test-drb April 2004

test-drb@ccmp.vtda.org

248 participants
481 discussions

Re. HP64000, aka offering help to duplicate HP64K disquettes

by RMaxwell＠atlantissi.com

Terry, I contacted Michel Bissonette regarding his post: his MS-DOS utility could duplicate HP64000 floppies, but made no effort at extracting content. Since I wanted to port the data to DOS, it wasn't what I needed. I have been recovering HP64000 files from floppies written by a 64000 that no longer boots. To save myself from too much low-level programming, I've been using a Kaypro 4/84 to do the first stage: it has MFDISK, a multi-format utility that reads HP-125 CP/M disks, which happen to have the same track/sector/low level layout as the 64000 format. With a quasi-compatible link to the low level, I use DUU (V8.7), a CP/M utility that allows read/write/view access to the tracks and sectors. This allows me to access the directory (completely incompatible with CP/M or DOS), locate the files' start- and end-points, and trace their content along the disk. HP64000 data are in 2044-byte sectors, with an additional two byte pointer to the previous sector at the start, and another two bytes at the end pointing to the next sector (total 2048). DUU just copies sectors verbatim to a native Kaypro CP/M disk via a RAM buffer (files bigger than 32K come out in chunks due to the fact that DUU, CP/M and the buffer all share one 64K RAM space). Kaypro CP/M disk files port to MS-DOS using the 22DSK utility (incidentally, 22DSK's HP-125 emulation doesn't help on HP64000 disks, because the first thing it looks for is the CP/M directory). I have quick-and-dirty Turbo Pascal conversion programs that extract ASCII-format text from editor files, and binary images from assembler objects: each editor record ("line") of a file starts with a byte indicating the length of the PREVIOUS record and a second byte indicating the length of the CURRENT one. Line lengths are measured in 16-bit words - the editor pads odd-length lines with a space character. Lengths of zero mark beginning-of-file in the previous-length byte, and end-of-file for the current-length byte. This clever technique allows an editor to move quickly back and forth through a file line-by-line, but would get seriously messed up if it lost synchronization. I have technical details of where I found directory entries, what I've decoded and how the operating system refers to individual sectors and can provide you with that, probably best if I do that off-list (unless somebody REALLY wants it posted!). Now that I've detailed my less-than-direct solution, I'm waiting for some enterprising person who's willing to do the low-level floppy operations on a PC so one machine can do the whole thing in a step... Bob Maxwell > -----Original Message----- > > From: Terry Barnaby <terry(a)beam.ltd.uk> > Subject: Re. HP64000, aka offering help to duplicate HP64K disquettes > > Hi, > > I noticed a post you made some time ago about recovering files from > old HP64000 5.25inch floppy disks. > I have the same problem, some old HP64000 floppies which I would > like to get the contents off. > I would be gratefull for any information on the HP64000 disk format > and any tools you found to do this. > > Cheers > > Terry > -- > Dr Terry Barnaby BEAM Ltd > Phone: +44 1454 324512 Northavon Business > Center, Dean Rd > Fax: +44 1454 313172 Yate, Bristol, BS37 5NH, UK > Email: terry(a)beam.ltd.uk Web: www.beam.ltd.uk > BEAM for: Visually Impaired X-Terminals, Parallel Processing, Software > "Tandems are twice the fun !" > > > ------------------------------

20 years, 7 months

tu58 - reading off end of reel?

by XNEDAF＠aol.com

Brad, Where were you able to find the TU 58 capstan rollers, I have four TU 58 drives, and they all need new capstan rollers. I would certainly appreciate any help or direction you can offer. Thanking you in advance for your help. Steve Faden xnedaf(a)aol.com

20 years, 7 months

Mac Plus with (minor) issues

by cb＠mythtech.net

Sounds like the barrel rectifier at position CR5 on the analog board is going bad. Tech book I have here says its a MR824 rectifier. I had to look up the position and the part number in a book I have (Dead Mac Scrolls), but I have done this repair on a few Mac Pluses (same analog board as the 128 and 512), and they had similar symptoms. They had the Chirping noise, as well as the right side of the screen would move in and out (which would appear that everything is shifted left like you describe). Notes from the book. Original rectifier is a GI854, R-SI, 600V, 3A... and they recommend replacing it with a MR824, R-SI, 400V, 5A to avoid having the problem come back. The rectifier is kind of top center of the analog board. The analog board from those Macs was notoriously flaky. Lots of under rated parts that burned out easily. Probably Apple worst power supplies. Ironically, the 2nd worst are the CRT iMacs that brought back that same style computer. And ironically, the iMacs are bad for the same reason, under rated components that burned out from normal use. You would think Apple would have been more careful the 2nd time around :-) BTW: While you are in there working on the analog board, check and possibly resolder joint J4 on the main cable on the center of the board. Its pin 1 on the cable. That joint was bad on I think EVERY Mac Plus I worked on. So there is a pretty good bet that even if you aren't having problems with yours now, you will in the future. The solder would split off the board causing the cable to lose connection, causing the video to blink out. Smacking the side of the case would cause it to restore temporarily... its the only time I've had a computer company give me an official "repair" of "whack the side of the case" =:-O -chris <http://www.mythtech.net>

20 years, 7 months

Mac Plus with (minor) issues

by mtapley＠swri.edu

All, Two separate (?) issues with my Mac Plus. 1) Screen display is too far to the left. 2) System seems *very* sensitive to voltage setting. What I've got: Mac Plus (upgraded from 512k), original mouse/KB Brainstorm 16MHz 68000 upgrade Kensington System Saver Mac (switch, fan, and surge protector, mounts on top of system). La Cie external SCSI hard drive, 230 MBytes Analog (Radio Shack, automatically suspect) VOM. Mac OS 6.0.8, 7.0.1, 7.1 (chosen by System Picker utility) all on HD Screen Display issue: Everything (all pixels) is shifted uniformly to the left about 5 mm. I found the "width" setting on the analog board (well duh, read the label on the cardboard shield) and fooled with it (system on, plastic tool). Works fine, image gets narrower and wider. I can set it narrow enough that pixels are all on the phosphor, so the system is usable - but it's aesthetically slightly annoying to have everything to the left of where I expect it. I could not find a setting to shift left/right. Problem is present either with or without the Brainstorm installed, so I don't think it's related to that. I *think* the problem first appeared when I took out the "Elf Armor" mu-metal ELF shield that I got back when that was hot psuedo-science, my wife used the machine a lot, and we were expecting our first child (see the connection? :-) ). Significance of that is I had to unplug the cable >from the back of the CRT, so might I have knocked something askew? Voltage sensitivity: System started occasionally resetting itself. Opened it up, stuck the VOM on ground (frame) and 5 V (using the pin in the middle of the Analog -> Digital board connector, at the digital board) and found it reading a *little* (maybe 0.05 V?) shy of 5 V. OK, (duh, read the label on the cardboard analog board shield again) set the voltage higher, with system running. I can set it quite a bit higher, up to around 5.1 V. System keeps running. However, when I power-cycle at that setting, it goes into an endless loop of "chirp, chirp, chirp..." and the VOM stays near 0 V (wiggling at each chirp). I assume that means there's an overshoot on 5V coming up which triggers the crowbar, which sets up for a repeat. Q1) Is that supposed to work that way? I'd expected the 5V rise to be critically damped or better, so no overshoot. In other words, I'd expect if it'll continue to run at a given Voltage setting, it'll start at that setting. Have I got a latent problem forming? OK, sooo... set the Voltage back down some, try the "reset" button.. (repeat a few times) ... "Bong" ... starts up nicely ... runs a while and then freezes. (Here and below, "freezes" means some sort of bad instruction. Could result in lock-up, could mean drop into MacsBug, unable to continue, could mean reset.) This behaviour is not present unless the Brainstorm is installed (at least not obviously. It could be true but with a longer time constant between freezes). Sigh. So try setting Voltage barely higher. Works, but freezes *sooner*. Hmmm. Voltage lower. Works better. Voltage lower. Finally found a setting very slightly below 5V, (mmmm..maybe 4.98 V?? But remember the instrument I'm reading from here...probably about 1 significant figure) where it seems to run indefinitely ('til bedtime, anyhow). Q2) I thought that all digital stuff basically ran better until it over-voltaged - which the crowbar was supposed to prevent. So I'm surprised to see freezes/crashes at *higher* voltages (but still low enough to avoid the start-up overshoot) but see them less frequently at lower voltages. Q3) I assume there is a minimum voltage at which I'll also start to see freezes/lockups. True? Am I better off hunting for the lowest possible voltage, or try to find a "happy medium"? Q4) Have I got some incipient problem (dying isolation cap?) that is closing my window of working voltages? Warning: I'm on digest mode, the system is at home and I'm usually at work while accessing email, so my response time is likely to be ~24 hours for anything that requires tests/measurements. And then there's the kids' YMCA soccer (football) league .... TIA and no urgency, as the system appears to be running at the moment (raps forehead soundly) 'Knock on wood'. Kids are getting hooked on "Sim City" while I'm at work. But the Brainstorm may cure that...Sim City appears to run twice as fast with the 16MHz upgrade as it did with just the original 8MHz processor. Which reminds me: The Brainstorm is on a little daughterboard with 2 other IC's. The daughterboard plugs into a socket which is installed piggyback atop the original 8MHz 68000. There is also a flying resistor that solders to one leg of another component a short way away on the motherboard. If I pull the Brainstorm daughterboard off, and desolder the resistor lead, the system works just as before, with the 8 MHz CPU. If I plug the Brainstorm into the socket and connect the resistor, the system runs (see above, sometimes) at 16MHz (apparently). (FWIW, there are a couple of other modifications to the motherboard. I *think* they are just IC replacements.) I *think* this means that when the Brainstorm is plugged in, both 8MHz and 16MHz processers are running simultaneously. Bonus Q5) Is that right? Isn't that a recipe for thermal and electrical disaster? (I guess not, it runs, but....) -- - Mark 210-522-6025, page 888-733-0967

20 years, 7 months

TOA Manual..

by jeklopf＠COCACOLAOZARKS.COM

Chris, I was just looking through the net looking for a manual for a TOA A-912 and saw you had one in 2002. You had posted a message indicating it was up for grabs. I was wondering if you still had it or a copy. We have one at our company and no manual. We are changing phone systems and have no idea how thw A912 interfaces with the phone system we have now. Any info is appreciated... John E. Klopfenstein Network Administrator Ozarks Coca-Cola/Dr Pepper Bottling Co. 417-865-9900 ext 355 jeklopf(a)cocacolaozarks.com ---------------------------------------------------------------------------- ---------- FIGHT BACK AGAINST SPAM! Download Spam Inspector, the Award Winning Anti-Spam Filter http://mail.giantcompany.com

20 years, 7 months

Monitor/Video Cable Information for HP9000/300 needed

by bernd＠kopriva.de

Hi, i got a small lot of HP9000 stuff, including amongst other things a HP9133 (that's the reason, why i took it), and a HP 9000/300 and a HP35731A monitor. The HP9000 has a HP98456A included. Unfortunately, there was no cable included. What cable do i need for either the builtin video adapter or the HP98456A ? Can a HP35741A monitor be used too ? Thanks Bernd

20 years, 7 months

tu58 - reading off end of reel?

by dwight.elvey＠amd.com

>From: "Jay West" <jwest(a)classiccmp.org> > >Speaking of which.... > >I have two TU58 drives, both have a bad set of rollers. One is built into >the 11/44 cabinet, one is a standalone desktop version. I decided to follow >the "tygon tubing solution", but haven't actually done it yet. I have two >questions: > >1) What is the best way to cut the tubing to get nice clean round edges? I >tried to make a slice, but the tube gets bent/flattened due to the pressing >down of the blade so the resulting cut is "oval". Some kind of hot >wire/knife maybe? Gently sawing would leave jagged edges... ideas? Hi Try rolling it with a blade. Don't try to cut all the way though on each pass, just cut a little deeper. > >2) The old gummy roller comes off, but there is still some gunk left on the >metal capstan center. I could put the tube over this, but it may slip a bit >perhaps. Is there a good way to get the final remaining goo off the capstan? >I'm afraid to scrub it or anything for fear of damaging the tachometer hub. > Clean it off! Try various solvents. Dwight >Oh, and also, anyone have a good source for blank media for the TU58? > >Thanks! > >Jay West > >--- >[This E-mail scanned for viruses by Declude Virus] > >

20 years, 7 months

cctalk Digest, Vol 8, Issue 56

by mtapley＠swri.edu

At 12:00 -0500 4/29/04, Teo Zenios wrote: >I can toss the card onto my scanner and get a jpg of it (matrox card). I >never seen one until it came up for sale on ebay, trying to find some vram >to max it out at 4mb. I have forgotten, did we ever have a discussion about whether scanners/photocopiers/etc. have enough UV content in their lights to erase UV-EPROMs, if the sticker has come off? I sort-of recall we did, but don't remember the outcome. -- - Mark 210-522-6025, page 888-733-0967

20 years, 7 months

More DEC equipment spotted in Kansas City

by mmcfadden＠cmh.edu

If anybody is interested Surplus Exchange as multiple racks labeled VAX 6000-610 VAX 6000-410 Multiple 9-track tape drives One labeled TU58 They came from local engineering firm. Contact is Dave at Surplus Exchange. I can privately email you a phone number if you want to contact him. Mike

20 years, 7 months

FW: DEC VAX 785 and PDP11/70's in Kansas City

by mmcfadden＠cmh.edu

Update: I'm going over Monday morning and examining all of the systems and I will attempt to make a list and post it. I have to sign a donation letter otherwise the systems are mine. Mike >Subject: DEC VAX 785 and PDP11/70's in Kansas City >I just got word from a friend that a company in Kansas City is planning to >dispose of the following. > >DEC VAX 785 in three 6' cabinets >DEC PDP 11/70 in ten 6' cabinets, this may be two computers >4 RM03 disk drives >2 TU80 tape drives >Other disks for VAX >That is what they remembered without actually having a list. > >I'm trying to set up a time to actually see them. > >Here is the other information I have received. > >There is a company from Topeka that will take them away if they are paid to >remove them. > >The 785 was running 3 months ago when they erased all of the media. >It has been about a year since the 11/70's were on. > >They are not currently running. > >They are checking on the legal requirements that they may have to go through >to dispose of these units. >They are worried about making sure they aren't legally libel if somebody >dumps them improperly. > >Whoever takes them away may have to be a GE approved vender. > >I'll keep everybody informed. > >Thanks >Mike

20 years, 7 months

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test-drb April 2004