test-drb

test-drb@ccmp.vtda.org

101090 discussions

inexpensive prototype boards with 22-44 pin edge connector

by lynchaj＠yahoo.com

Sandy's Electronics here in Reno has a bunch $1.00 each, these are the vellman boards and some telecom boards. 20 slot backplanes to match too. www.sandyselectronicparts.com Randy > From: mcguire at neurotica.com <http://www.classiccmp.org/mailman/listinfo/cctalk> > Date: Fri, 4 Jan 2008 10:44:20 -0500 > To: cctech at classiccmp.org <http://www.classiccmp.org/mailman/listinfo/cctalk> > CC: > Subject: Re: inexpensive prototype boards with 22/44 pin edge connector > > On Jan 4, 2008, at 6:51 AM, Roy J. Tellason wrote: > >> Does anyone know where to get some inexpensive prototype boards with > >> the > >> 22/44 pin edge connectors? > >> > >> I am looking for something like DATAK or VELLEMAN boards preferably > >> under > >> $10 a piece. > >> > >> I have looked but have not been able to find any. Any hints would be > >> much > >> appreciated. > > > > I too would be interested in these. They used to be really common, > > and > > could even be found at radio shack for a while, but not these days... > > > > Small prototyping boards in general are of interest to me, with or > > without > > the edge connector for that matter. > > Same here; if anyone finds a good source for decent prototyping > boards, please post it. > > -Dave > > -- > Dave McGuire > Port Charlotte, FL > -----REPLY----- Thanks Randy! Andrew Lynch

18 years, 3 months

S-44 8085 homebrew computer

by lynchaj＠yahoo.com

Hi, Some kind soul took mercy on me and sent me the 2MB ZIP file. If anyone wants it please contact me offline. Thanks! Andrew Lynch > -----Original Message----- > From: Andrew Lynch [mailto:lynchaj at yahoo.com] > Sent: Thursday, January 03, 2008 10:17 PM > To: 'cctalk at classiccmp.org' > Subject: S-44 8085 homebrew computer > > Hi, > > Did anyone get a chance to save the "The Simple Computer II Project" > homebrew computer pages before they went away? > > It used to be here: > > http://www.interparse.com/microcomputer/simpleii.html > > for some reason it has disappeared. > > I tried the internet archive and it found a copy but it is missing > graphics. > > http://web.archive.org/web/20070702182520/http://www.interparse.com/microc > omputer/simpleii.html > > If anyone has a copy, please send me one or post a link. > > Thanks! > > Andrew Lynch

18 years, 3 months

Is there a Catweasel like device for hard disks?

by cclist＠sydex.com

> Date: Thu, 3 Jan 2008 21:07:02 +0000 (GMT) > From: ard at p850ug1.demon.co.uk (Tony Duell) > If by 'commodity solutions' you mean the WD1010 or whatever, then I have > to disagree with you. Plenty of manufactuers used their own ASICs in the > hard idsk controller, and admittedly most of them did do a fairly normal > MFM or RLL2,7 encoidng. But I'll bet at least one didn't! The latter is what I said--and meant. "Unique" encoding schemes, such as one finds on floppies (zoned recording, CLV, various flavors of GCR, FM, whatever you want to call the Apple II flavor of GCR, "mixed" formats, such as the RX02, etc.) were comparitively rare. MFM and RLL 2,7 were overwhelmingly the rule on the ST506 and ST412 class drives. I mentioned the Perstor with ARLL, but it was hardly the rule. > And I've got machiens that use a 8x305 in the hard disk controller. And there are plenty of systems that use the 8x30x and the WD1000 series chipsets (the WD1001 being one of the boards). Still MFM. > A kludgeoard was added (and the CPU microcode device diivers changed) > to talk to a Micropolis 1203, and finally a different kludgeboard and > CPU microcode were used to talk to ST412 drives. I would not want to > bet that the encoding on that was normal, at least not without doing a > lot of tests. I'd be willing to wager that it was MFM or M2FM of some flavor, however. I've got an SA4000 and controller that's implemented in TTL with nothing more complex than a few 74LS181s and a few ROMs. It's still MFM recording. My point was that with a decent data separator for the common modulation methods and a simple deserializer, you'd have all you'd need to cover the overwhelming majority of ST412-type drives. No need for fancy transition-time recording as in the Catweasel (where one often can spend a great amount time staring at a histogram and pulse-time list trying to figure out how clever the designers of a particular floppy format were.) Cheers, Chuck

18 years, 3 months

Is there a Catweasel like device for hard disks?

by cclist＠sydex.com

> Date: Thu, 03 Jan 2008 12:31:03 -0500 > From: "Roy J. Tellason" <rtellason at verizon.net> > I ran a perstor card with a pair of ST251 drives up until I got my first > 540M ATA drive, 24/7, for a few years, and they proved quite reliable. > The bearing noise of those drives got to be a bit much by the time I shut > them down, though. Was this the ARLL (2x MFM capacity) Perstor controller? If that's the case, I'm doubly surprised. On the first count that you got ST251s to perform reliably with it and, on the second count, that you didn't have to use ST251R drives. I seem to recall that the difference between the ST251 and the ST251R was how individual specimens behaved on final QA. They both started off as the same drive, but some performed better than others and so were labeled with the "R" designation. I don't know if it was the bearing noise of the 251s that was more objectionable or the resonance from the copper spring clip at the end of the spindle. On some drives, the spindle brake would fail leading to some really awful squealing noises from the brake pad. My usual solution was to remove the culprit, whichever it was. Cheers, Chuck

18 years, 3 months

Is there a Catweasel like device for hard disks?

by cclist＠sydex.com

Date: Thu, 3 Jan 2008 18:59:10 -0800 (PST) From: Fred Cisin <cisin at xenosoft.com> > It may depend on how we define "reliably". > > Remember when Steve Gibson's Spinrite (not the current edition, now) > would, by default return to use tracks that were on the manufacturer's bad > track list, if they passed Spinrite's "tests". He wasn't the only one to try that nonsense. I recall a fellow proudly proclaiming that he didn't bother with the flaw map printed on each drive as "most of those flaws are fake anyway". Cheers, Chuck

18 years, 3 months

Testing a 1488 line driver...

by cclist＠sydex.com

If it hasn't been mentioned yet, I'd start by unsoldering the DC-DC converter that supplies -12 and temporarily replace it with a 9v battery to see if the converter was at fault. Check for a dead short before you hook the battery in... FWIW, I've blown 1488/89s by dragging my feet across a carpet to generate sufficient potential to cause a small arc when I plugged in the comms cable (the far end wasn't yet connected). Cheers, Chuck

18 years, 3 months

wrt recent DEC talk

by chrism3667＠yahoo.com

someone posted something about DEC racks. I'm not exactly sure what a rack is in this context - didn't read the posts nor do I intend to, but I have a DEC cabinet thing that's presently sitting out in the yard. If this is what was meant by a *rack*, a cabinet/battleship on casters type things, then there's one sitting out in the yard. In good shape I would think. If anyone's interested, give me a hollur. O and MERRY CHRISTMAS and HAPPY NEW YEARS all you psyk vintij gewrooze you! LOL LOL! ____________________________________________________________________________________ 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

S-44 8085 homebrew computer

by lynchaj＠yahoo.com

Hi, Did anyone get a chance to save the "The Simple Computer II Project" homebrew computer pages before they went away? It used to be here: http://www.interparse.com/microcomputer/simpleii.html for some reason it has disappeared. I tried the internet archive and it found a copy but it is missing graphics. http://web.archive.org/web/20070702182520/http://www.interparse.com/microcom puter/simpleii.html If anyone has a copy, please send me one or post a link. Thanks! Andrew Lynch

18 years, 3 months

Is there a Catweasel like device for hard disks?

by cclist＠sydex.com

> From: Jules Richardson <jules.richardson99 at gmail.com> > Hmm, I thought I read once that you could throw pretty much anything you > wanted at a ST506 drive so long as it was within the various tolerances - > is that not true of ST412-type drives? While that may be true in theory, I'm going to guesstimate that 99 and 44/100 percent of the applications of the ST506/412 out there used either MFM, MMFM (maybe) or 2,7 RLL for recording. While anyone could throw together a bunch of TTL chips to record any old way on a floppy (and did), implementing a hard disk controller with random logic wasn't a simple matter and almost all manufacturers, by the time of the ST506 used commodity solutions. That's not to say that there aren't any bizarre recording schemes out there for ST506s; just that I've never run into one. For example, I've got a few mutually incompatible 2,7 RLL PC-AT style controllers, but they differ more in logical details (address marks, header layout, ECC codes) than they do in modulation methods or clock rate. While it may have been possible to, say, employ FM recording on a ST412, I've never seen it done in practice. There *were* some RLL variants that attempted to push things past 2,7 (Perstor?) on a 412 interface, but they were never very reliable or popular. Did any application of a 506 even use zoned recording (i.e. using a faster data clock on the outer cylinders)? Cheers, Chuck

18 years, 3 months

Mailing list search

by djg＠pdp8.net

I have never gotten it to work. I have tried a couple times over some reasonable long (month?) time and it always says no matches found. Is it just me? http://www.classiccmp.org/pipermail/cctalk/ No matches were found for '(digital or digitally)'

18 years, 3 months

10 MHz to 5 MHZ conversion

by ron＠raspet.com

Dear Bruce, I have a Cushman 6-A service monitor. The 5 MHZ crystal oven assembly has died. Do you have a source for the 10 MHZ crystal and how did you provide both the TTL and sine 5 MHZ for the Cushman instrument. I am retired and I would like to keep the 6-A working without spending a lot f dollars. Thanks for your help!! Ron Raspet N3JLF No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.17.13/1208 - Release Date: 1/3/2008 3:52 PM

18 years, 3 months

reality check (was: offer - OS/2 for the PDP-11)

by aek＠bitsavers.org

ggs said: > Folks, there was *no* OS/2 for anything other than the x86 and the PPC. Awww, injecting REALITY into typical classiccmp nonsense. Also, there was NO NT for the 68K, as it REQUIRES little-endian support in the CPU.

18 years, 3 months

Is there a Catweasel like device for hard disks?

by cclist＠sydex.com

> Date: Wed, 02 Jan 2008 14:28:23 -0600 > From: Jules Richardson <jules.richardson99 at gmail.com> > Andrew Lynch wrote: > > Hi, > > Just out of curiosity, is there a technique or device which can do raw > > reads of tracks on ST506/ST412 style hard disk drives similar to how a > > Catweasel can with a floppy disk drive? > > To the best of my knowledge, no - and I've been keeping an ear to the > ground for such things for a while (plus it's a discussion which crops up > here every once in a while, but I don't believe anyone's produced any > working hardware yet). > > The speeds involved (particularly if over-sampling the data) are > reasonably high - enough that it'd be tricky[1] to throw something > together out of OTS TTL parts. That puts such a project more within the > realm of people who know all about interfacing to high speed > microcontrollers, and the pool of available carbon units with the time, > skills and inclination to make such a device is pretty darn small. I'll assume that we're talking about (surviving--and that's a real gotcha) ST506/ST412 interface drives here. Why would a Catweasel- type interface (i.e. pulse time sampling) be even desirable? All the drives used to store digital data that I'm aware of were recorded as MFM, M2FM or some flavor of RLL (2,7 probably being the most common). Controllers differ in small details such as address marks which renders them mutually incompatible, but the data stream has far less variation in encoding than the floppy world. Just give me a programmable data separator and a way to capture that output--I'll figure out what the bits mean. The rated speeds of old ST412-type drives were pretty modest; about 5MHz for MFM and 7.5MHz for RLL, IIRC. Cheers, Chuck

18 years, 3 months

PC100 update (VT-100 emulator)

by dave06a＠dunfield.com

Hi Guys, I've just posted an updated PC100 to my site - excepting for bug fixes (please send reports), this should be the last version for a while, as it has reached the point where it does everything I need (and more). Updates in this version: - Implemented slow-scroll as a substitute for smooth-scroll - Improved key mapping function so you can more easily see the existing mappings. - Added a BREAK key (finally) - and programmable break timing. (Removed the BREAK function from the menu) - Programmable ^G and Margin BELL fequency and bell length. - Programmable VT-100 DA response value (mainly so that you. can decide if the terminal indicates AVO present or not). PC100 is a PC based VT-100 emulator which: Runs under DOS, so you can use any old PC as a VT-100 Is more complete than any other DOS VT-100 emulator I've seen, supports everything from the DEC VT-100 documentation (including VT-52 functions) except for: - Double Wide/High characters. - Smooth scroll is implemented as "slow scroll". Supports all VT-100 attributes correctly (VGA). Supports full VT-100 graphics character set (VGA). Keyboard is fully mappable, including Shift, Control, NoScroll, Break, and all other VT-100 key functions. You can use ANY key on the PC keyboard for any VT-100 key. Default layout replicates the DEC keypad to the extent allowed by the physical differences. Additional (non-VT-100 features): Powerful script language lets you automate sessions. File transfers - ASCII is built in, and can link to external programs for other protocols. I include a XMODEM/YMODEM module. 30 programmable function keys with status line labels and up to 64 character transmit strings (I use them for commonly issued commands during debug sessions). Enjoy, Dave -- dave06a (at) Dave Dunfield dunfield (dot) Firmware development services & tools: www.dunfield.com com Collector of vintage computing equipment: http://www.classiccmp.org/dunfield/index.html

18 years, 3 months

Looking for some 74s124's

by jos.mar＠bluewin.ch

For some modifications on a classic computer I need 1, preferably 3 74s124 ( TTL VCO's) Cannot seem to locate them locally (Zurich, switzerland ) and would rather not pay the 30 UKP each quoted for them by some UK based shop... Anyone with a well stocked spare parts store ? (I tought I had one, but no '124 among the several 1000 IC's I stocked ) Jos Dreesen

18 years, 3 months

offer - OS/2 for the PDP-11

by compoobah＠valleyimplants.com

On Jan 2, 2008, at 6:31 PM, Zane wrote: > I believe the first version or two of Windows NT shipped with x86, > Alpha, > PPC, and MIPS hardware support (at least I think those were the 4 > listed > architectures). Somewhere I should have a box that says it supports > all 4. NT4.0 definitely does - I put it on an AlphaServer once for the novelty (booted it up, said "why bother?" and installed something more DIGITesque and appropriate).

18 years, 3 months

offer - OS/2 for the PDP-11

by cclist＠sydex.com

Somebody wrote (sorry--I lost the original digest:) > Many will disagree with me, but I feel that a floppy based OS that can't > handle non-contiguous files is the worst product ever marked as being an > OS. They're more common than you'd think, particularly in OS for industrial machinery, such as CAD equipment and embroidery machines. Typically, the diskette is written only once for a particular job (usually as a paper tape substitute) and read over and over again. In those cases, it makes perfect sense. Non-contiguous floppy files can be a real drag on the older floppy- based systems that used drives with very slow positioners (now, why does "Micropolis" immediately come to mind?). A scheme that involves contiguous allocation with a fixed number of shots at extending (in case you mis-estimated the size) works well on slow floppy systems. For many single-user applications, it's possible to employ an "allocate the remainder of the disk and truncate on close" scheme. It's also a piece of soup/duck cake to recover files from a floppy using contiguous allocation where the directory and allocation information has been destroyed. (Even better to incorporate recovery information throughout the diskette instead of one track that gets hit over and over again, but that's another story). (Have you ever had to recover a "work" floppy full of Lotus 1-2-3 spreadsheet data without a directory or FAT?) More related to the topic is that DEC VMS FILES11 had an incredibly complicated floppy file system. Maybe BTOS was worse... Cheers, Chuck

18 years, 3 months

Free terminals in Nashua, NH

by kyrrin＠bluefeathertech.com

The fellow who sent me the attached message has a fully functional VT50 and VT52 terminal available. Please contact him directly if interested. Thanks. *********** BEGIN FORWARDED MESSAGE *********** On 31-Dec-07 at 12:33 Robert D. Houk <rdh10 at comcast.net> wrote: > From an old URL I had stashed away some years ago: > > > If you, your company, or your employer is getting ready to dispose > > of old hardware, and before you decide to send ANY such equipment to > > the landfill, please drop me an E-mail and let me know what you have > > and where you are! This holds especially true for military surplus > > radio and electronic equipment or test gear. > >Is this still "active"? > >Are you interested in (to start with) a DEC VT50 and VT52 (both fully >functional the last time I used them) CRT terminals ("glass TTY")? >Free to anyone who wants to come by and pick them up . . . (Nashua, >NH) > >Just wondering (more to the point, cleaning up lots of old email, >URLs, and other notes I've left myself over the ages). > >-RDH *********** END FORWARDED MESSAGE *********** -=-=-=-=-=-=-=-=-=-=-=- 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, 3 months

Is there a Catweasel like device for hard disks?

by lynchaj＠yahoo.com

Hi, Just out of curiosity, is there a technique or device which can do raw reads of tracks on ST506/ST412 style hard disk drives similar to how a Catweasel can with a floppy disk drive? Thanks! Andrew Lynch

18 years, 3 months

wanted "PC Brand" system and "Best Data" 2400 Modem

by mikelee＠tdh.com

This is pretty boring and only borderline "classic", but for sentimental reasons, I'm looking for a beige box-ish "PC Brand" computer. Anyone happen to know of, or anything about them or the company? Figured by some chance, somewhere here knows something and may even have one stashed away still. They were sold mail order early 1990. The ones I know of were a desktop style, 386 or 486. The system itself was not a standard common AT, but a "PC Brand" laid out chassis and motherboard as far as I can tell. Also, looking for an Internal ISA "Best Data" 2400 modem. A generic POS, but still I'd like to just get my hands on one.

18 years, 3 months

Mail formatting

by tiggerlasv＠aim.com

Something is definitely amiss. . . Take a peek at Henk's last posting, dated Sat Dec 29 05:08:15 CST 2007 The first line is quoted text in response to one of my postings. It looks like the carriage returns were stripped out somehow. Still other postings (where Ethan reported problems) looked fine when I read them.?? There might be TWO different symptoms being displayed. Of course, I noticed that in at least one of my postings, there are some extraneous characters that came across, that weren't in the body of my text. This might be due to the way A-oh-well (AOL) formats their e-mails. Tim ________________________________________________________________________ More new features than ever. Check out the new AIM(R) Mail ! - http://webmail.aim.com

18 years, 3 months

Vector and ST506 (was: ST506 and-or ST412 hard drives.htm

by cclist＠sydex.com

> Date: Mon, 31 Dec 2007 18:07:38 -0500 > From: "Andrew Lynch" <lynchaj at yahoo.com> > The different signal is called a "constant index" signal. Apparently, it > is similar to an /INDEX signal from a floppy drive interface but the > signal tells the HD controller everytime sector 0 passes around. The HD > controller requires it for setting up the PLL. > > Here is an excerpt on the subject from the VG engineer: Well, the ST506 knows nothing from sectors--it's about as "bare" and interface as they come. I wonder if by "constant index" it's meant that there's always an INDEX/ signal present; not just when the drive is selected. At least that would make sense from this: > All hard drives working with a Vector FD/HD must have constant > index. There is a phase locked loop that is controlled by U20 which > is CMOS 4040 chip and unless you have constant index the PLL never... Maybe? What happens if the drive is jumpereed so as to be permanently selected? Cheers, Chuck

18 years, 3 months

Vector Graphic computers

by lynch610＠sbcglobal.net

Hi If anyone has any Vector Graphic computers they would like to restore I would like to offer some help if they would like it. Vector Graphic computers can be challenging to restore because of the unusual hardware requirements (100tpi floppy disk drives, 16 sector floppy disks, etc) and a relative scarcity of applicable software and/or boot disks available on the internet. The friendly people on the Vector Graphic mailing list have made a lot of progress lately on various VG projects like the VG simulator, disk imaging project, a disk image library, ROM image library, more comprehensive documentation, etc. Even some hardware related issues like make and burn ROM images, how to boot your VG using 96tpi floppy disk drives, how to make or buy your own 16 sector floppy disks, etc. Check out http://vector-archive.org for some of the new resources available. Thanks! Andrew Lynch

18 years, 3 months

Wanted: ultra-rare Commodore 64 stuff

by dgahling＠hotmail.com

Yeah, I've tried the commodore forums, for sale, craigslist, etc. no luck I thought I'd try my luck here, no harm I think. I'm looking for something very rare on the commodore 64 (c64 or 64c) line of computers, it was called "drive mirror" for the 1541 disk drives it was basically an LCD display built into the drive that showed the track and sector values. it also had a half-track indicator and a "density" indicator as well. I read a magazine article (or online) once that showed how to do the track and sector displays, but never had any info about the more interesting parts - the half-track and the density display. if anyone has one or knows how they worked, or how to make one, please let me know. I'm also looking for a software copy of "Trackmimic" it was part of a hardware copier for the systems. I can make the cables myself (learned how a long time ago), but lost the software somehow. I'm also looking for a software program called "Di-Sector" specifically version 4 of that program. there are a LOT of fakes out there that claim to be version 4, but they're all spyware or trojans. which is sad. I've seen the "real" thing back in the day, so I know it's out there, or was. Any of this, for sale, trade, or just to give to a good home, or to put my out of my misery would help! greatly appreciated Dan. _________________________________________________________________ Discover new ways to stay in touch with Windows Live! Visit the City @ Live today! http://getyourliveid.ca/?icid=LIVEIDENCA006

18 years, 3 months

IBM 3380 and 3880 manuals

by smith-rj＠comcast.net

Just Wondering.. Did you ever find the 3380 maintenance manuals. I wrote the installation section of the manuals, and I don't have a personal copy. Any help? Ray Smith

18 years, 3 months

Jump to page:

2026

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

2001

2000

1999

1998

1997

test-drb