test-drb July 2004

test-drb@ccmp.vtda.org

259 participants
518 discussions

Lucas Electrics: RE: Commodore Pet ROM trouble... EPROM Substitutes...

by donm＠cts.com

On Fri, 30 Jul 2004, Joe R. wrote: > At 04:41 PM 7/29/04 -0700, you wrote: > >>> That's called a 'Light Emitting EPROM' and it's an expensive and > >>> short-lived alternative to an LED. > > > >>Is this related to things like the SER (Smoke Emiting Resistor -- one > >>where the power rating is massivle exceeded), SEC (Sound Emitinf Capacitor > >>-- an electrolytic wired backwards), the Friode (a diode that's > >>open-circuit both ways), etc? > > > >Sounds like what Lucas Electric used to use. > >http://pw1.netcom.com/~krk/lotus/humor/lucasjokes.html > > ROFL! Only someone who's had a vehicle with Lucas electronics could > truely appreciate that! > > Joe (x-1952 MG TD) ...or had experience with Magneti Morelli eqquipment! xxxxxxx Marelli - don

20 years

a classiccmp electronics project?

by dwight.elvey＠amd.com

>From: ard(a)p850ug1.demon.co.uk > >> >> Tony wrote... >> > Yes, modern SRAM is fast enough. But that's 'easy' in theory. Firstly you >> > have to have some way of switching the SRAM between the device and the >> > loader >> Dual port SRAM is one answer. Or, I'm not sure what the power on test in > >Sure, but have you looked at the price :-) Hi You use single port RAM with an output buffer ( could even be a 7404 but it would most likely need a 3state control, '240 or '244 ). You hold the machine in reset while you transfer data to the RAM ( It doen't make much sense to do it on the fly with the machine actually running ). This isn't much more complicated than a memory board. Dwight > >> microcode does on the MX's, but my guess is it doesn't touch the add-on >> microcode. The loader roms probably aren't touched either until called from >> the front panel. If the RPL stuff is turned on, it may though. I think the > >OK. I was thinking about the microcode ROMs in an HP9810 (somethign that >_I_ am working on, and those are most certainly 'hit' as soon as INIT is >deaseserted and the microocde program counter starts to change. I prefer >to think of general-purpose solutions (i.e. somethign that will replace >every 256*4 ROM), rather than soemthing that works only in specific >machines under specific circumstances. > >-tony > > >

20 years

Commodore Pet ROM trouble... EPROM Substitutes...

by RMaxwell＠atlantissi.com

On 2004-Jul-22 13:09:46 Wolfgang wrote: > > Mentioned TMS2532 Eproms are one of these Unobtainiums here. I've had better luck finding Hitachi's HN462532G version here... in Canada. That may be worth checking for. > Looking at the Pinouts I have in my databooks there are > little (minor?) Differences to the standard 2732's (besides > the different Program Supply Voltage). I couldn't find much 2732 and 2532 program at +25V, 2732A programs at +21V. +25V is fatal to 2732A. Don't ask me how I know that. > ressources online, but would it work if I made a small > adapter like "illustrated" below... > > 2732 2532 > EPROM -> SOCKET > Pin(s) Pin(s) > 1-17 -> 1-17 > 18 (E) -> 20 (PD/PGM) > 19(A10)-> 19 (A10) > 20(GVpp)> 21 (Vpp) No. The 2532 Vpp is always +5V when reading, and would keep 2732 outputs always OFF. The 2532 has just one enable pin, while the 2732 has two. Better to tie 2732-20 to 2532-18 (or to GND - outputs would be always enabled when the chip is selected). > 21(A11)-> 18 (A11) > 22-24 -> 22-24 > > Please correct me, if I'm completely wrong and trying to do > something impossible. Impossible? Nothing's impossible. Messy and difficult, maybe. > 2732's would be easy to obtain, and I have some > prommer-schematics and software handy. So it would be cool > if I could use them. > > Regards, > Wolfgang At VCF East 2.0 I brought along an EPROM programmer and some blank 2532s... not that you would have considered that to be East at all... ;o) Best of luck, Bob

20 years

Old EPROM questions again, EPROM Programmer

by rigdonj＠cfl.rr.com

At 07:20 PM 7/27/04 +0200, you wrote: >Hi all, <big snip> My (maybe dumb) >question: Does >anyone have some schematics and software (would be great) >for a little >homebrewed Eprom Programmer which works with a standard PC >parallel-port or >ISA slot? This would be a great project for rainy winter >days :) Why bother? You can buy them cheaply and easily, both new from the manufacturer's and used from E-bay. Yeah, Yeah I know someone will say it's an eductional thing but hanostly can't you find a better way to use your time than to reinvent the EPROM programmer for the 10,000th time? Joe > >Best Regards, > Wolfgang > > > > > >==================================================== >Ing. Wolfgang Eichberger cell.: +43-664-240-65-92 > http://www.eichberger.org > email: wolfgang(a)eichberger.org >---------------------------------------------------- >Gruentalerstr. 24 - 4020 Linz ? AUSTRIA >==================================================== >

20 years

Can anyone identify this portable?

by Innfogra＠aol.com

There was a clone case like this that you could put any XT board in. Check the BIOS. Very limited production. Paxton Astoria, OR

20 years

Old EPROM questions again, EPROM Programmer

by technobug＠comcast.net

On Jul 30, 2004, at 10:00 AM, cctalk-request(a)classiccmp.org wrote: At 08:59 PM 7/29/04 -0600, Ben wrote: > I would like to create several PCB's > rather than wire wrap but I have yet to find good information on PCB > layout guide lines > Check out <http://www.edwardrhamilton.com/titles/3/2/0/3202275.html> CRC

20 years

OT-ish - converting hex output to binary on a Unix platform

by pete＠dunnington.u-net.com

On Jul 30, 12:51, Jules Richardson wrote: > > I have a few files in hex format (actually ROM dumps) and want to > convert them to binary. Sort of the reverse of the hexdump utility. I'm > not aware of a standard (and probably on-topic!) Unix util to do this, > but maybe someone knows if there is one, or a handy way of doing this > using some of the standard text-processing utils that Unix has... mload will do this for Intel HEX files and patches, but it sounds like your files aren't quite the same as Intel HEX. However, the source code can be modified. http://www.dunnington.u-net.com/public/IntelHEX/ contains the tar file, but the important bits are also at http://www.dunnington.u-net.com/public/mload.c http://www.dunnington.u-net.com/public/mload.1 It's an implementation I did years ago of a common CP/M program called, not surprisingly, mload. -- Pete Peter Turnbull Network Manager University of York

20 years

First computer with real-time clock?

by toresbe＠ifi.uio.no

I actually could swear I'd read somewhere that the MIT whirlwind had a clock, it was a mechanical contraption or something. I'll stop by the informatics library which has a book on the Whirlwind. (I'm picking up the Teletype to take it home and work on it here!:) -tsb

20 years

OT-ish - converting hex output to binary on a Unix platform

by paulrsm＠buckeye-express.com

I use MS-DOS, not Unix, and I always solve the problem of converting a hex dump to a binary file using two standard tools: a text editor and an assembler. > (files are in the format of 16 pairs > of uppercase hex digits per line, > with a trailing space after every > pair - even the last one on a line) So a sample line might be "00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F " Adjust the following steps for your assembler. Delete trailing spaces, convert every space to ",$", and add " DB $" to the beginning of every line: " DB $00,$01,$02,$03,$04,$05,$06,$07,$08,$09,$0A,$0B,$0C,$0D,$0E,$0F" Add any required directives (ORG, END, etc.) and assemble. -- Paul Monroe, Michigan USA

20 years

OT-ish - converting hex output to binary on a Unix platform

by dwight.elvey＠amd.com

Hi If I was doing this on a Intel ISIS II system, I'd use an editor called X1.11. Although, there are languages like Perl that specifically handle text input streams, most any language can handle this conversion. I believe I have written this very same function in at least 3 different languages at one time or another. I know I've done it in BASIC, 8080 assembly and Forth. The concept is always the same. 1. Get a line 2. parse the line into words( hex digit pairs ) 3. Translate the hex into binary 4. write that to an output file. One just repeats this until done. Of course, one may optimize things by buffering input and output in sizes that are similar to the storage media. Translation can be any of a number of methods. Even a translation table although I think I've always done it by doing calculations on the ascii value( some languages get in the way by requiring casting between data types ). Dwight >From: "Jules Richardson" <julesrichardsonuk(a)yahoo.co.uk> > > >Silly question, but maybe someone here's found a nice way of doing this >using standard Unix tools... > >I have a few files in hex format (actually ROM dumps) and want to >convert them to binary. Sort of the reverse of the hexdump utility. I'm >not aware of a standard (and probably on-topic!) Unix util to do this, >but maybe someone knows if there is one, or a handy way of doing this >using some of the standard text-processing utils that Unix has... > >(files are in the format of 16 pairs of uppercase hex digits per line, >with a trailing space after every pair - even the last one on a line) > >I'm rapidly coming to the conclusion that I need to remember some C >again - and I've only just finished emptying my brain of it after the >last time I needed to code in it a couple of months ago :-) > >cheers > >Jules > >

20 years

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test-drb July 2004