test-drb

test-drb@ccmp.vtda.org

101090 discussions

by dave13＠dunfield.com

WOW - a lot of response in just 1/2 day! Just a few notes to clear up a few things: I am NOT "giving away" the collection - I will no doubt give away some parts of it, but I know local (to me) collectors who will take those bits, so please only ask for freebies if you are very close to Ottawa, Ontario. It also doesn't do much good to ask me "how much do you want for xxx" as I really don't know, as I have never made a point of placing values on the items in the collection - better to let me know what it is worth to you. Ultimately any particular item will go to whomever places the highest offer, or in some cases places where I know the particular bit of equipment will do the most good or have beneficial effect. At present I am planning to keep at least one of the Altairs, the Imsai, the Vector, the Horizon, the H8. one of the "chicklet" Pet 2001s the VLC VAX, the D6809 (or course) and a probably couple of others I have not decided on ***. *** I'll willing to entertain offers on these systems, but don't expect them to be cheap - I'm just as happy to hang on to them. I'm not keen to ship - I know this lets out many (most) of you, but preference will definately be given to people who can arrange pickup or take care of most of the shipping hassles remotely. In particular, I can't easily tell you what shipping will cost - most of this stuff is heavy, and it is a lot of work to pack something, measure it, weigh it and get a quote - which will likely be too high (as you all know, much of this stuff isn't worth the cost to ship). I'm happy to work with you to figure out ways to get things to you - perhaps piggybacking transport on someone already planning to come here etc.. (You might be able to coordinate such things through the list as well). Thanks, Dave -- dave13 (at) Dave Dunfield dunfield System/Firmware development services: www.dunfield.com (dot) com Classic computers: http://www.classiccmp.org/dunfield

12 years, 11 months

RSX-11Mplus boot SAV -- Cannot find Home Block on fpga pdp2011

by cclist＠sytse.net

I've long thought that my pdp2011 would run just about anything pdp11. However, it was recently brought to my attention that RSX-11Mplus will not boot from an rp06 disk image. I mean, an rp06 image created on simh, based on the rd54 image in rsx11mpbl87.dsk.bz2, sysgenned to support rp06 drives, and working without any problem on simh. The first steps in the boot on the fpga appear to work fine - several reads are done, and the first message appears: "RSX-11M-PLUS V4.6 BL87 1024.KW System:"RSXMPL". So far exactly the same as when I run simh on the same image. However, after a brief pause in which the cpu is busy, a difference appears: simh will continue with a few reads and finish the boot process; however, my fpga will start reading sectors from each cylinder of the disk in ascending order - ie, beginning at cyl 0 and ending at the last one. When at the last cylinder, the message "SAV -- Cannot find Home Block" appears. Strangely, if I google that, it comes up with a reference to Ersatz-11 from 1994 which appears to describe exactly the same behaviour - only then on RL, apparently. See ftp://minnie.tuhs.org/pub/PDP-11/Sims/Ersatz-1.1beta/Old/e11beta.txt I've spent most of my free time last week chewing on this problem, looking at many details in my controller vhdl. However, I've not come any closer to a solution. At this point, I'm not even completely sure that the problem actually is in the controller - since E11 had the same thing in it's RL, and that is a completely different thing. So, I'm hoping that someone on this list can help me understand what the trigger(s) for the "SAV -- Cannot find Home Block" could be. Is there maybe someone who remembers the original issue in E11, and how it was fixed? Or is there someone with access to the source code who could explain what happens?

12 years, 11 months

uVAX 3900 out to lunch after inactivity

by fraveydank＠gmail.com

The long saga of making my recent KA655 acquisition work continues! It's been mostly smooth sailing since I got a decent Plextor drive, but there's one persistent problem. Under VMS 7.3, after a longish period of inactivity (I've seen it after a few hours, but I've not been able to narrow it down beyond that), it seems to just kind of go out to lunch. VMS is still *running*... if I have a Telnet session running MONITOR, the clock will still update and the activity meters still move (a little; they show very little activity, but that's expected since there's not a lot going on on the machine yet). But if I terminate MONITOR (it responds interactively to ctrl-C, etc) and try to run anything else (say, HELP), it stops responding. Other terminals are totally unresponsive. If I try to open a Telnet session, TCP connects but no other traffic happens. This also happens if I turn TCP/IP off. I'm running with 16 MB RAM, which should be enough for a machine that's not really running much yet, and if I were having memory issues I would expect things like existing MONITOR sessions to have serious problems. The only other correlation I can think of is that this seems to happen most when I've just installed a layered product, so it could have something to do with the CD still being mounted. On the other hand, I tend to leave the machine alone and unattended for long periods of time for product installs, so correlation is necessarily not very trustworthy here. I can still issue a break from the terminal and boot again >from the console firmware, so that still seems fine. If anyone has any idea what might be going on here, I'm all ears. - Dave

12 years, 11 months

Airplane cockpit instruments, DEC PDP peripherals and other old computers on ebay, near Munich

by joerg.sigle＠jsigle.com

Hey guys. Here are some DEC drives, among other things. Obviously someone who selected interesting hardware and stored it rather carefully. I was considering the Apollo or even the Technostar, but it would be an effort for me just to get there. If anybody is closer or very interested, tell me, so I may not bid. The seller (acting on behalf of owner) wrote he gave the PDPs "in good hands :-)" (his own?), but his prices are not so low, and he says he is considering 350 EUR for 8 apollos with only one Monitor, two keyboads, mice, unknown condition, long storage... Just wanted to point you to the auctions, just in case. ebay auctions: 251267118551 251270611957 251268195362 251270185222 PDP RL02, some RL06 and 07 have apparently already ended. etc. pp. (Please look for other auctions of this seller, included completed ones.) I think it would definitely be very sad to let these machines go to scrap - would anybody second that? :-) Kind regards, Joerg

12 years, 11 months

Downsizing - many systems available

by dave13＠dunfield.com

>> The collection can be seen at: www.classiccmp.org/dunfield >> >> [Keep trying if it says "service unavailable" - the classiccmp >> server seems to be having problems lately] >> >Most of the picture links appear broken. :( The links are not broken. The classiccmp server is broken. The photos don't work because you browser cannot access them - try enough times and you will usually see them (or go nuts trying). It's not just my site - the entire classiccmp server is having problems and has been for quite some time. Most of you don't see it because you access cctalk/tech via email, which gets done "in good old time", however I am not actively subscribed to the list any more (too mucn traffic), so I read the list via the web archives - depending on the time of day and phase of the moon, this can be damn near impossible. Many days I just give up. Makes the site pretty useless I agree - If anyone can provide a better host for the site I'm very interested, but for now I just don't have another place to put that much material - the alternative is probably going to be just taking it down as it really hasn't worked properly in weeks. Dave -- dave13 (at) Dave Dunfield dunfield System/Firmware development services: www.dunfield.com (dot) com Classic computers: http://www.classiccmp.org/dunfield

12 years, 11 months

ios IBM 5170 hard disk with 47 user

by enrico.lazzerini＠email.it

I'm trying to install a hard drive IBM H3256-A3 (manual here <http://www.hgst.com/tech/techlib.nsf/techdocs/7BF937434F9F7BBC86256E9000734 60D/$file/oem3fspe.pdf> http://www.hgst.com/tech/techlib.nsf...e/oem3fspe.pdf ) in an IBM AT 286. I state that the motherboard 286 type 1 with a controller AB-862G SUPER MULTI I/O CARD and a pair of drive performs the correct boot of the dos 4.0 (with no hard disk connected and configured), and that the alone hard drive works and has been perfectly formatted in dos way on another P3 machine. I replaced the original U27 and U47 with the bios BIOS_5170_30APR89_AMI_D286-1277-043089-K0 (downloaded the AMI BIOS FOR 5170 at the bottom of this page <http://www.minuszerodegrees.net/bios/bios.htm> http://www.minuszerodegrees.net/bios/bios.htm) to have the option 47 user disk. Following the instructions given in the manual of the hard disk IBM H3256-A3 fields to be filled in bios are: cyl = 872, heads = 16, Wpcom = 65535, Lzone = 0, sect / trk = 36, obtaining a total capacity of 245.205 MB (=872x16x36x512/1048576). After turning on the machine, however, it stops and it does not proceed either boot from a floppy or even the keyboard responds any more. Instead without hard drive connected and / or configured the machine works perfectly. Thanks for any useful suggestion. Enrico

12 years, 11 months

Multicians wonder what terminal this might be

by jws＠jwsss.com

Tom Vanvleck posted this question about a terminal. I would have just sent it to Richard, but figured someone else might recognize it also. I got mail from someone asking about a terminal he had salvaged. I added the photo to the "photos" section of the gorup: http://groups.yahoo.com/group/multicians/photos/album/1199215560/pic/list If you are not a member of that group, I put the photo here: https://www.dropbox.com/lightbox/home/Public/multicians-photo It appears to be a VIP terminal.. he wrote The only thing I've found on Google that remotely resembles it, is in a Multics brochure from 1977, page 4: http://archive.computerhistory.org/resources/text/Honeywell/Honeywell.Level…

12 years, 11 months

Speaking of FPGAs...

by legalize＠xmission.com

This looks like an easy way to get started. <http://papilio.cc/index.php?n=Papilio.LogicStartMegaWing> <http://papilio.cc/uploads/Papilio/IntroToSpartanFPGABook.pdf> -- "The Direct3D Graphics Pipeline" free book <http://tinyurl.com/d3d-pipeline> The Computer Graphics Museum <http://computergraphicsmuseum.org> The Terminals Wiki <http://terminals.classiccmp.org> Legalize Adulthood! (my blog) <http://legalizeadulthood.wordpress.com>

12 years, 11 months

Box of old books

by db＠db.net

I've put together a small box of old TTL books, computer references of all sorts that I simply do not want anymore. If someone really wants to collect old databooks instead of me sending this stuff out to pulp let me know. It would be easiest if someone local to me here in Ottawa could deal with it. The other alternative is for me to get it moved to Toronto for someone else to deal with it. - Diane -- - db at FreeBSD.org db at db.net http://www.db.net/~db

12 years, 11 months

Apple IIe keyboard switches

by jules.richardson99＠gmail.com

I acquired an Apple IIe at the dump the other day (and a pair of IIgs machines, sans keyboards/mice - more on those later, probably). Something heavy has been dropped on the keyboard - there's no damage to the keytops (amazingly), but the keyboard PCB is cracked and the frame mounting points bent, and in testing switches around the damaged area I've found that the '=' key is permanently shorted (I assume it took the brunt of the impact from whatever-it-was, unless the switches in these machines are prone to decay and subsequent shorting). Anyway, is it just a case of desoldering the switch and prying it out of the metal frame, or is there more to it than that? I did try a little careful coaxing and it didn't want to move, but I don't want to try more force if it's the wrong approach. cheers Jules

12 years, 11 months

RRD50 Cable documentation

by rick＠rickmurphy.net

I'm in the process of trying to resurrect a MicroVAX-II system. I have a RRD50 cd reader and the associated KRQ50 controller. What I'm missing is the cable between the cabinet kit and the drive. I've tried various incantations, including a AUI cable (DA15 to DA15) and what I think is a straight-through cable. I also hooked the cabinet kit DA15M direct to the drive with no success. In most cases the drive spins up but when I try to boot it, the red error LED on the drive blinks then it spins down. So, I've got to build a cable. Does anyone have documentation of the pinout of what I need to build? Thanks, -Rick

12 years, 11 months

intel mds225 for sale

by tdk.knight＠gmail.com

one of the guys at my hackerspace has a intel mds 225 its power up to diag mode when the board is pulled from the back plane but when inserted the screen goes all fuzzed and crazy never been able to trouble shoot it gone over it with a meter pulled all cables boards out put them back in has pile of software and manuals and drawings to go with it and a prom rom programer reader and a another device of some sort http://www.flickr.com/photos/1ajs/6171038488/lightbox/ funds going to supporting a community hackerspace. if i was not broke i would just buy it myself to add to pegcity bits i can get a video of it powering up if anyone wants to see make offers o its located in winnipeg canada

12 years, 11 months

Well, that was depressing.

by jules.richardson99＠gmail.com

They just had an e-waste recycling event in town; different company to the one that did such an event once before. Last time I was allowed to check for vintage systems, but there wasn't anything useful there - just few-years-old PCs. This time around there was an entire dumpster full of vintage Apple hardware, but I wasn't allowed anywhere near it - it all goes back to Wisconsin for "processing". Apparently they do occasionally ebay some vintage items, but the way this lot had just been tossed into the dumpster makes me think that it's all off to the crusher. (and of course there was the Disk II drive that I need, sitting right on the top of the pile!) Of course it's their right to do what they want with it - it's just frustrating not being able to save any of it. Jules

12 years, 11 months

cctech Digest, Vol 117, Issue 2

by michael.99.thompson＠gmail.com

---------- Forwarded message ---------- > From: "Zane H. Healy" <healyzh at aracnet.com> > To: "General Discussion: On-Topic and Off-Topic Posts" < > cctalk at classiccmp.org> > Cc: > Date: Wed, 1 May 2013 14:48:41 -0700 > Subject: Re: Multicians wonder what terminal this might be > At 2:37 PM -0700 5/1/13, Jim Stephens wrote: > >> imgur is a bit confusing. try this. >> >> http://imgur.com/a/6FnnP >> > > Is it sitting on something, or is the base part of it? > > If the base isn't part of it, it reminds me of the TEMPEST terminals from > Honeywell that I used on a DPS-8. > > Zane > We had hundreds of those VIP screen-mode terminals connected to a Honeywell DPS-8 in Cambridge. The big blue box had a synchronous RS-232 port to connect to a multi-drop synchronous modem and eventually to the Datanet front-end processor. The serial protocol was special for the VIP. There were two COAX cables from the big blue box to the terminal, one for the keyboard and one for video. Some of the really old versions had mercury delay lines for the video memory. -- Michael Thompson

12 years, 11 months

Block-oriented Magnetic Tape Drives

by pbirkel＠gmail.com

All; I'm curious as to what other manufacturers/systems supported the use of block-oriented magnetic tape media along the lines of the DECtape (TU56) and DECassette (TU60) drives. In particular, what about the use of standard 1/2" tape media under such circumstances? A wear-n-tear problem given the multi-pass nature of this use (especially if being used to store temp-files for the OS), but if that scenario were avoided ... I'd like to play around with some, but acquiring either a DECtape or DECassette unit looks to be somewhere between impossible and merely seriously unaffordable -- not to mention obtaining media for use with either. So I'm thinking about whether there are possibly other drives out there for which I might construct a suitable controller to mediate between the raw(er) mechanism and the OS. Unlike a streaming tape unit I'd expect that a major consideration would be keeping the moment-of-inertia of the reels as low as possible, consistent with holding a sufficiently long tape at sufficient bit-density to achieve an economically-viable amount of storage per tape (*e.g*., 256Kb -- DECtape was 184K 12-bit words or 144K 18-bit words). DEC managed it; did anyone else? (Of course, if anyone has a lead on a DEC unit -- DECtape preferred -- I'm very interested.) Thanks for your thoughts! ----- paul

12 years, 11 months

Apple IIgs - IIe keyboard

by jules.richardson99＠gmail.com

As mentioned in my post about IIe keyswitches, I acquired a couple of IIgs machines at the same time as the IIe (along with an AppleColor RGB monitor) - but no ADB keyboards or mice. I've just checked over both systems; one has an Apple memory expansion board fitted (2MB, I think) and the other has a Harris GS Sauce memory expansion board (also 2MB via a pair of 1MB simms) and what I think is an Apple SCSI board (nifty!). Both seem to power up OK and sit there trying to boot from non-existent media (display via composite; I don't know if the CRT monitor works - it's on the to-do list to make a cable). Anyway, the machine with the SCSI card looks to be an earlier board, and has a keyboard socket soldered to the PCB. Wikipedia seems to suggest that this should accept the keyboard from my IIe, albeit with reduced functionality over a genuine ADB keyboard - however, is it as simple as plugging it in, or are there other tweaks that are necessary for it to work? (e.g. perhaps worst-case a ROM change for a ROM that I don't have!). Although I'd like to get an ADB keyboard and rodent, I'm curious to see if the IIe keyboard will work in the meantime... cheers Jules

12 years, 11 months

Two Maxell CS-600XD data cassettes for cost of shipping

by classiccmp＠crash.com

Anybody need actual official data cassettes? I've got two (2) free to anybody who wants to pay the cost of shipping - I'll use bubblewrap and toss them in the smallest USPS flat rate box, that's $5.80 last I checked. "Maxell High Density Data Cassette - 183 m / 600 ft. - 16,000 ftpi. - D/CAS-86 COMPATIBLE CS-600XD Made in Japan" Labels are blank, write-protect switch is in the protected position. Excellent condition, clean, not sure where I found them. PayPal preferred. --S.

12 years, 11 months

Imlac PDS-4 information?

by derschjo＠gmail.com

Long shot, but does anyone have any documentation or software for the Imlac PDS-4? I'm working on an Imlac emulator/simulator (for the -1 and -1D) and I'd like to support the -4 as well, as it appears to add some interesting options; problem is I'm not finding a lot of detailed information about what and how it works :). (Hardware documentation/schematics would also be interesting - I have a set of what appear to be PDS-4 core memory boards and I'd love to be able to debug them since they're in rough shape...) - Josh

12 years, 11 months

Kaypro System disks?

by dave13＠dunfield.com

>>> When you create 360/1.2M disks by formatting on the PC - can you then >>> read and recreate those disks with IMD? >> I tried reading and then recreating a DOS 360K disk. Worked fine. >> >> It even seemed to read a known good Kaypro disk. But, I tried writing >> it out with no luck. It did, though, write it out with no errors, so >> I think I have two issues. One is that the K10FLOAD.TD0 file that I >> converted to an IMD did not convert correctly, and the other is a lack >> of correct settings on IMD. >> >> When I read my known good DSDD Kaypro boot disk, I set tracks to 80, >> stepping to double, and sides to 2. But, IMD tries to read all the >> way up to track 80, when I thought it would stop at 40 (80 tracks, >> double stepped). >Update: I was able to copy a known good Universal ROM boot disk and >boot it on the K1. So, at least I know my setup works. I still don't >understand why the read of the disk tries and fails to read tracks 41-80 >with doublestepping on. I also don't understand why running td02imd on >k10fload.td0 didn't create a good imd file I can use with the utility. If you take the time to read/understand the IMD docs and/or help screens, you will note that I explicitly state that IMD does not make ANY assumptions about your drive. It simply uses the capabilities of the controller to see what it can find "out there". The point of note here is that it supports up to the theoretical maximum of 255 cylinders that the 765 controller architecturally supports. So why would it assume that your drive cannot have more than 80 physical cylinders. It has no idea what type of drive you have. Sure, drives with more than 80 cylinders aren't common, but sometimes extra data is hidden in an extra track beyond the end... Some times two tracks ... why may any such assumptions - At one time 8" drives with 77 cylinders were "as big as it gets" - so NEC designed a 77 step limit into the original 765 ... which means they fail on long seeks on more modern 80 cylinder drives - requiring software workarounds ... IMD makes no assumptions about the drive - it simply does what you ask it to do. When you set double-stepping, you are simply telling IMD to send two step pulses for each cylinder it wants to move the head. It will try to read the number of cylinders that you specify. It does not "guess" that your drive may not be big enough to contain those cylinders because of other settings that you have made. IMD is about doing what you ask it to do, not trying to "fix it up for you". If you want to read a 40-cylinder disk --- set it to read 40 cylinders. It defaults to 80 cylinders because that will read most comon disk types without the user having to actually know what he is doing. Most drives will allow seek a couple of tracks past the certified number of tracks. In *MOST* disks, these "extra" tracks will not contain any data. At it's default settings, IMD will stop when it encounters a track with no discernable data - in *most* cases, this signifies the end of data tracks on the disk. So if you read a 40 cylinder disk while set to read 80, it will read 0-39 and stop on track 40. But this is because it "ran out of tracks" when it hit the extra track (40 = track# 41). But... if the disk contains data in this area, IMD will happy continue reading up until it either runs out of data, or hits the specified cylinder limit. This is why some of my Kay disks have the extra SD track 40 -- the original disks actually have this track one step beyond the certified limit of the drive. It also means that if your drive does not step past the certified limit, or you have data in all of the "extra" tracks before it hits the stop, then it will continue to step, banging the head against the stop until it gets to the number of cylinders you specified (because it never runs out of tracks with data). I designed IMD to be a fairly powerful tool, and not to limit you by making assumptions about what you are doing - as a result, you have to know more details about what you are doing than "other" disk archival utilities ... I do provide a lot of useful information in my docs and help files to help you get it sorted out, but it does require an inventment in time/effort to get there. Which leads to the question ... if you have TeleDisk images for the disks you want to create, and are finding IMD unsuitable - why not use Teledisk to recreate the disks. TeleDisk is designed to "make it easy" - it looks at the BIOS settings to see what kind of drive it is, and makes decisions based on that - for basic operations, it will be simpler than IMD to use. Dave -- dave13 (at) Dave Dunfield dunfield System/Firmware development services: www.dunfield.com (dot) com Classic computers: http://www.classiccmp.org/dunfield

12 years, 11 months

Kaypro System disks?

by dave13＠dunfield.com

>> When I read my known good DSDD Kaypro boot disk, I set tracks to 80, >> stepping to double, and sides to 2. But, IMD tries to read all the way >> up to track 80, when I thought it would stop at 40 (80 tracks, double >> stepped). > >WHOA! >You asked for 80, and it tried to do 80. You seem to be assuming that it >would divide by the double-stepping and do 40. (Actually, it is prob'ly >planning to stop at #79, V #39) > >1) When IMD asks "tracks", is it asking >A. Cylinders of the disk format (AKA "tracks [per side]") >B. number of cylinders TIMES number of heads >C. cylinders of the DRIVE The setting is "Cylinders" in the main settings menu, and it indicates the maximum number of cylinders that IMD will attempt to read from the disk (when writing IMD uses the cylinders occuring in the image - unless you use the track exclusion feature to avoid writing certain ones). >But, are you sure that IMD is counting both sides of a cylinder as >separate tracks? >When dealing with hardware, it is not uncommon [albeit inaccurate] to >treat "track" and "cylinder" identically. >"1.2M drives are 80 track" V "360K drives are 80 track (40*2)" >"Directory is on track 4" usually does NOT mean cylinder#2, side B IMD uses "Cylinder" to refer to the actual cylinders - ie: actual steps of the head(s) - it uses the "Singe/Double sided" setting to determine how many tracks occur in each cylinder ("as read" means it will try to read both sides for the first few tracks to determine. >> But, when I set retry to 0, and it goes all the way up there, I still >> don't have a good copy. > >If retry is set to 0, then it won't even try again when it hits an error, >which is VERY common with floppy drives. >NOT GOOD for getting usable disks. A good default is 5 - 10 >In SOME programs, NO RETRIES is useful for TESTING, as ANY error, no >matter how soft will be reported. >In SOME programs, 1 - x are the normal values, and 0 is treated as a >special case, either as '0' means "never stop trying until you succeed", >which is useful for desperate recovery, or >in SOME programs, '0' is a special case, and just means 256, 65536, or >4294967296 (DEC CX JNZ...) In IMD 0 is a special case, but it means to quickly scan the disk getting what it can on one read and NOT to re-analyze the disk if it cannot read data from a track - in doing so it also prevents the automatic stop when data runs out ... it's just a quick way to scan the whole disk to check a particular format. Agreed is it not recommended as a way to get reliable disks. >BTW, Kaypro puts an INCORRECT value in the "Head Number" field of the >sector headers of all of the sectors on side B. Fortunately, like the >extraneous SD track that Dave encountered on the 41st cylinder (#40), it >is ignored in use. Both are irrelevant to the current project, but quite >important if you want to use INT13h to read, write, or format Kaypro >diskettes. They also use different sector numbers on side 1 - in fact, they logically number both sides as if it were a single side (head 0) with ascending sector numbers through the sectors on both sides. IMD simply records the cylinder, head and sector numbers found in the sector headers of any given physical track and recreates them as it writes the disk - it does not expect them to contain any particular value, so it reads/writes kaypro disks with no problems. Dave -- dave13 (at) Dave Dunfield dunfield System/Firmware development services: www.dunfield.com (dot) com Classic computers: http://www.classiccmp.org/dunfield

12 years, 11 months

First web site restoration

by Paul_Koning＠Dell.com

Saw this in a newspaper article: CERN has brought back to life the first website -- of 20 years ago. http://info.cern.ch/ paul

12 years, 11 months

R4400 SGI Indigo - wild roar shortly after power on.

by trasz＠FreeBSD.org

I have a broken SGI Indigo I'd like to fix, but I have no idea where to start. The most obvious problem is that shortly after power on - two seconds, maybe three - a noise starts coming from the internal speaker. The sound becomes louder and louder with every second. No startup chime, no output on serial console. My initial thought was a broken power supply, but a PSU repair guy I've found claims that power supply is ok and voltages are correct and clean. He also says that he tried to bend the "mainboard" - probably the CPU board - slightly and this sometimes leads to the startup chime. Any suggestions are welcome. Thanks :-) -- If you cut off my head, what would I say? Me and my head, or me and my body?

12 years, 11 months

Conventions/Shows in the NY/NJ/CT area

by curt＠atarimuseum.com

Anyone have a listing of shows coming up in the NY/NJ/CT area... Anything for computers and/or videogames... I would like to see about getting a vendor table to sell copies of the Atari Inc. book and to also sell my USB joysticks and my newer versions that are ready May 1st. Thanks. Curt

12 years, 11 months

Kaypro System disks?

by dave13＠dunfield.com

>Booted to DOS 5.0, on AT class machine, drive B set to 1.2MB, formats >and writes/reads disks fine. imd has been copied to HD, as well as IMD >image. >> >> If you are booting to real/raw DOS ... does the drive work under DOS.? >Yes >> Can you FORMAT 1.2M and 360k disks under DOS and read/write >> them.? If not, you have a hardware problem (for DOS, make sure it is >> configured correctly in BIOS - IMD doesn't use BIOS settings though). >Works fine When you create 360/1.2M disks by formatting on the PC - can you then read and recreate those disks with IMD? If yes, then likely your hardware setup is working. If no, then you may have some compatibility issue with the mainboard controller. (IMD does direct access to the FDC hardware) Fred's post below also reminded me that Kay disks are 10x512 - this can be "a bit tight" for some PC controllers. 765's and derivitives have a "blind spot" just after the index hole - and some versions are worse than others. Once you try to recreate a Kay disk and it fails ... try reading the first track back. Does it get most of the sectors. If the first or last sector is missing, then it likely held off writing the first sector long enough that the whole track with the "extra" sector didn't fit in the remainder of the track. If this happens, you could try slowing the drive down slightly ... you may be able to create a readable disk that way (I almost always have to slow my drives by a few rpm to write Cromemco disks for example). You might also make readable disks by reducing the gaps from the precalculated values.. a little experimentation may be in order. IIRC you indicated that you were using a Teac 1.2M drive - it might be jumperable for 300rpm ... if so, try that - running the controller at 250kbps might improve the situation. I find that generally recreating DD disks can be a little more forgiving with 300rpm drives. Dave -- dave13 (at) Dave Dunfield dunfield System/Firmware development services: www.dunfield.com (dot) com Classic computers: http://www.classiccmp.org/dunfield

12 years, 11 months

Kaypro System disks?

by dave13＠dunfield.com

>> >A further tip: when writing new floppies with IMD (to generate original Kaypro bundled >> >software for example), I found it easiest to Format the floppy under 22DISK first, as it >> >knows the correct settings for a Kaypro floppy, then use IMD to write to the formatted >> >floppy. Doing this meant the only setting I had to set on IMD is the Double Step (as I >> >have a 1.2MB (80 track) drive, not a 360KB (40 track) drive. >> Makes no sense. IMD knows the exact format of the particular disk that it is writing >> as this was determined at the time it was read, and is represented in the metadata >> of the IMD file - it also formats the disk as it writes it, removing any previous formatting. >> And ... if he's writing on a 1.2M drive (presumed in a HD controller) , he WILL need to >> set a 250->300kbps translation in addition to double-stepping in order to write the disks. >Could part of the confusion there be that >SOME 1.2M drives are 360RPM only, and therefore require the 300kbps >data transfer rate, and >SOME 1.2M drive are 360RPM/300RPM, and when in a 300RPM mode can use the >250Kbps data transfer rate? Is there a "standard" for setting drive speed? - I don't think I've encountered an actual dual speed HD drive setup in a PC (except for some of mine which have a manual "speed switch" on the front panel added by yours truly :-). IMD doesn't know anything about changing the drive speed as I have not seen documentation on this so if this is possible on some drives/controllers, then it might explain it - if 22disk had changed the speed of the drive. Dave -- dave13 (at) Dave Dunfield dunfield System/Firmware development services: www.dunfield.com (dot) com Classic computers: http://www.classiccmp.org/dunfield

12 years, 11 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