test-drb

test-drb@ccmp.vtda.org

101090 discussions

by ethan_dicks＠yahoo.com

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. I know that circa 1993, these disks were good. They were written once, mailed to me, loaded once and put away. I would like to preserve the data because it has some small historic significance. It's not earth-shattering if the data is gone forever, but those of us who play adventure games would lose a little link to the past. I do not belive that the client still has copies of this original data, so that's not an option. The project eventually made it to market, so it's not a "lost" game or anything; but these disks do represent a work in progress with some interesting bugs. Are there any tools to go divining on DOS floppies that work better than an endless succession of "R"etries? It's an all or nothing prospect; the first disk has the install file, the remaning disks have a chopped monolithic data file. If one disk can't be read, the whole set is fundamentally useless. Thanks for any suggestions. -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

As I recall, all the undocumented operations have the two ls bits set. Is that correct? Maybe I should add them to my assembler/debugger. The one I routinely hear about the Z-80 is one which places the odd parity of the bytes (or maybe the lsb's of the bytes) in a block moved with an LDIR or INIR instruction into the carry or some such. This instruction is supposed to leave carry unaffected, but doesn't. Dick -----Original Message----- From: Hans Franke <Hans.Franke(a)mch20.sbs.de> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Saturday, April 17, 1999 10:15 AM Subject: Re: z80 timing... 6502 timing >> Were you aware of the neat little opcodes that were built into the 6502? I >> don't have my list of them any more, but back in the KIM days, there were >> several lists in circulation. As I recall, one of them was a double load, >> i.e it loaded a value into both a register and the accumulator. I believe >> another loaded a register and pushed the value on the stack at the same >> time. Esoteric, for sure, but you never know . . . > >Like SHIFT&OR (0F,1F,1B,...), ROL&AND (2F,3F,3B,...), LSR&XOR ($F,5F,5B,...), >ROR&ADD (6F,7F,7B,...) etc ... most are realy exotic and save only a second >instruction, but some could have been a big help, if they had been official >(like AND A,X and STORE, without changing A or X - saving up to 4 instructions, >or LOAD A&X, or AND MEM&X/MEM&Y). Some are more or less useles, like the STOP >(halts execution, only reset will wake up the CPU) or just longer NOPs (two and >tree cycles). > >THe 65xx stuff is quite known, but what has been new to my ears are the >8085 'hidden' operations. > >Gruss >H. > >-- >Stimm gegen SPAM: http://www.politik-digital.de/spam/de/ >Vote against SPAM: http://www.politik-digital.de/spam/en/ >Votez contre le SPAM: http://www.politik-digital.de/spam/fr/ >Ich denke, also bin ich, also gut >HRK

26 years, 8 months

Apple HAL XEBEC controller

by edick＠idcomm.com

Xebec made a number of "specialized" bridge controllers, which fit between the host adapter, which is what you've described, in this case possibly intended to go to a compatible version of their 14xx-series controllers which, in turn, provides a SCSI interface to an ST506 drive, which you apparently have on hand. It is likely that the 26-pin connector is to the Apple II version of SCSI which was put out back then on a 25-pin DB-25 connector. I recently got a drive with a Xebec label on its enclosure, having bought it for the enclosure, and found the drive had an integrated adapter on it which was terninated in a DC-37 connector, not unlike what was on the early Bernoulli Boxes from IOMEGA. I didn't investigate the pinout or anything, naturally, since I don't care about small drives like this. There's probably a similar version for this card's interface as well. Dick -----Original Message----- From: Pete Turnbull <pete(a)dunnington.u-net.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Saturday, April 17, 1999 9:45 AM Subject: Apple HAL XEBEC controller >One of today's acquisitions is a small card for an Apple ][ (or Apple ///), >labelled "APPLE 2/3 XEBEC INTERFACE REV 1". > >I happen to have a couple of old Xebec ST412 winchester controllers, so I'd >like to try this out. > >Can anyone tell me the pinout of the 26-pin header at the end of the card? > Pins 3,7,11,15,17,19,21,23,25 are grounded, the other seventeen seem to be >signal lines. Pins 1,5,9,13,20 are high impedance; the other even-numbered >pins are terminated by a 220/330R resistor pack. > >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. > >-- > >Pete Peter Turnbull > Dept. of Computer Science > University of York

26 years, 8 months

Several things

by yakowenk＠cs.unc.edu

On 9 Apr 1999, ard(a)p850ug1.demon.co.uk (Tony Duell) wrote: ... ] A ROM _is_ combinatorial logic. I don't want to get into a silly argument ] over this, but I have great difficulty finding a conceptual difference ] between a combinatorial circuit built from a pile of AND, OR and NOT ] gates and the same circuit built (albeit using a lot more transistors) in ] a ROM. To claim that a CPU using a ROM is microcoded but one with ] _identical_ internal states using simple gates as the feedback logic ] round the sequencer flip-flops is not is a very strange way of thinking ] about things. Request accepted; silly argument follows. (Oh, you said "don't"? Oh well, too late.) Do you mean to say that _all_ computers are microcoded? After all, the control logic can always be modelled by some number of state FFs and a large-enough ROM, couldn't it? Or is your claim that there is no such thing as microcoding? That strikes me as far-fetched as well. The difference is that a ROM is easily replaceable; slap in another ROM or EPROM with different microcode burned in, and you've got an entirely different machine on your hands. Maybe to you it is just as easy to redesign some section of the circuit board, etch a new one, pull the newly required chips from your very-deep storage bin, and Bingo! you're done. For most of us, I suspect that sounds like quite a lot of effort. I don't think anybody ever claimed that microcoded machines could do things that non-microcoded machine could not, or vice-versa. It is a matter of convenience. And maybe there is some added comfort level for software geeks, using a (micro)program to control everything, and being able to alter it just like any other software (or firmware). I guess it is exactly the added (and admittedly wasted in any fixed design) transistors, just sitting there unused, waiting to be assigned work, that makes microcoding attractive - it is easier to adjust precisely because you don't have to muck around with how many transistors are in there, or worry about board-space/power-consumption/fanout/etc/etc that you might have to worry about if you wanted to adjust some hard- wired discrete logic. Bill. (Gee, that didn't turn out to be nearly as silly as I had expected.)

26 years, 8 months

Signal detection

by max82＠surfree.com

Hi, Could anyone tell me how a radio detects signals vs. static? There is a little gauge on my radio that moves depending on the amount of noise vs. signal. I would guess that the digitally tuned radios that skip over the frequencies that are pure static work in the same way. What is this way? --Max Eskin (max82(a)surfree.com) http://scivault.hypermart.net: Ignorance is Impotence - Knowledge is Power

26 years, 8 months

z80 timing... 6502 timing

by edick＠idcomm.com

Were you aware of the neat little opcodes that were built into the 6502? I don't have my list of them any more, but back in the KIM days, there were several lists in circulation. As I recall, one of them was a double load, i.e it loaded a value into both a register and the accumulator. I believe another loaded a register and pushed the value on the stack at the same time. Esoteric, for sure, but you never know . . . Dick -----Original Message----- From: Hans Franke <Hans.Franke(a)mch20.sbs.de> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Saturday, April 17, 1999 9:27 AM Subject: Re: z80 timing... 6502 timing >> <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! > >a) The speed (of a particular CPU) used is not important for this, since >(I assume) we all can handle the transformation - the goal is still the >factor to use to judge the relative power. >b) unsupported OPCs in the 8085 ? Did I miss them ? I did 2 years of >8085 development projects, and never heared of (also of course never >used) - can you tell what they where alike ? > >Gruss >H. > >-- >Stimm gegen SPAM: http://www.politik-digital.de/spam/de/ >Vote against SPAM: http://www.politik-digital.de/spam/en/ >Votez contre le SPAM: http://www.politik-digital.de/spam/fr/ >Ich denke, also bin ich, also gut >HRK

26 years, 8 months

OT: City Names

by gareth.knight2＠which.net

William Donzelli >If people want to send _way_ off topic stuff to this list, my requests are >articles about ice fishing, reprints of old Home & Garden magazines, or >hardcore pornography. For the right price I can get you hardcore porn of women ice fishing with copies of Home & Garden. ;) -- Gareth Knight Amiga Interactive Guide | ICQ No. 24185856 http://welcome.to/aig | "Shine on your star"

26 years, 8 months

Power Frequency

by allisonp＠world.std.com

<I think you are spot on there, I am led to believe the 60hz decision in th <US and some other countries was made to facilitate the use of the <(relatively) precise mains frequency for clocks and other timing functions <This is also possible, even for motor driven clocks, with 50hz mains simpl <by careful motor design. Though it may have been less simple when the <decision was made. makes no difference save for one item... <equivalent to the mains frequency. This reduces/eliminates mains hum <strobing, though it is more of a historical problem with modern TV designs <think. No, more of a problem with OLD designs. The key item is that motors and transformers are physically smaller for same or similar VA capability with increasing frequency. there is a corner you turn as you go higher though as the iron in the course gets lossier and line radiation increses losses. So power distrubution has the 50/60 as a good bet. Note aircraft use 400nz for the compact transformers and reduced filtering in rectifiec circuits. There were also 25, 30 and 40hz systems. The NY subway at one time was 25Hz and the DEC mill prior to refurb in the 80s was 40hz (that power also lighted part of the town.) at one point in history. Allison

26 years, 8 months

Coding chanllange (was: z80 timing... 6502 timing)

by edick＠idcomm.com

It might, in fact, be interesting to see what limitations/enhancements the hardware features of the two processor types would impose. Interleaved display memory would effect both processors' ability to use memory, etc. I'd say it will difficult enough to come up with a problems suitable for a valid exercise without such difficulties. Dick -----Original Message----- From: Hans Franke <Hans.Franke(a)mch20.sbs.de> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Saturday, April 17, 1999 7:19 AM Subject: Coding chanllange (was: z80 timing... 6502 timing) >> > >Ooh! A machine code competition. I'm in! I'll do the 6502 and whoop >> > >EVERYONE'S ass! > >> > 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? > >Good point. > >> > My vote goes for something with some graphical element so we can "see" what >> > is happening. (spinning ball, etc.) > >Nice, but already to high level. >The task should be abstract enough to run within a simple >system, lets say a SBC system with CPU, some MEM and some >of the usual I/O&Controll stuff (Ports, Serial, Timer). > >Basicly there are two types of possible challanges: >a) implements some kind of standard code in a most speedy way, or >b) build some small, but sophisticated "real world" application. > >Challenge a) would meet the basic idea we had in our discusion: >define at what ratio two processors are equivalent when executing >a real task, while b) should be sophisticated enough to give a >'boh ey' (sound of exeptional admire) effect. > >In terms of a sportive competition a) would be a compulsatory >exercise, while b) is more a voluntary (free style) exercise. > >As I stated before, for our theme a) would be more aprobiate. > >As actual tasks I would suggest >for a): a 'simple' sorting challenge >given is >- Input media >- Input structure >- input data (same data or all participants, randomly generated) >- Type of sort algo to use (what about just a bubble ? :) >- Output structur >- Output media >the score schould be made up from >Execution time (mainly for the sort, but also for I/O) >Programm length (again most points to be given on the sort itself) >Style (readability, portability, maintainability) > >for b) a thing like a small multi tasking OS could be used, >maybe for a controlling application (heating or traffic - >or what about a model railroad setup ?) or other purposes ? >(This could be chalenging, since these kind of tasks are >maybe a bit tough for our little helpers :) > >So, you're opinion ? > >> BRING IT ON, MO FO! >> Don't rub the lamp if you don't want the genie to come out. > >MO FO ? I fear, I'll have to rub the lamp. > >Gruss >H. > >-- >Stimm gegen SPAM: http://www.politik-digital.de/spam/de/ >Vote against SPAM: http://www.politik-digital.de/spam/en/ >Votez contre le SPAM: http://www.politik-digital.de/spam/fr/ >Ich denke, also bin ich, also gut >HRK

26 years, 8 months

z80 timing... 6502 timing

by KFergason＠aol.com

> <> And then you woke up. First what are the rules, 6502 or 65C02, code in Ro > <> or Ram, what is the code supposed to do? > <> > <> My vote goes for something with some graphical element so we can "see" wh > <> is happening. (spinning ball, etc.) > My vote would be to implement an algorithm. Of course, which algorithm would a gruesome discussion. Kelly

26 years, 8 months

z80 timing... 6502 timing

by allisonp＠world.std.com

<> And then you woke up. First what are the rules, 6502 or 65C02, code in Ro <> or Ram, what is the code supposed to do? <> <> My vote goes for something with some graphical element so we can "see" wh <> is happening. (spinning ball, etc.) Grpahincs favor certain cpus but then we also ahve to specify the graphic interface as it may penelize some due to interface. Personally graphics are an issue unto themselves and seperate A possible list of micros for that era, I used 1982 as a cutoff date: 8bitters: 6502 z80 8080 8085 2650 1802 SC/MP 6800 (01/02/03, 6803) 6809 8048 8049 8051 z8 uPD 7800 (7800, 7811) 16bit or larger: TI9900 808x 6800x 16032 z8000 T-11 (PDP-11 in a 40 pin dip and not the F11.) 1600 9440 uFlame Pace/8900 No doubt I've missed a few. Let the war begin. Allison

26 years, 8 months

AMPRO LITTLE BOARD, etc.

by allisonp＠world.std.com

<Golly! I wasn't aware that they actually put a SCSI controller on the <board. That must have been several rev's later than mine. My two boards Next rev. Also Ampro was one of the guns in setting the base SCSI spec around 85ish. <were the beta and first release. I put a couple of hundred of these into <the field because I liked them and they allowed pretty compact packaging. Not hard to understand. <I was propping the door to a room in the basement with a couple of 10MB <RODIME 3.5" drives which might work really well with this arrangement. I <once ran one of these with a 1"-high 3.5"Sony drive which a PC believed wa <a 1.2MB drive. Maybe I can fool the FDC drivers into doing a similar thing <That would be handy. There's no "standard" 3.5" driver for CP/M. I have 3.5" miniscribe 20mb MFM hooked to a xybec scsi bridge on a SB180(also has 5380). Looks silly since the scsi bridge is larger than the drive and the SB180s. It works because the drive is faster seek than most older mfm drives like the st225 or 251. That and it throws less heat. <>Here we go again... I DIDN'T SAY IT WAS IDE. I said it was similar in <>respect that it was a bus level interface for a controller and predates < < <No, you surely didn't say that! It doesn't use the same cable definition o <any thing like it. It just happens to use a 40-conductor cable. The reaso Doesnt saying "its not IDE" cover that? I wes refering to the idea that the bus can be a base micro IO bus (read, write, address, data, reset, misc). That at the CONCEPT level is similar to IDE. <I said I'd try modifying the firmware to talk to an IDE drive is that ther <is reason to believe that the command structure is identical although the <hardware would have to be modified to load the registers as it's done on th <16-bit -WAH controller. The fact is that the 1000-05 and the 1002-05 bridg <controller boards use the same chip (WD1010-05) as the HDD interface. <That's where the command registers are located and they'll require <programming in the same way. Since the IDE drive has, essentially, the sam <register set on it to accomplish the controller functions, and the registe <set mapped in the same way as the WD1003-WAH, it should be possible to mak <it work similarly. No yes at the concept level. At the real level the IDE has 16 bit data path like the 1003, but the 1000-5 and 1002-5 tended to ahve differences that are quite distinct. I turned them up while doing an article for TCJ. That was about applying ISA-8 WD1002-WX cards as a cheap MFM host interface. I found the -HDO board had a different address and register layout. <>Finding them can be tough. the 6mhz are more common. 8530s or 8330s are <>easier to find and offer better perfomance. <> <I'm really not that hot for it, but think it would be charming to put a se <of '-H' parts in an early AMPRO Little Board and make it work at 8MHz. Th <timing should work with 100ns DRAMs. Aside from the PROM, I doubt anythin <other than the peripherals would be affected by the speed change. Of cours There were articles for upgrading the amproLB to 8mhz. See TCJ <www.psyber.com/~tcj>. <the FDC would require a different tap from the clock divider, but everythin <else should work as is, save, perhaps the PROM. The PROM might work if th <clock switch were hacked as well. (I believe there was a little sorcery <with switching the clock speed after copying the PROM into RAM, by switchin <the preset on a counter. What I liked about this was the really sensible Why not goo whole hog if your going to switch clock speeds and do clock stuttering. That way only certain parts or the processor cycle are stretched and the rest can run full bore. <packaging you could use with these small boards. I have a video <display/keyboard on a similar form factor which I'd really like to package <with these other two boards and the drives. That would be truly minimalis <for the time. I packed mine in a box I found at DEC (oddball) that was very compact. It also allows for external DC power (battery and solar) as mine has been modded to take mostly cmos parts (CPU, CTC, SIOs, EPROM, 53C80, and some of the losse ttl to 74hct). Power is way down. Allison

26 years, 8 months

8" drive on a pc controller

by allisonp＠world.std.com

<I wasn't aware that the NEC controller chip had a problem with the step <rate. I stuck with WDC FDC chips in my own applications. It was a problem of how the down counter for timing the steprate was designed. It had a granularity of 1 (8") or 2mS (5.25") and could truncate the first(only) step pulse. There were other paybacks that some designers really liked as the disk interface was more complete for things like head (side) selection, drive selection. When used with DMA it's a fairly sane chip to program. However the PC implmentation is rather badly hacked from the start and has become the defacto standard. If it were done as suggested ack then 8" drive would have been quite easy to do as well. Allison

26 years, 8 months

z80 timing... 6502 timing

by edick＠idcomm.com

Does the hardare need to be "real" or can it be simulated? That would make it less likely to favor one core over the other. If it's real, it has to be available to both processors and quite identical. Dick -----Original Message----- From: Mike Ford <mikeford(a)netwiz.net> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Saturday, April 17, 1999 2:26 AM Subject: Re: z80 timing... 6502 timing >>Ooh! A machine code competition. I'm in! I'll do the 6502 and whoop >>EVERYONE'S ass! > >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? > >My vote goes for something with some graphical element so we can "see" what >is happening. (spinning ball, etc.) > >

26 years, 8 months

How to read recalcitrant floppies?

by manney＠hmcltd.net

Well, there's Norton disk editor. I've rescued data with it before. It certainly is a time-intensive operation, though! I have a spare license I can loan you if you need one. P Manney manney(a)hmcltd.net Is it illegal to yell "Movie!" in a fire station? >> that have read errors that DOS won't get past, bad sectors and the like.

26 years, 8 months

Kaypro (fwd)

by siconic＠jasmine.psyber.com

Here is someone in Colorado with many nice Kaypro's they'd like to get rid of. Please reply to the SENDER of the message: Reply-to: DaveG56313(a)aol.com ---------- Forwarded message ---------- Date: Mon, 12 Apr 1999 19:43:42 EDT From: DaveG56313(a)aol.com Subject: Kaypro Are you interested in Kaypro hardware and software? I have four of them (I think it's four) gathering dust in a store room. One is my original Kaypro II with an internal Ramdrive I built from plans I found on GEnie. I think there's another original Kaypro II, a Kaypro IV, and two Kaypro 10's (one with two 20mb hard drives replacing the original 10mb drive. Four of the five are in working order. Software includes a complete shareware library from the local Kaypro Users Group I belonged to. There are also two daisy wheel printers--Diablo 620's. One is parallel; one is serial. Let me know if there is any interest. Dave Green Loveland, Colorado Sellam Alternate e-mail: dastar(a)verio.com ------------------------------------------------------------------------------- Puttin' the smack down on the man! Coming in 1999: Vintage Computer Festival 3.0! See http://www.vintage.org/vcf for details [Last web site update: 04/03/99]

26 years, 8 months

OT: City Names

by Philip.Belben＠pgen.com

>> > > Just back from Warschau (Poland) - Thanks. And BTW: since Karfreitag >> >> > Where? Oh, you mean Warszawa. Warsaw. ;-) >> >> (You're just lucky that's one of the few polish words without lots of >> accents etc.) Hmm do you want to start another War ? ;) >> >> If you live in a city like Munich you learn about the ways >> of naming a city - and of coure how senseless it is to >> belive in calling a thin worldwide with one single name. Hmm. I generally try and name a city in a language that is spoken in that city - so I am usually careful to write Muenchen, Nuernberg, Braunschweig for Munich, Nuremberg and Brunswick. But I admit that I would probably simply have written Warsaw for Warszawa. The main difficulty is when the language doesn't use Latin characters. I wouldn't even know how to write "Bangkok" in Thai, although I think I could manage "Taipei" in Chinese. (But Taiwanese place names should be transliterated according to the Wade-Giles system still used in Taiwan, rather than in PinYin as on the mainland) Polish is one of the less bad languages for accents - Czech is far worse, to the extent that in the UK we generally use Polish spellings... > Well, maybe you could explain it to me, I'm afraid I don't get it. :^) > I always wondered why Munich sometimes gets shown as Munchen. I can't do > those funny accented characters, (umlauts?) even if I knew what they meant, > just as well, most people around here have enough difficulty with 26 > letters. I don't know how you guys cope with all the extras, not to mention > all this masculine/feminine/neuter gender and case stuff. Confused the hell > out of me. Umlauts are reasonable enough. Gramatical gender is an anachronism that should be abolished as soon as possible. But English spellings (whenther British or American) have been in sore need of reform since before they were standardised... > Good things about living in a single island country that's larger than most > of Europe. > > 1) Everybody speaks English. ('Cepting a few migrants/boat people....:^) > They expose kids to other languages at school, but theres is no real > need/pressure to learn one to a level where conversation is possible. > (Who we gonna practice on/talk to?) > Some do learn Indonesian or Japanese, but most don't bother. What? Have we found in the Aussies a nation who are even worse at foreign languages than the British? I never thought I'd live to see the day! ;-) > 2) You don't need a passport to drive across the road. Or travel 2000km for > that matter. Well, we're like that in the UK, except that the island is smaller. > 3) 240VAC 3 pin sockets are a national standard. That doesn't seem to have helped us... > CNN is about the nearest I get. Upside is that I can now read most of the > Cyrillic alphabet after 4 weeks of watching snippets of Serbian TV news > subtitles! > (Well I can read Belgrad(e) Pristina and Novi Sad anyway) Watch out! The Serbian alphabet is as different from the Russian alphabet (the de facto standard for Cyrillic) as the Polish alphabet is from the English alphabet... (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...) Philip.

26 years, 8 months

Don Lancaster was Re: Ebay Mark-8 Plans

by yakowenk＠cs.unc.edu

On 12 Apr 1999, Christian Fandt <cfandt(a)netsync.net> wrote: ] Well, so much for April 1st being the specific "Holiday of Jest" ;-) I much prefer "August Fool's Day". Nobody expects it. :-) Bill.

26 years, 8 months

Abort, Retry, Ignore, Fail? (Was: stepping machanism

by yakowenk＠cs.unc.edu

I'm almost afraid to ask this, but what language is the Perl interpreter written in? Bill. (K&R C rules! ANSI C is for wimps!) On 9 Apr 1999, Cameron Kaiser <ckaiser(a)oa.ptloma.edu> wrote: ] :: It's stupid to handle errors? Or are you saying one shouldn't be using C ] ::in the first place? ] ] The latter :-) ] ] :: -spc (Not that C is the best language ... ) ] ] I'm still kinda stuck on Pascal, myself. But I loves Perl.

26 years, 8 months

Abort, Retry, Ignore, Fail? (Was: stepping machanism

by yakowenk＠cs.unc.edu

It is not such a great testimonial when you admit that you like it because they paid you for it. :-) Reminds me of the spoof interview with Staunstrup about C++ ... Bill. On 9 Apr 1999, Ethan Dicks <ethan_dicks(a)yahoo.com> wrote: ] I am presently paying for my classic computer hobby by crafting perl for 50+ ] hours per week at consultant's wages. I *love* perl!

26 years, 8 months

Signal detection

by CLASSICCMP＠trailing-edge.com

>Could anyone tell me how a radio detects signals vs. static? There is a >little gauge on my radio that moves depending on the amount of noise vs. >signal. I would guess that the digitally tuned radios that skip over the >frequencies that are pure static work in the same way. What is this way? Generally the gauge is a reading of the AGC (automatic gain control) level being applied by the radio's IF. There are many other ways to derive this signal, but this is the most common one. -- Tim Shoppa Email: shoppa(a)trailing-edge.com Trailing Edge Technology WWW: http://www.trailing-edge.com/ 7328 Bradley Blvd Voice: 301-767-5917 Bethesda, MD, USA 20817 Fax: 301-767-5927

26 years, 8 months

Has anybody heard from Wirehead?

by fauradon＠pclink.com

Well I finally got my shipment today. Still no word from him though. Francois >He cashed mine about a month ago and I also Have had very little contact >with him. Last I got was that he was traveling or otherwise swamped by his >job. His last e-mail stated that he'll ship on monday and confirm by e-mail >but I have not received such confirmation... I'm getting impatient too... > >Francois > >>I haven't heard from him either. He cashed my check on April 5, 1999. Let >me >>know if you hear from him. >> >> >

26 years, 8 months

AMPRO LITTLE BOARD, etc.

by edick＠idcomm.com

Golly! I wasn't aware that they actually put a SCSI controller on the board. That must have been several rev's later than mine. My two boards were the beta and first release. I put a couple of hundred of these into the field because I liked them and they allowed pretty compact packaging. Take a look at some comments in-line below, please. regards, Dick -----Original Message----- From: Allison J Parent <allisonp(a)world.std.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Friday, April 16, 1999 6:35 PM Subject: Re: AMPRO LITTLE BOARD, etc. ><I bought mine new as a kit in '83, as part of the first production run. ><They didn't have HDD support then, and since I made and sold an adapter ><daughterboard to interface to Z-80 processor sockets, one of several, I wa ><not concerned about that. The board always worked reliably and, aside fro ><the occasional need to read a standard diskette, the system was pretty ><complete. > >Mine is only slightly later, has the 5380 scsi chip. > ><Well, the drive attached to my two boards, i.e. the hard drive, is an ST-50 ><that was lying about some fifteen years ago when I happened to need a drive > >The sequence of disks over the years for the HDD side: > > xybec and st506 bought new in 82(late). Still have both. > Adaptec, and Quantum D540 (31mb) much faster. > the adaptec died and the xybec was in with a st251 for a while > then the fujitsu 3.5" scsi drive. > I was propping the door to a room in the basement with a couple of 10MB RODIME 3.5" drives which might work really well with this arrangement. I once ran one of these with a 1"-high 3.5"Sony drive which a PC believed was a 1.2MB drive. Maybe I can fool the FDC drivers into doing a similar thing. That would be handy. There's no "standard" 3.5" driver for CP/M. > ><>supported. The host interface was very similar in concept and nearly ><>in execution as IDE. >< >< ><The history included in the IDE spec clearly indicates that it was patterne ><after the 1003-WAH board (of PC/AT fame), which is the PC-bound eqivalent o ><the 1002. It uses the same IC's, hence the same command structure and bit > >Here we go again... I DIDN'T SAY IT WAS IDE. I said it was similar in >respect that it was a bus level interface for a controller and predates >IDE. I do know that the wd1003 was what the IDE base design was patterned >after. No, you surely didn't say that! It doesn't use the same cable definition or any thing like it. It just happens to use a 40-conductor cable. The reason I said I'd try modifying the firmware to talk to an IDE drive is that there is reason to believe that the command structure is identical although the hardware would have to be modified to load the registers as it's done on the 16-bit -WAH controller. The fact is that the 1000-05 and the 1002-05 bridge controller boards use the same chip (WD1010-05) as the HDD interface. That's where the command registers are located and they'll require programming in the same way. Since the IDE drive has, essentially, the same register set on it to accomplish the controller functions, and the register set mapped in the same way as the WD1003-WAH, it should be possible to make it work similarly. ><definitions. I'm inclined to try hooking an IDE drive up in place of the ><1000-05 board and ST-506 drive just to see what it does. I'd imagine they ><emulated it faithfully. > >>From the programming I did in the late 80s with them I'd say they did. > ><The WD hardware required a fair amount of time to do its job, particularly ><the BMAC chip, which is really just an 8042. The access time for which th ><WD controller series was built was a bit slower than the access window fro ><a 4 MHz would consistently allow. Consequently, I put a device specific ><wait-state generator on my adapter daugherboard. It decoded the address an ><generated a wait only for this one device, since the AMPRO guys, or whoeve ><else generates wait-states when they think they're needed could still do i ><on their own for other devices. > >Explains alot. the first hard disk system I had was S100 so the standard >for performance was already set in my mind by '83. > ><Yes. I have a bunch of the ADAPTEC 4070 bridge controllers left over from ><something. They record in RLL code, so the "little" drives I used to use a ><doorstops, etc, (ST506, TM602, SA6-whatever) can be nearly a full CP/M ><"volume," i.e. they hold about 7.2 MB which is nearly the max for a CP/M ><drive size. It works out well. > >I have one of those that replaced the MFM one from way back. > ><I wasn't aware that ZILOG or MOSTEK had 8MHz peripherals, though it doesn' ><surprise me. I ws siphoned off into a bunch of 8748/8751 stuff in mid-1983 ><and stopped following the Z-80 for a while. By the time I was able to com > >Finding them can be tough. the 6mhz are more common. 8530s or 8330s are >easier to find and offer better perfomance. > I'm really not that hot for it, but think it would be charming to put a set of '-H' parts in an early AMPRO Little Board and make it work at 8MHz. The timing should work with 100ns DRAMs. Aside from the PROM, I doubt anything other than the peripherals would be affected by the speed change. Of course the FDC would require a different tap from the clock divider, but everything else should work as is, save, perhaps the PROM. The PROM might work if the clock switch were hacked as well. (I believe there was a little sorcery with switching the clock speed after copying the PROM into RAM, by switching the preset on a counter. What I liked about this was the really sensible packaging you could use with these small boards. I have a video display/keyboard on a similar form factor which I'd really like to package with these other two boards and the drives. That would be truly minimalist for the time. > >Allison > >

26 years, 8 months

8" drive on a pc controller

by edick＠idcomm.com

I had a number of double-headed drives, including Shugart 851's, Mitsubishi whatevers, Qume DT-8's, and some NEC and Tandon half-height models, all of which were operated at 3 ms. I've got the spec's for all of them so I can verify whether they should indeed operate at that rate. Only the single-headed drives were typically slower, IIRC. The distinction, I believe, is that the "slow" drives use lead screws to position the heads while the quicker ones use a band actuator. What I find puzzling about this is that the 5.25" half-height drives, virtually all of which were capable of the higher speed, were not set up for the higher speed in the default on PC's. I wasn't aware that the NEC controller chip had a problem with the step rate. I stuck with WDC FDC chips in my own applications. Dick -----Original Message----- From: Allison J Parent <allisonp(a)world.std.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Friday, April 16, 1999 6:35 PM Subject: Re: 8" drive on a pc controller ><Please forgive my interloping, here, but my SHUGART and Siemens SD 8" drive ><are spec'd for 6 ms step rate, and the double-headed types for 3 ms. It's ><really best (mechanically) to step these babies as fast as they will go, an ><it's quieter too. > >Be specific on the model as the sa800s and 850s would never do 3ms! Though >the later ones did step faster. The problem with 8" drives are that there >were some that were doing their best at 10-12mS and a few like CDCs 3ms >was the norm. Most fell in around 6mS. > >ALSO, the PC controller uses the 765 chip (or it's core) generally and >that chip can truncate the first step pulse by 1/2mS (8/5"). So the >fastest recommended step rate programming (srthut in SPECIFY command) >is 4mS. I believe it was never fixed. > >Allison >

26 years, 8 months

temporarily unsubscribing

by max82＠surfree.com

Hi, I'm removing myself from the list until wednesday, since I will be unable to check my mailbox during that period. Please, e-mail requests privately or wait until wednesday. --Max Eskin (max82(a)surfree.com) http://scivault.hypermart.net: Ignorance is Impotence - Knowledge is Power

26 years, 8 months

Jump to page:

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