test-drb November 1999

test-drb@ccmp.vtda.org

211 participants
749 discussions

D--16 Maintenance Manuals? Someone needed them?

by dylanb＠sympatico.ca

I have two maintenance manuals for the D-116. Someone requested these a while ago from this list but I cannot locate the email from him. Please e-mail me so I can ship them out. The first manual is part I (CPU handbook), the other manual is full schematics. PDP-8s and other rare mini computers http://www.pdp8.com

24 years, 5 months

IBM P70-386 portable machines

by mrbill＠mrbill.net

I took out my pair of these tonight to see what level of functionality they're in. One of them gives a "dead HD" error on bootup (see http://www.geocities.com/SiliconValley/Lab/6370/errores.html) which was confirmed by downloading the boot/diagnostics disk and firing it up with that (see http://www.geocities.com/SiliconValley/Lab/6370/models.html for disks, if you've got a PS/2 that needs them). Turns out one of these also has the 300/1200/2400 modem and the PS/2 (MCA-bus, woah, in a portable!) SCSI card w/cache (its got two SIMM sticking on it, even). Right now I cant figure out how to get the HD out of the machine so I can swap it with the one from the other box (or possibly replace it with another IBM drive, these look to be the proprietaary PS/2 card-edge- connector HDs). Anybody got one or more of these machines that they'd like to "dispose" of, if I pay shipping? I love the red plasma display, and plan to use this box (if I can get it fully working with a HD) on my packet radio station. I've got this other semi-DOA (no screen display, no beeps, but power lights) 70-386, and in the garage somewhere, a complete (no manuals, but it boots and works, and has the I/O expansion "slice") IBM PC Convertible laptop, with power supply in IBm canvase carrying case, if anybody's interested and wants to swap something for them. I've also got this MCA-bus SCSI controller card w/cache, if that would prove useful to anyone... (I cant use it, it has the funky IBM-proprietary external SCSI connector on back). Bill (man, plasma displays are wonderful, wish I could find more machines that used them.. I've already got a couple of Toshiba 3x00 laptops that i use as VT100 terminals; anybody else know of portable machines that used similar displays?) -- Bill Bradford * mrbill(a)mrbill.net / http://www.mrbill.net mrbill(a)sunhelp.org / http://www.sunhelp.org --------------------------------------------------------------------- "Fear leads to anger. Anger leads to hate. Hate leads to using Windows NT for mission-critical applications." -- What Yoda *meant* to say

24 years, 5 months

Whats the screwiest thing you collect?

by SUPRDAVE＠aol.com

In a message dated 11/26/99 11:23:32 PM Eastern Standard Time, edick(a)idcomm.com wrote about collecting train stuff, saying: > OOOHH! N-scale! Nice stuff, even for the apartment dweller. actually, Z-scale is better. you can run a coupla loops around on a shelf! of course, miniturization <sic> costs money...

24 years, 5 months

CP/M-80 drivers for WD33C93 ???

by allisonp＠world.std.com

<Actually, the ACB4070 is a SCSI<=>RLL bridge. It operates in a way which I have one in use but it's been a long while since I did it. <translates what is on the disk to cyl/hd/sector. However, it talks to the <host in SCSI. In any case, I've seen implementations (back when they wer Yes but when you talk from the host is it CHS or BLOCKS? If memory serves you init the controller with the disk geometry and it translates that to a sequence of blocks where the physical geometry is not directly visible. <all over the place) which worked very well, and I've seen others which <worked very poorly. Insofar as the bridge controllers were the same, I hav <to assume that it was because of the BIOS code. I should have informed <myself about that back then, but it didn't seem important enough. They are not all the same performance wise. Some are realll sloowwww. Also it also depends on the host interface and IO. If the SCSI hardware is faked or a bit doggy it shows. <Many ESDI drives work on a logical block basis just like the SCSI's. They Cool, never worked with them. <one to shuffle the data between the host and drive. The thing that makes <SCSI outperform ESDI in most cases is that the SCSI leaves the host adapte <alone except when it's transferring corrected data. The ESDI relies on th <controller to handle all the correction, etc. In an environment, e.g. DEC' <MSCP, where there are enough smarts to utilize command queueing and <overlapped seeks, etc, SCSI outperforms the fastest ESDI by quite a little .... and? I know the VAX MSCP controllers I must have 5 or 6 RQDX3/2/1s I still run. <>Watch out for track (one head) and cylinder (n many heads). < <It seems that if the BDOS is willing to call out both the track and the <sector numbers in a range from 0..FFFFH, that means you only need to specif Correct both are passed as 16bit numbers in the BC pair. <one sector per track if all you want is a logical block (physical sector) <number. You then right-shift to scale for the physical sector size and the <let the deblocking code wade through undoing that. FFFFH sectors is the 8M <max allowable capacity, is it not? The bridge controller translates from I said all this already. <logical block numbers to cyl/hd/sec in some way they don't choose to tell u <mere mortals. It's not that majik, the bridge know the physical geometry passed on init and the rest is math. <OTOH, using the BDOS to do more of the work, sorta, you can map tracks int <logical blocks, and use the sector number to point into the logical block a <the appropriate 128-byte portion. What I'd like to know is what works best <It's particularly important that this be small, since it's for CP/M 2.2. I gave a few suggestions. Let the BDOS do the minimum, it's slow and written using 8080 code. the real space eater is not the code to do this but the allocation space. For a 8mb disk with 4k allocation that will want 256bytes!, then there is the dir vector (another 128) deblock buffer (512bytes or physical if different) so you have already used up 768bytes and not written any code. Oh, you need to have a unique allocation space for EVERY disk and if it's removable also CHK space that is half the size of the allocation space and also unique. <>to that to get the track offest for partitioning or system tracks. < < <What do you find this does to your directory allocation scheme? I've neve <quite figured out how to optimize the block size so you don't either run ou <of directory entries or disk space far too soon. That is a limitation of CPM. Block size affects the size of the 1byte file. By that it limits the number of files on a disk if they are of minimum size. for our 8mb disk you can use 2/4/8/16(32)k. If you use the smaller the allocation space is 512bytes in size, use the larger(16k) it will be 64 bytes so you have a tradeoff there. Assume 4k block, that means the largest number of files is 2047 so that limits the number of possible directory entries on the high side. from there you have to know how the disk space will likely be used and for many 2 blocks per file is a usable number so we are now down to 1024 directory entries. From that we know an entry is 32bytes and an allocation block slected is 4k or 128 entries so we will need 8 directory blocks to hold our directory. Done. Of course we can assume we need 4 blocks for each file and use half the number of directory blocks. This is a guess. <Actually, it's a 99.25 MB disk. It's a miniscribe 3085 used with RLL. <Since I have one of these lying about, and since the 4070 is an RLL bridge <I thought I'd use those numbers. You would have to partition it into 13 logical drives. Hint: don't mount more than two or three at any time and create a MOUNT utility to select what partitionis active and plug inthe tables for it. The amproLB bios is a good choice for this. The number of logical drives including floppies is a determining factor in BIOS size as you need the various Buffers and Allocation Spaces (8 8mb drives at 4k would eat 2k of allocation space!).

24 years, 5 months

Obsolete media (was: Whats the screwiest thing you

by allisonp＠world.std.com

<There's always the well-known kludge method. You get a 3-phase motor <somewhat larger than the one you want to run (any such induction motor <should work). You energise one winding from single-phase mains, using a <capacitor to generate enough phase shift to another motor winding for it <to start and run. Then use all the motor terminals as a 3-phase output to <the motor you want to run. Effectively this new motor becomes a rotary <converter. < <I assume the motors in disk drives are not that large, so this may well <work. It's certainly been done for (small) lathe motors. I've seen this done for motors in the 3-5HP range! Allison

24 years, 5 months

PDP-11 Processor Handbook?

by mcquiggi＠sfu.ca

Hi Brian: At 06:49 PM 11/28/99 -0500, you wrote: >I think it's great what you're doing -- digitizing PDP-8 docs for public >use, however my main interest is the PDP-11, so I was wondering if you >have a PDP-11 Processor Handbook (preferably one that relates to the >PDP-11/45) that you plan on digitizing? Thanks. Thanks! Credit for the scanning goes to others, I just manitain the web site. I don't have anything on the pdp-11 in electronic form. Rich Cini specializes in pdp-11 stuff, he has an account on highgate too. See http://highgate.comm.sfu.ca/~rcini to see what he currently has online. I've cc-ed him on this message so you can talk directly if necessary. You could also ask on the classiccmp list: classiccmp(a)u.washington.edu, or on the pdp-11 list: info-pdp11(a)village.org List folks: can anybody help this fellow with an electronic format processor handbook? Good luck, Kevin > > > ========================================================== Sgt. Kevin McQuiggin, Vancouver Police Department E-Comm Project (604) 215-5095; Cell: (604) 868-0544 Email: mcquiggi(a)sfu.ca

24 years, 5 months

Obsolete media (was: Whats the screwiest thing you collect?)

by ethan_dicks＠yahoo.com

--- Dave McGuire <mcguire(a)neurotica.com> wrote: > On Sun, 28 Nov 1999, Richard Erlacher wrote: > >Since the GOV also loved DEC, I'd be very surprised to learn that there's no > >practical implementation available of the EXB8200 on a DEC machine... > > They do exist...I have a couple of subsystems here which have Exabyte > drives in them (unmodified, regular SCSI drives) with bridge boards which > go to SDI connectors on the other side. We had a few of them on the VAXcluster at Lucent. Screwy damn things... you had to double-tap one of the bridge-card buttons to unload the tapes; they wouldn't unload with the internal eject button nor under VMS control. I myself have more than one 8200. If anyone is looking, let me know. -ethan ===== Infinet has been sold. The domain is going away in February. Please send all replies to erd(a)iname.com __________________________________________________ Do You Yahoo!? Thousands of Stores. Millions of Products. All in one place. Yahoo! Shopping: http://shopping.yahoo.com

24 years, 5 months

Obsolete media (was: Whats the screwiest thing you collect?)

by allisonp＠world.std.com

<Unless there is no equivalent... I've got the exact problem with the <DECsystem-10 I got earlier this year... it came with two RP06 drives. <They are 3-phase drives. We don't yet have three phase power (or a <close approximation of it), so cannot run the drives. Without the <drives, we cannot even load the microcode for the machine, so it is <a very large paper-weight. < <I've been looking of a non-three-phase replacement for the drives, but <we still would need three-phase to get the data off the disks I have. Why not a rotary phase converter, not the most efficient but buildable. That would allow running the drive off a single phase ckt that is heavey enough to take the load. Allison

24 years, 5 months

DEC Qbus Card

by ndiablo＠diablonet.net

Hi! I'm not sure offhand what the card is, but you might want to check the Visual Field Guide at http://vaxarchive.org - it has a lot of information useful in regard to identifying and configuring a lot of QBus cards. -Sean Caron (root(a)diablonet.net)

24 years, 5 months

Whats the screwiest thing you collect?

by SUPRDAVE＠aol.com

as for myself, beer cans and antique outboard motors 1960 and earlier. In a message dated 11/26/99 4:21:43 PM Eastern Standard Time, jim(a)calico.litterbox.com writes: > Um... Swords. And Anime Cels. Old PCs seem to follow me home, but they > either > get taken apart and recombined into useful machines or thrown out, so I > wouldn't > call them a collection. > > > > I am just wondering what some of us collect that we consider the > screwiest > > > ourselves. For example, for reasons I can't fathom I have started > > > collecting Apple logo AC power cords, and have a couple dozen of various > > > styles now. > > > > > > > > > > > -- > Jim Strickland > jim(a)DIESPAMMERSCUMcalico.litterbox.com

24 years, 5 months

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test-drb November 1999