test-drb July 2003

test-drb@ccmp.vtda.org

279 participants
450 discussions

by palazzol＠comcast.net

Anyone else spot that one near the end of the movie? It was one of the 80-column models. Not sure what any of the other "30-year old" computers were. -Frank

21 years, 8 months

scanning booklets for archive

by classiccmp＠vintage-computer.com

> I finally have a scanning system setup here for archiving documents. On a tangentially related note, we've just started an effort at the VC Forum to track scanned documents. Think of it as an index to available online documents of interest to vintage computer collectors. It's just in its infancy, but I think it's a great idea and I hope we have success with it. The thread at http://www.vintage-computer.com/vcforum/viewtopic.php? t=241 covers my interpretation of the effort. I'm sure it will evolve somewhat over time. Please feel free to drop by and comment or help out! Thanks, Erik Klein www.vintage-computer.com/vcforum The Vintage Computer Forum

21 years, 8 months

Vairan Data Machines

by aek＠spies.com

I got a lot of manuals and schematics - I'll prepare a list. Since my brother got a powerful scanner at work, he might be able to scan the documents, which are not at your site already. -- I have quite a bit of material also which I will put up now that there is someone who needs it. What I don't have that would be very handy would be documentation on the fixed head disc, and disc interface.

21 years, 8 months

Varian Data Machines

by aek＠spies.com

I got a Varian(Univac) Data Machines 620L100 in very good conditions including a fixed-head disk, a teletype and a Tektronix storage display. This machines is dated to 1974. -- Is it an ADAPTS system (is there an A/D panel just below the CPU) ? I have one. It is very likely that there is a lab oriented BASIC (possibly still in core!) If there is any way to save the contents of memory before you fiddle with trying programs, it would be a GOOD THING. I haven't touched my machine because I don't want to destroy what may be the only copy of that program. I would also suggest not spinning up the disc right away. I assume you aren't getting any documentation or external software with it?

21 years, 8 months

Data Systems Design DSD-880 8" floppy and hard drive?

by pete＠dunnington.u-net.com

On Jul 23, 1:34, <rogersda(a)cox.net> wrote: > Jerome Fine <jhfinexgs2(a)compsys.to> wrote: > > > [...] In addition, > > I also added a bounce buffer in DYX.SYS so that > > a user buffer above 256 KBytes could be used > > with the 18-bit hardware addresses in the floppy. > > Actually, for device I/O, it doesn't matter whether > one is using 16, 18, or 22 bit addressing. The PDP-11 > I/O page is defined as from 28KW-32KW, which is entirely > within the range of 16bit addressing. It's true that the I/O page always appears *to software* at *logical* addresses 160000-177777. This is fine for the processor, which has logic to deal with it. Nevertheless, the *hardware* addresses which appear on the bus need to be 160000-177777, 760000-777777, or 17760000-17777777 depending on whether the system uses 16, 18, or 22-bit addressing. To make life easier, DEC provide a "Bus Bank Select 7" signal, which most I/O devices use to detect access to the I/O page. What Jerome is referring to, however, is the DMA operation. An RXV21 or RLV11 (and some other devices) can only perform data transfers to 18-bit addresses. Data is transferred only by DMA; you can't transfer data from the device controller, only commands and status. Most DEC operating systems expect data transfers to be able to load/save from data buffers at arbitrary (physical) addresses; therefore drivers in some operating systems have the option to use a bounce buffer mapped to low memory, for 18-bit devices. They therefore transfer the data in two stages: under program control between the bounce buffer and the required address, and letting the DMA transfer between bounce buffer and actual device. -- Pete Peter Turnbull Network Manager University of York

21 years, 8 months

Data Systems Design DSD-880 8" floppy and hard drive?

by rogersda＠cox.net

Jerome Fine <jhfinexgs2(a)compsys.to> wrote: > I agree there needs to be a SYSGEN to be able to use > all 3 * RL02 drives with the DL(X).SYS device drivers > and the hardware handles ONLY 18 bit addresses for > both the DYX.SYS and DLX.SYS device drivers. > > BUT the RLV11 and the RXV12 from DEC also > managed to handle only 18-bit addresses. So the > DSD box was completely compatible with the stock > (distributed) V4.00 of RT-11. > > However, V4.00 code in DY.MAC contained the > extra instructions to use a double-sided media which > would probably have been called an RX03. And > although those extra instructions had bugs (after all > they had never been tested) and were removed by > V5.00 of RT-11, I did fix the bugs and ran a DYX.SYS > device driver under V5.03 of RT-11 using the DSD > 8" floppy as a double-sided drive. In addition, > I also added a bounce buffer in DYX.SYS so that > a user buffer above 256 KBytes could be used > with the 18-bit hardware addresses in the floppy. Actually, for device I/O, it doesn't matter whether one is using 16, 18, or 22 bit addressing. The PDP-11 I/O page is defined as from 28KW-32KW, which is entirely within the range of 16bit addressing. Dale Rogers DEC/Compaq/HP

21 years, 8 months

Website down?

by kurtk7＠visi.com

Just a quick question for the group, Anyone heard of a website called olddos.org? Thanks Kurt

21 years, 8 months

DEC AD0L-A

by wrljet＠yahoo.com

Does anyone know what a DEC AD0L-A is? Looks like some sort of A/D equipment. Mounting panel holds a number cards and has a small power supply near one end. Cards present (looks like a bunch are missing, from the amount of wiring on the backplane) are: A220 A708 A862 bipolar high speed A/C convertor G701 M100 M111 invertors M161 binary to octal convertor M216 flip-flops M602 pulse generator M636 Anybody know what the mystery cards are? Thanks, Bill

21 years, 8 months

apology for the delay

by jwest＠classiccmp.org

Sorry all the email got backed up on cctech for a few days. I just got back >from the Great Oklahoma Excersion(tm) with Guy to pick up Jeff Sharp's collection - hence I was away from the list for a few days. God was Oklahoma HOT!!! Lots of pictures of the move were taken. I'm shipping my pictures off to Guy and he'll put them up on his website sometime I'm sure. Regards, Jay West

21 years, 8 months

Dec RA60 Drives and HSC40 Controller... worth rescuing?

by rogersda＠cox.net

The RA60's should be opened with power on. However, unlike RL02's, the solenoid can be overridden with a thin blade. > From: Corda Albert J DLVA <CordaAJ(a)NSWC.NAVY.MIL> > ... As I recently acquired a VAX6630, I am considering > latching onto the HSC40, but am vacillating on the drives... You have to really *want* one of these. They are power hungry little beasties. > they _are_ heavy, and the dealer has no disk packs unless, > god forbid, they are still in the drives 8-( ... I need to go > back sometime this week and open 'em up for a look-see. > > Not being familiar with the RA60, and being unable to find any > docs on-line, I have no idea how to open these up... does anyone > have any experience with these critters? Can they > be opened without power (i.e. is the top door locked with a > solenoid?) As far as what to look for, hold the pack so that light is passing through the side of it. Every surface should be completely smooth. If you see any rings, it's had the head touch it. The heads should be white to yellowish white with a dark bar in the middle. If there are black or brown smudges on the head, they've been crashed. If they clean up smooth with 95% alcohol, they ~may~ be okay. I'd have to look, but I think good heads ohmed out at 4-6 ohms. (It's been a while since I last worked on one.) Dale the DECdude

21 years, 8 months

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test-drb July 2003