10 rebate :); as to the rest, no idea at this time but not likely. It'll take me a while to dig through this stuff, so please send me a note off- list and I'll let you know when I have a list of what there is, condition, and what it's worth, if anything. TIA, mike (in Toronto) ------------------Original Message-------------- Date: Fri, 02 Dec 2005 19:09:16 -0700 From: micheladam at theedge.ca Subject: Re: Old MS-DOS & WIN Software Hi. Would you happen to have Turbopower Software stuff? Like ObjectProfesionnal? Also, Microsoft TCP/IP SDK for DOS ? Borland ObjectVision 2.1 ? Faircom CTREE ? Thanks Michel Adam ----- Original Message ----- From: M H Stein <dm561 at torfree.net> Date: Friday, December 2, 2005 2:07 am Subject: Old MS-DOS & WIN Software > I'm getting rid of several large boxes of old MS-DOS & WIN > software, OSs, apps, languages, utilities, games, etc. > > Also boxes of hardware such as PC MoBos, cards, keyboards, > external print buffers, converters, <=9600bd modems etc. <snippage>

18 years, 11 months

6502 nixie project

by ryan＠hack.net

This has been occupying my time lately: http://www.hack.net/nixie It's my homebrew 6502-powered Nixie clock. Designed it from scratch; thought the other "classic computer" people here might enjoy the write up. -Ryan Brooks ryan at hack.net

18 years, 11 months

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test-drb December 2005