test-drb

test-drb@ccmp.vtda.org

101090 discussions

by steverob＠hotoffice.com

On Saturday, April 17, 1999 7:43 PM, Christian Fandt [SMTP:cfandt@netsync.net] wrote: > Upon the date 12:02 AM 4/17/99 -0700, Bruce Lane said something like: > > > > > HOWEVER -- Am I the only one getting -really- fed up with all the 'OT:' > >and 'Re: OT' subject lines and off-topic messages? > Ditto! Steve Robertson - <steverob(a)hotoffice.com>

26 years, 8 months

shipping floppy disk drives

by pete＠dunnington.u-net.com

On Apr 17, 22:32, Bill Yakowenko wrote: > Subject: shipping floppy disk drives > I'll be shipping a few floppy disk drives soon, and want to minimize > the shipping damage to them. So, is it better to ship them with the > drive door open or closed? And with or without a floppy inserted? If they're single-sided, it doesn't matter much. If double-sided, then open with no disk is fine, so long as the mechanism can't be jolted into letting the upper head hit the lower one. This is pretty well true of most 3.5" drives, and they're usually shipped like that. On some 5.25" drives, though, the door or lever could be moved, so inserting a floppy and closing the door may be better. I'd suggest putting it in back-to-front (or use a sheet of thick card with a hole in the middle) to improve the cushioning effect. -- Pete Peter Turnbull Dept. of Computer Science University of York

26 years, 8 months

Apple HAL XEBEC controller

by pete＠dunnington.u-net.com

On Apr 17, 13:57, Sellam Ismail wrote: > Subject: Re: Apple HAL XEBEC controller > On Sat, 17 Apr 1999, Pete Turnbull wrote: > > > Does it need any other software (like a formatting disk)? The on-board 4K > > EPROM contains only the strings "(C) HAL COMPUTERS LTD 1983", "A/XHAL > > SHARED RESOURCE WINCHESTER SYSTEM", "NOT CONNECTED", and "SRS ERROR", so I > > guess there would have been a floppy with it, originally. > > What in these strings leads you to believe it would have been connected to > a floppy? It was strictly a hard drive interface. Erm, nothing, Sellam. I *didn't* suggest it could *connect* to a floppy drive; I think there may have been a supplementary floppy disk containing (at least) a formatter, since those are the *only* strings in the ROM. It looks like it's just boot/driver code, so I think there must be some other way to format the (winchester) drive. I know you have a lot of Apple ][ stuff. Anything like this? Do you have a pinout for any contemporary Apple ][ SASI/SCSI interface? -- Pete Peter Turnbull Dept. of Computer Science University of York

26 years, 8 months

Ancient disk controllers

by ethan_dicks＠yahoo.com

--- Richard Erlacher <edick(a)idcomm.com> wrote: > see below, please. > > Dick > > -----Original Message----- > From: Ethan Dicks <ethan_dicks(a)yahoo.com> > >> 20MHz/4 = 5MHz = standard ST506 data rate. > > > >Right. It's the right rate for an 8" disk. > > > Nope, it's not! the right rate for 8" Winchesters is 4.34 MHz! Damn! Typo. I *know* that the 8" disk transfer rate is below 5Mhz. The recent coverage of the WD-1001's were quite explicit in that regard. -ethan _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com

26 years, 8 months

OT Was z80 timing... 6502 timing

by jax＠tvec.net

>Ooh! A machine code competition. I'm in! I'll do the 6502 and whoop >EVERYONE'S ass! > Wait just a minute..... Since we have been discussing various "ethnic" pronunciations, I am compelled to point out that this statement may be interpeted differently than intended. As a born\bred survivor of the land of redneck, pickup truck, and chewing tobacco, I assert that a "whoop" is a loud yelling type of activity. The execution of which on someone's posterior will bring a certain confusion to your enemy ( he will think you are a fruit ), but will not render him defeated. I laughed so hard at this mental image it made me hurt. :) Try "whup" next time, as in "opening a can of whup-ass". My 2 centavos from the Republic of Texas. BTW, my money's on Tony. jax(a)tvec.net

26 years, 8 months

z80 timing... 6502 timing

by edick＠idcomm.com

Kindly give the comments interleaved with your quoted message below a look. Dick -----Original Message----- From: Sellam Ismail <dastar(a)ncal.verio.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Saturday, April 17, 1999 2:45 AM Subject: Re: z80 timing... 6502 timing >On Sat, 17 Apr 1999, Mike Ford wrote: > >> >Ooh! A machine code competition. I'm in! I'll do the 6502 and whoop >> >EVERYONE'S ass! > Rules are a problem, aren't they? > >> And then you woke up. First what are the rules, 6502 or 65C02, code in Rom >> or Ram, what is the code supposed to do? > Well . . . There's the problem . . . first of all, the code's got to be executable on something everyone has got available, or it's got to be simulated on a simulator everyone has available, else there'll be a limit on interest right away . . . Then, shouldn't there be some consideration of the coding/debugging time involved? I'd lean in favor of a PC-compatible simulator. That makes the computation of actual execution time straightforward. . . and, of course, it's got to run the code on a "real" processor, not just a putative "we could build . . ." sort of thing, right? . . . well, maybe . . . Then there's the question about WHICH 6502 to use. Given a listing, it's easy enough to compute how long it takes the code to run, but which instruction set? What about undocumented features? Both these processors were famous for those. Of course, there doesn't have to be a limitation, i.e. one could consider ALL available cores. I'd propose it be a significant problem, but one which is well-defined, i.e. algorithms are published, hence the problem solution is well-defined, and I'd propose further that the same algorithm be used so we compare "apples with apples." As for the processor core, well, it's also got to be one everybody's got available, yet it wants to be one which WAS available in 1982. That might include the Synertek, MOS, and MAYBE the Rockwell core. We can't just say 65C02, because it was buillt in several conflicting versions. What about the Z-80 core? Whose? Which one? Speed, of course, should be "limited" to whatever was available in 1982. That certainly includes the Synertek (MOS Technology-comptible)"4MHz" 6502C (always worked fine at 5 MHz by then), as well as the Zilog Z-80B (6-MHz). Was the 8MHz part out in 1982? > >> My vote goes for something with some graphical element so we can "see" what >> is happening. (spinning ball, etc.) Whereas this might be "cute" it is very limiting, in that it has to be a graphics-capable environment available with both processors. It should not "fall" conveniently for either processor, so the graphics array should be large, and, AFAIK there's no such system for either processor. What should be done, here? Should we build a board? How do we measure how fast it's going? Remember, the hardware environment has to be more or less the same for both processors. >BRING IT ON, MO FO! > >Sellam Alternate e-mail: dastar(a)siconic.com >--------------------------------------------------------------------------- --- >Don't rub the lamp if you don't want the genie to come out. > > Coming this October 2-3: Vintage Computer Festival 3.0! > See http://www.vintage.org/vcf for details! > [Last web site update: 04/03/99] >

26 years, 8 months

Ancient disk controllers

by edick＠idcomm.com

see below, please. Dick -----Original Message----- From: Ethan Dicks <ethan_dicks(a)yahoo.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Saturday, April 17, 1999 8:17 PM Subject: Re: Ancient disk controllers > > >--- Tony Duell <ard(a)p850ug1.demon.co.uk> wrote: > >> > The final connector, J6 is 50 pins. >> > >> Which pins are used on the 50 pin connector? Could it be pinned out as a >> SCSI port. Or is it possibly some custom host interface? > >It could be a custom host interface. Among other anomalies, I don't see >any terminating resistors. > >> For example I >> have here the data sheet for the WD1001 controller. It uses essentially >> the chipset you mentioned. It has a 50 pin host connector, but it sure >> ain't SCSI. > >Can you scan that data sheet or send me a photocopy? I'd pay for >copying/mailing. > >> 20MHz/4 = 5MHz = standard ST506 data rate. > >Right. It's the right rate for an 8" disk. Nope, it's not! the right rate for 8" Winchesters is 4.34 MHz! >> 8MHz is a common enough clock for the 8x300 series of CPUs as well. That's true enough. >OK. > >> What bothers me, if this _is_ a SCSI controller is that there seems to be >> no way of setting the device address. > >No place that I can see. > >> My guess is that it's a sort-of WD1001 clone. It predated the WD1001 by some time. >OK. That makes sense. In fact, when I read the recent debates of >WD1001's, I thought of this board. I didn't think I could find it >as fast as I did. It could have been packed a lot deeper than it >was. > >Thanks for the insights. > >-ethan > >_________________________________________________________ >Do You Yahoo!? >Get your free @yahoo.com address at http://mail.yahoo.com >

26 years, 8 months

Bad form...

by mbg＠world.std.com

... to follow up to one's own posts, but I've done a little more research and I suspect that the Megalink boards are some sort of network board. I had originally been informed that they were some sort of video capture board... Anyway, now all I need to do is get some programming info about them. Megan Gentry Former RT-11 Developer +--------------------------------+-------------------------------------+ | Megan Gentry, EMT/B, PP-ASEL | Internet (work): gentry!zk3.dec.com | | Unix Support Engineering Group | (home): mbg!world.std.com | | Compaq Computer Corporation | addresses need '@' in place of '!' | | 110 Spitbrook Rd. ZK03-2/T43 | URL: http://world.std.com/~mbg/ | | Nashua, NH 03062 | "pdp-11 programmer - some assembler | | (603) 884 1055 | required." - mbg | +--------------------------------+-------------------------------------+

26 years, 8 months

How to read recalcitrant floppies?

by marvin＠rain.org

Ethan Dicks wrote: > > I am attempting to back up some floppies from a project I did a few years ago. > The sets of 3.5" 1.44Mb IBM floppies have been stored in a box, in a cool and > dry room. Out of one set of 12 and one set of 15 disks, I have four disks > that have read errors that DOS won't get past, bad sectors and the like. One program I have used with a great deal of success is Spinrite.

26 years, 8 months

Another identification needed...

by mbg＠world.std.com

I have a few more boards which need identification. Again, the scans can be found at ftp://ftp.std.com/ftp/pub/mbg/scans/computrol_30-0096_7.jpg it is a two-board set. There is an over-the-top connecting cable and a thin cable with a bnc connector on the end. One board is labelled 'Memory Map Megalink 1' and 'dma bus' and the other is labelled 'Memory Map Megalink 2' and 'datacom'. They're qbus boards, but with no switches for setting addresses and/or vectors. Can anyone identify the pair of boards? Thanks in advance... Megan Gentry Former RT-11 Developer +--------------------------------+-------------------------------------+ | Megan Gentry, EMT/B, PP-ASEL | Internet (work): gentry!zk3.dec.com | | Unix Support Engineering Group | (home): mbg!world.std.com | | Compaq Computer Corporation | addresses need '@' in place of '!' | | 110 Spitbrook Rd. ZK03-2/T43 | URL: http://world.std.com/~mbg/ | | Nashua, NH 03062 | "pdp-11 programmer - some assembler | | (603) 884 1055 | required." - mbg | +--------------------------------+-------------------------------------+

26 years, 8 months

Ancient disk controllers

by edick＠idcomm.com

My understanding prior to buying these controllers was that they were incompatible with the WD1000 and 1001 series, and were not SASI or SCSI either, thought they purportedly had a similar handshake. Beyond that, I need to find and subsequently read the documents. Dick -----Original Message----- From: Eric Smith <eric(a)brouhaha.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Saturday, April 17, 1999 7:28 PM Subject: Re: Ancient disk controllers >> include a N8X305N processor, some N82S181N ROMs, an N8X371N with leads going >> right to the 50-pin connector, and five socketed WDC parts copyrighted in 1980: >> WD1100V-03, WD1100V-01, WD1100V-04, WD1100V-05 and WD1100V-12. There is a >... >> As I said, I was told when I bought it that it was a SCSI controller. I >> remember trying to use it some years ago and not having much success. Does >> anyone have any info on this oddball? > >Sounds like a clone of the WD1000 or WD1001, which are nowhere close to >either SASI or SCSI.

26 years, 8 months

z80 timing... 6502 timing

by allisonp＠world.std.com

<Western Digital disk controllers are a little harder to get, so I'd <change it to 'a disk controller of your choice' which means you can use <an 8272 or whatever (trivial to get off an old PC card). 1793s are common enough and cheap too. If I went with the 765 (8272) I have to claim unfair advantage! <Considering you can make a serial port in a couple of chips, this is not <a major design task.... But it's overhead is trivial and well enough understood as to mean little. IT would be more of a challenge if each person supporting a processor had to use a different one. That would be a true learning experience. As to hardware... I cheat. I have SBCs for most common cpus. 1976 imp48 8048 (cute little sbc with tape IO, TTY, relays) 1977 8048 from byte 8048 (this was an 8035 with a mini front pannel) 1980 8051 8751 (basically a 8051 SBC with monitor) 1978 SC/mp ISP8A500 (sc/mp I) 1979 National TBX 8073 (SC/MP II with tiny basic) 1977 COSMAC ELF base 1802 (quest board) 1976 6800d1 6800 1977 kim1 6502 1983 Telvideo 905 R65c02 (card from terminal, good as SBC!) 1978 8x300 proto 8x300 (signetics) 1981 SDK78 7800 (nec propritary) 1981 78pg11 Protoboard 78pg11 (NEC propritary) 1979 Tk80 8080 1980 explorer8085 8085 (base card has 8085, ram and rom) 1980 Computime CPUZ z80 (s100 card with 1k ram, serial, eprom z80) 1981 Vt180 Z80 (z80, 64k, 4 serial, FDC, Eprom, RTC) 1981 Hurikon MLZ92 Z80 (Z80, mmu, 64k ram, eprom, serial,FDC) 1978 INtersil sampler (6100, 256w ram, rom, serial) 1982 29116 proto 29116/2911 proto for bitblitter 1982 Z8001 proto z8001 (z8001, 16k ram, 16k eprom, serial) 1982 Falcon T-11 (pdp11 chip, ram, parallel, serial, rom) 1979 SSS technico TI9900 (9900, ram, rom, serial) 1986 Advice 78032 (uVAXII, serial, 96k ram, 512k rom) The advice was used in 87 to assist the MV2000 design! All are classics, only the Advice wasn't available in '83. Now if I wanted to get exotic, I have a load of 2901/2911s with date codes pre 1980. Also 29116s (pre 83). Also enough raw 8748/9 and 8751 parts to do a major hack (maybe 50 or 60 of each). the 8749s are the slower 1982 parts that only run at 11mhz (instruction cycle time of 1.36uS) However with the prior to 1982 limit sthere are no sortage of choices. I'm not above using multiple cpus to do the task or mixing several different ones. Allison

26 years, 8 months

OT Was z80 timing... 6502 timing

by allisonp＠world.std.com

<In a _programming_ contest? Surely you jest... (or rather, don't waste <your hypothetical money)... < <Although, if I'm allowed to use _any_ processor, including one I've <designed myself, then things might get mildly more interesting... Oh, I could do that. My spin would be a PDP-8 with hardware of my own making. At one time I had static ram card in an 8e with hacked cpu timing (1uS cycle without trying hard). Then again the list of CPUs I have programmed on is long enough to know which ones to pick for what. Allison

26 years, 8 months

OT: K&R vs. ANSI C (was: Re: Abort, Retry, Ignore, Fail?...)

by yakowenk＠cs.unc.edu

Actually, yes, I presently maintain (and develop) code for a living.

26 years, 8 months

shipping floppy disk drives

by SUPRDAVE＠aol.com

In a message dated 99-04-17 22:35:42 EDT, you write: > I'll be shipping a few floppy disk drives soon, and want to minimize > the shipping damage to them. So, is it better to ship them with the > drive door open or closed? And with or without a floppy inserted? ive always shipped drives with a floppy inserted if i dont have the original cardboard/plastic shipping disk. since the heads are clamped down on the disk, supposedly that would minimize damage from movement or rough handling by idiot delivery companies that never treat anything with care.

26 years, 8 months

Signal detection

by yakowenk＠cs.unc.edu

On 16 Apr 1999, Cameron Kaiser <ckaiser(a)oa.ptloma.edu> wrote: ] ... ] ::Could anyone tell me how a radio detects signals vs. static? There is a ] ... ] Probably signal strength. Undoubtedly really loud static would trip it also ] but your garden-variety radio static just isn't that loud. It's a shame that wouldn't work on a mailing list. Getting lots of noise lately. :-/ Bill.

26 years, 8 months

OT: City Names

by yakowenk＠cs.unc.edu

On 16 Apr 1999, Philip.Belben(a)pgen.com wrote: ] (I have somewhere a Yugoslavian banknote. Everything is written on it in four ] local languages - two using Cyrillic and two using Latin characters. The ] languages are similar enough that AFAIK nothing needs to be said more than ] three times...) Take a look an Indian rupee sometime. Each note is printed in eleven languages, each with its own script. (Though to me, two or three look pretty darn similar to Hindi.) To try and drag this back to a somewhat related topic, we often hear about computers from North America, Europe, Russia, and Australia. But is anyone here collecting machines from any more "exotic" places? Are there any cool classic machines indiginous to any country from the Middle East, Africa, South America, or South or East Asia? It would be nifty to compare architectures that were not just clones or incremental improvements of machines we already know about. Heck, I know Japan produced a lot of their own computers. Were they all clones of machines we know (or vice-versa)? Bill.

26 years, 8 months

z80 timing... 6502 timing

by ethan_dicks＠yahoo.com

--- Tony Duell <ard(a)p850ug1.demon.co.uk> wrote: > > Ok, the environment is any home micro from the 70s or 80s that ran on any > > processor. The more rudimentary the processor, the more points you get. > > I choose the 4004. > > You have a _home micro_ based on a 4004? What the heck is it? I always wanted to implement a binary clock on the 4004. I never got around to it. Has anyone written a 4004 simulator in some flavor of C? (I recall a recent announcement about a simulator in a language other than one that I use on a regular basis). -ethan -ethan _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com

26 years, 8 months

Ancient disk controllers

by ethan_dicks＠yahoo.com

The recent postings regarding old disk controllers has caused me to dig out one I got at Dayton many years ago. I bought it for the external box, something I didn't have at the time... it appears to be a SCSI card, but might be a SASI card. It was made by Davong Systems, Inc., a company I remember from my younger days. The copyright is 1982, but there are chips on it from 1983. On the back are numbers like 0034 REV (J1) K 310026 170. The J1 is scratched out and the K handwritten. The 170 is also handwritten. On the long end in copper is the number 11-000034 REV E. Connector J2 and J1 are together on one side of the long end (J1 is 34-pins with half of them grounds, J2 is 20 pins with pins 2, 4, 6, 8, 12, 16 and 20 grounded). J3, J4 and J5 are in line on a short end, 20 pins each, similar ground pattern to J2. J2 through J5 appear to have connections to a Motorola AM26LS32 and a TI AM26LS31 which I take to be some sort of analog chip. The final connector, J6 is 50 pins. J1 appears to be the control cable for an ST506 drive, J2-J5 appear to be data cables for talking to four drives. The interesting chips on the board include a N8X305N processor, some N82S181N ROMs, an N8X371N with leads going right to the 50-pin connector, and five socketed WDC parts copyrighted in 1980: WD1100V-03, WD1100V-01, WD1100V-04, WD1100V-05 and WD1100V-12. There is a crystal at 20Mhz in the analog section of the board and an 8Mhz crystal by the processor. In the middle of the board are three vias that are labelled as if they are configuration pads, in an inverted-L, labelled "1", "2" and "3", with a "W" above them, As I said, I was told when I bought it that it was a SCSI controller. I remember trying to use it some years ago and not having much success. Does anyone have any info on this oddball? Thanks, -ethan _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com

26 years, 8 months

z80 timing... 6502 timing

by edick＠idcomm.com

I don't really care what's done here, but I thought the object was to see which of the two processors in the "subject" field would make for faster execution of a useful and published algorithm than the other. It's necessary that the algorithm be implementable on similarly equipped platforms, whether they exist physically or not. The limitation is that it must be timed as executed on a device from one of the two processor types in question, and physically available in 1982-83 as that's the time-frame about which the discussion preceding this coding exercise was centered. There's no point in specifying it for an Apple-II, because that one didn't even run the processor at the current maximum rate due to its overlap with video display refresh timing, and because it would involve too much unrelated design and construction effort to come up with a suitable substitute implemented using a Z-80. Consequently I proposed one wire his own computer using the processor, 64K of static ram, and a serial port of some type TBD. Maybe, just for the exercise, a file device, e.g. a floppy disk controller ala WD1770/72 ought to be included. That's got to be hashed out for sure, if it's to be realized in hardware. Problems potentially lie in the path, however, as some of the hardware may be scarce if availalble at all. A suitable port for attaching a terminal or PC ought to be included, but only in its most basic form. That way, when the builder is finished, he has an item he could possibly use for something, should he choose to do so. This can all get to be a mite burdensome when all you wanted was to see what the fastest or most efficient code one could come up with would look like, which I why I suggested a simulator. The only problem with that is that one could then write and assemble code which didn't in reality do what it claimed because the I/O wasn't simulated as well. This requires some more thought. Dick -----Original Message----- From: Sellam Ismail <dastar(a)ncal.verio.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Saturday, April 17, 1999 2:22 PM Subject: Re: z80 timing... 6502 timing >On Sat, 17 Apr 1999, Richard Erlacher wrote: > >> Well . . . There's the problem . . . first of all, the code's got to be >> executable on something everyone has got available, or it's got to be >> simulated on a simulator everyone has available, else there'll be a limit on >> interest right away . . . Then, shouldn't there be some consideration of >> the coding/debugging time involved? I'd lean in favor of a PC-compatible >> simulator. That makes the computation of actual execution time >> straightforward. . . > >Not necessarily. You measure the code based on an analysis of the clock >ticks it uses. This way the competition is platform independent. Of >course a suitably platform independent code spec would need to be >developed. > >> . Then there's the question about WHICH 6502 to use. Given a listing, it's >> easy enough to compute how long it takes the code to run, but which >> instruction set? What about undocumented features? Both these processors >> were famous for those. Of course, there doesn't have to be a limitation, >> i.e. one could consider ALL available cores. > >This would not be limited to the 6502. The idea is to see who can come up >with the most efficient algorithm on any processor. > >Sellam Alternate e-mail: dastar(a)siconic.com >--------------------------------------------------------------------------- --- >Don't rub the lamp if you don't want the genie to come out. > > Coming this October 2-3: Vintage Computer Festival 3.0! > See http://www.vintage.org/vcf for details! > [Last web site update: 04/03/99] >

26 years, 8 months

Ancient disk controllers

by edick＠idcomm.com

I've got one or two of these DAVONG controllers, as well as some of the documentation. I bought them as spare parts for the Western Digital controllers I liked better. Since they had the 8X305 and the requisite current injection valve transistor (don't ask me about that!. . . it's characteristic of I2L logic, I'm told.) and similar varistors, I thought the couple of bucks for the controllers was worth it. I bought the boxes and supplies for useful applications, though the boxes were odd enough never to find them. If you have questions, I may be able to help, but I've never read the doc on these so be patient. Dick -----Original Message----- From: Ethan Dicks <ethan_dicks(a)yahoo.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Saturday, April 17, 1999 6:18 PM Subject: Ancient disk controllers > >The recent postings regarding old disk controllers has caused me to dig out >one I got at Dayton many years ago. I bought it for the external box, >something I didn't have at the time... it appears to be a SCSI card, but >might be a SASI card. > >It was made by Davong Systems, Inc., a company I remember from my younger >days. The copyright is 1982, but there are chips on it from 1983. On the >back are numbers like 0034 REV (J1) K 310026 170. The J1 is scratched out >and the K handwritten. The 170 is also handwritten. On the long end in >copper is the number 11-000034 REV E. > >Connector J2 and J1 are together on one side of the long end (J1 is 34-pins >with half of them grounds, J2 is 20 pins with pins 2, 4, 6, 8, 12, 16 and 20 >grounded). J3, J4 and J5 are in line on a short end, 20 pins each, similar >ground pattern to J2. J2 through J5 appear to have connections to a Motorola >AM26LS32 and a TI AM26LS31 which I take to be some sort of analog chip. >The final connector, J6 is 50 pins. > >J1 appears to be the control cable for an ST506 drive, J2-J5 appear to be >data cables for talking to four drives. The interesting chips on the board >include a N8X305N processor, some N82S181N ROMs, an N8X371N with leads going >right to the 50-pin connector, and five socketed WDC parts copyrighted in 1980: >WD1100V-03, WD1100V-01, WD1100V-04, WD1100V-05 and WD1100V-12. There is a >crystal at 20Mhz in the analog section of the board and an 8Mhz crystal by >the processor. In the middle of the board are three vias that are labelled >as if they are configuration pads, in an inverted-L, labelled "1", "2" and >"3", with a "W" above them, > >As I said, I was told when I bought it that it was a SCSI controller. I >remember trying to use it some years ago and not having much success. Does >anyone have any info on this oddball? > >Thanks, > >-ethan > >_________________________________________________________ >Do You Yahoo!? >Get your free @yahoo.com address at http://mail.yahoo.com >

26 years, 8 months

z80 timing... 6502 timing

by allisonp＠world.std.com

<65C02, because it was buillt in several conflicting versions. What about <the Z-80 core? Whose? Which one? Speed, of course, should be "limited" t <whatever was available in 1982. That certainly includes the Synertek (MOS In 1982 all of the z80s in the market had the same hidden features including the IX/IY 8bit ops. I know of no z80 that didn't have them. Not all of them were available to the 6mhz spec though many could be pushed. Also allowed is the 8085 (available as a 5-6mhz part then). Again all of the 8085s had the extra unsupported instructions as they were deem important! Allison

26 years, 8 months

How to read recalcitrant floppies?

by jhfine＠idirect.com

aaaaa >Ethan Dicks wrote: > I am attempting to back up some floppies from a project I did a few years ago. > The sets of 3.5" 1.44Mb IBM floppies have been stored in a box, in a cool and > dry room. Out of one set of 12 and one set of 15 disks, I have four disks > that have read errors that DOS won't get past, bad sectors and the like. Jerome Fine replies: You don't mention if the bad sectors are in the data or the file structure. Also, if in the data, would a partial recovery of the file be acceptable? Also, out of 2880 blocks for each 3.5" 1.44 MByte floppy, about how many sectors (blocks) are bad? While I can't help much with hardware recovery techniques, I can guarantee that you can use RT-11 to at least write (copy) each diskette onto a second copy with only the bad sectors not copied across. If all the bad sectors are in the data files, you will at least recover as much of the file as possible. Sometimes in RT-11, blocks that are mostly bad can be encouraged to be duplicated by repeated attempts. The copy utilities (PIP or DUP) have a switch to repeat the read until it completely fails OR to IGNORE failures and continue. I don't remember if a DEVICE copy has that feature, but if you say you are willing to try RT-11, I can help guide you through the process. What OS on what hardware will you read the 3.5" floppy. If it is a PC under W95 (I use it only to do e-mail - not by choice), there are very good tools to help. Sincerely yours, Jerome Fine RT-11/TSX-PLUS User/Addict

26 years, 8 months

z80 timing... 6502 timing

by edick＠idcomm.com

This must be something different from what we had at the beginning, as the constraints were for production processors commercially available in 1982-1983 and in either the Z-80 or 6502 architecture families. The reason for this is obvious. It has got to be possible to run the code in a real device in the "here and now" timeframe. Otherwise one could simply say well, "I wrote this code for the XYZ at 24.576 GHz and the whole program requires only one instruction." Further constraint should be that the author must own a running system capable of running the subject software on it in the native processor. This system must consist of components commercially available during or before the subject time period, i.e. 1983. Thirdly, it should be proven by replication (successful execution of the submitted code set on another computer not necessarily owned by the author of the submitted software) that this fete is achievable with the code set submitted. A simulator or even some fancier assemblers can be used to indicate the execution time. It's not desirable to include processors which don't exist yet in any comparison purported to be a timing comparison between Z-80 and 6502. That doesn't mean you can't look at whatever else someone might submit for general inspection and interest, but we do want to have a well-defined goal. -----Original Message----- From: Sellam Ismail <dastar(a)ncal.verio.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Saturday, April 17, 1999 5:27 PM Subject: Re: z80 timing... 6502 timing >On Sat, 17 Apr 1999, Tony Duell wrote: > >> > Contest open for any CPU anyone would care to write code for. >> >> Including one that I've designed? In which case, how general-purpose does >> it have to be? I have half an idea to make a state machine that does >> binary -> roman conversions, but not anything else. I suspect I could get >> it rather fast, though. > >Sure, why not! That would be great. > >> (Yes, that's cheating. I know it's cheating. But it's not specifically >> disallowed by the above). > >I don't think anyone should have to be handicapped. Of course, you'll >have to demonstrate that it actually work, although I have no doubt you >can and will :) > >Sellam Alternate e-mail: dastar(a)siconic.com >--------------------------------------------------------------------------- --- >Don't rub the lamp if you don't want the genie to come out. > > Coming this October 2-3: Vintage Computer Festival 3.0! > See http://www.vintage.org/vcf for details! > [Last web site update: 04/03/99] >

26 years, 8 months

Dumb OS question

by jolminkh＠nsw.bigpond.net.au

I recently found an ancient copy of QNX, which seems to be a light unix like OS. Looking on the WEB, I found that current versions are still around, but marketed as a "Real Time" OS. The 80's documentation I have says nothing about real time. My dumb question: What is a real time operating system? Hans Olminkhof

26 years, 8 months

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