- test-drb@ccmp.vtda.org - classiccmp.org

by owad＠applefritter.com

>BTW, I also have a tempest Macintosh 512K, and a tempest HP inkjet >printer. I guess I now have enough stuff to create a collecting >subcategory :) What's your tempest Mac 512K like, Sam? Is it similar to the one I've got at <http://www.applefritter.com/macclones/techmatics/index.html>? Tom Owad ---------------------------Applefritter--------------------------- Apple prototypes, Apple II & early Mac clones, and the Compubrick. ------------------<http://www.applefritter.com/>------------------

26 years, 11 months

2
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Semi-OT: routing

by jlwest＠tseinc.com

I assume your netmasks are 255.255.255.0, and you don't have a default gateway set? Could also be bad cable, hub, etc... What about other traffic of a tcp nature rather than udp - such as telnet, ftp, etc... of course making sure these services are enabled in inetd.conf (followed by a sighup to inetd)? Are you sure the ip information is really set on the sun (ie. what does ifconfig -a show, is the interface marked up, etc.?)?? Jay West -----Original Message----- From: John Foust <jfoust(a)threedee.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Tuesday, August 03, 1999 4:53 PM Subject: Re: Semi-OT: routing >At 05:27 PM 8/3/99 -0400, you wrote: >> >>I'm trying to network my SparcII to my p166 running Linux (and ultimately >>my VAXstation and Sun 3/60). No matter how hard I try or which >>configurations I use, I can't ping from my Sparc [196.168.1.2] to my p166 >>[192.168.1.1]. I dropped a Win98 box on the network and set it up as >>192.168.1.3. I could ping ...2 but not ...3. I could ping ...3 from ...2. >>But neither box is talking to ...1. > >Sounds like a bad cable or hub. Which cable type are you using? > >- John > >

26 years, 11 months

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Semi-OT: routing

by a2k＠one.net

This is only semi-ot because it involves my SparcII, which I can't seem to find the date on right now, but I'm pretty sure it meets the requirement. At any rate, please contact me off-list to avoid cluttering it up. I'm trying to network my SparcII to my p166 running Linux (and ultimately my VAXstation and Sun 3/60). No matter how hard I try or which configurations I use, I can't ping from my Sparc [196.168.1.2] to my p166 [192.168.1.1]. I dropped a Win98 box on the network and set it up as 192.168.1.3. I could ping ...2 but not ...3. I could ping ...3 from ...2. But neither box is talking to ...1. I know it works because the ethernet card is configured in the kernel, I see it get recognized at boot up, I can set the IP with ifconfig. I've read all my books about it, the man pages, the NETWORKING-HOWTO and the Ethernet-HOWTO as well as asking in #linux on effnet. This is a last resort. Thanks, Kevin ------------------------------------------------------------------------------- "It's you isn't it? THE BASTARD OPERATOR FROM HELL!" "In the flesh, on the phone and in your account..." -- BOFH #3

26 years, 11 months

2
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(no subject)

by edick＠idcomm.com

My apologies, folks . . . this one's clearly misrouted. Dick -----Original Message----- From: Richard Erlacher <edick(a)idcomm.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Tuesday, August 03, 1999 2:14 PM Subject: Re: (no subject) >Since I have their latest CD, I have all the data sheets. What I'm after is >the information about the logic cell resources, clock drivers, routing >resources, etc, generic to each family and not specific to a given device. >The individual sheets seldom have that data. > >regards, > >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: Tuesday, August 03, 1999 11:11 AM >Subject: Re: (no subject) > > >>> > A 99/4A can range from USD 2,- (just the unit in used condition) >>> > up to USD 30-70 (New, unused, original packed, never opened with >>> > no damages on the box). PS: The white units may score way higher >> >>> Hans, I don't know about you wacky Germans, but any American paying >>> USD$30-70 for a TI-99/4a in ANY condition would be a fool and a half. >>> Maybe if it was gold plated, or the President used it to fondle an >intern, >>> then maybe. But I just passed up on two TI-99/4a's in the box without >>> even a second thought. >> >>> New, unused, original packaging and never opened with no damage to the >box >>> is not hard to find (ok, except for "never opened", but still). Maybe >>> USD$10-$25. >> >>Just catch the next for me (never opened!) >> >>TI wasn't the real big thing over here. >> >>> > in Europe, since they never where sold in masses over here. PPS: >>> > a Ti 99/4 (no A) will also range higher, especialy when in mint/ >>> > unused condition. >> >>> I just paid $90 for future reference. A bit more than I wanted to pay >but >>> then how many 99/4's does one come across? In my experience of >collecting >>> for many years, the answer is not many at all. >> >>USD 90,- is quite high - it may need a second thought. >> >>> > A Timex/Sinclair may earn you USD 2-5 (used, with PS) or score >>> > a whooping USD 50,- as a new never opened box. >> >>> Repeat same discussion as above. You can buy new ZX-81's from that zebra >>> website for US$29 or whatever it is. >> >>Well, you might notice, in both cases that the high prices >>are ment for top notch stuff, and, as my mother said: >>Every day a dumb one lifts his head - you just have to catch him... >>(As I have seen the original question was about for what he might >>sell his stuff (jep, of course, take an auction (rarerarerare:))) >> >>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, 11 months

1
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DUMB VMS!

by jritorto＠nut.net

I do not like this VMS. I like RSX and RT, but not VMS. First of all, it's running on a 32-bit machine and it isn't UNIX. That's just offensive. Then, second, it won't let me log in because I don't remember any of the passwords. I even tried the boot/r5:1 and uafalternate thing, but it still won't let me type in bogus login info. What a pain. If anyone knows how to get around this, please mail me back. I have a really important file on this silly vax and need to save it on a machine that I do backups on regularly. Then I'll be free to run NetBSD. Instead of that dumb VMS. ;^) jake

26 years, 11 months

4
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(no subject)

by edick＠idcomm.com

Since I have their latest CD, I have all the data sheets. What I'm after is the information about the logic cell resources, clock drivers, routing resources, etc, generic to each family and not specific to a given device. The individual sheets seldom have that data. regards, 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: Tuesday, August 03, 1999 11:11 AM Subject: Re: (no subject) >> > A 99/4A can range from USD 2,- (just the unit in used condition) >> > up to USD 30-70 (New, unused, original packed, never opened with >> > no damages on the box). PS: The white units may score way higher > >> Hans, I don't know about you wacky Germans, but any American paying >> USD$30-70 for a TI-99/4a in ANY condition would be a fool and a half. >> Maybe if it was gold plated, or the President used it to fondle an intern, >> then maybe. But I just passed up on two TI-99/4a's in the box without >> even a second thought. > >> New, unused, original packaging and never opened with no damage to the box >> is not hard to find (ok, except for "never opened", but still). Maybe >> USD$10-$25. > >Just catch the next for me (never opened!) > >TI wasn't the real big thing over here. > >> > in Europe, since they never where sold in masses over here. PPS: >> > a Ti 99/4 (no A) will also range higher, especialy when in mint/ >> > unused condition. > >> I just paid $90 for future reference. A bit more than I wanted to pay but >> then how many 99/4's does one come across? In my experience of collecting >> for many years, the answer is not many at all. > >USD 90,- is quite high - it may need a second thought. > >> > A Timex/Sinclair may earn you USD 2-5 (used, with PS) or score >> > a whooping USD 50,- as a new never opened box. > >> Repeat same discussion as above. You can buy new ZX-81's from that zebra >> website for US$29 or whatever it is. > >Well, you might notice, in both cases that the high prices >are ment for top notch stuff, and, as my mother said: >Every day a dumb one lifts his head - you just have to catch him... >(As I have seen the original question was about for what he might >sell his stuff (jep, of course, take an auction (rarerarerare:))) > >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, 11 months

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DUMB VMS!

by edick＠idcomm.com

Yes. That's the reason it was so popular with certain government agencies when I worked in the Military/Industrial complex. VMS was multi-level secure while UNIX, at least then, was full of holes. Dick -----Original Message----- From: Jim Strickland <jim(a)calico.litterbox.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Tuesday, August 03, 1999 1:33 PM Subject: Re: DUMB VMS! >Um, while I fail to understand why VMS is dumb for not letting you in without >the right passwords, I realise that's not very helpful to you. :) Hit the >web page at http://www.geocities.com/SiliconValley/Lakes/2956/data.htm >and search for the word "password". It lists the procedure. > >And at the risk of starting a religious war between the VMS folk and the >unix folk, let me say just that VMS and Unix are good at different things. >VMS is much much more secure than unix, and has far greater ability to give >users *some* privilages without giving them *everything*. This is valuable >in some circumstances. Unix probably does get better overall performance >for the same hardware because it doesn't have this security overhead, among >other things. > > >Hope this helps. >-jim > >> >> I do not like this VMS. I like RSX and RT, but not VMS. First of all, >> it's running on a 32-bit machine and it isn't UNIX. That's just >> offensive. Then, second, it won't let me log in because I don't remember >> any of the passwords. I even tried the boot/r5:1 and uafalternate thing, >> but it still won't let me type in bogus login info. What a pain. >> >> If anyone knows how to get around this, please mail me back. I have a >> really important file on this silly vax and need to save it on a machine >> that I do backups on regularly. Then I'll be free to run NetBSD. Instead >> of that dumb VMS. >> >> ;^) >> >> jake >> > > >-- >Jim Strickland >jim(a)DIESPAMMERSCUMcalico.litterbox.com >----------------------------------------------------------------------- > BeOS Powered! >-----------------------------------------------------------------------

26 years, 11 months

1
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DUMB VMS!

by CLASSICCMP＠trailing-edge.com

>offensive. Then, second, it won't let me log in because I don't remember >any of the passwords. I even tried the boot/r5:1 and uafalternate thing, >but it still won't let me type in bogus login info. What a pain. >If anyone knows how to get around this, please mail me back. You want to read the OpenVMS FAQ (see http://www.openvms.digital.com/wizard/openvms_faq.html ), specifically "MGMT5. I've forgotten the SYSTEM password - what can I do?". It walks you through step-by-step, and best of all tells you how to do it without UAFALTERNATE set to 1. -- 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, 11 months

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More TI web sites

by dastar＠ncal.verio.com

Wow, this is right from TI's web site: http://www.ti.com/calc/docs/994a.htm They even refer you to a fan website. 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: 05/25/99]

26 years, 11 months

1
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Interesting TI 99/4a products

by dastar＠ncal.verio.com

Ok, I don't know if anyone else has ever seen this, but check out this web site: http://www.whtech.com/ti/ These guys are selling new TI 99/4a products. Ever heard of a SCSI adaptor for the 99/4a? This site has one! They used to have a product to hook an AT keyboard up to the TI. Pretty interesting. 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: 05/25/99]

26 years, 11 months

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Cool IBM PC find

by Philip.Belben＠pgen.com

> Ok, here's something very cool as far as IBM PC artifacts go. Its an "IBM > TPC 4 System Unit" (the model is 4459). Its a tempested PC! Its I don't remember the 4459 but I do remember seeing an IBM Tempest PC when I was working at IBM as a pre-university student. Very solid panels that all screwed into place, rather than the pressed sheet metal around three sides. I also recall filter components between connnectors on the back panel and the cards / motherboard ports to which they belonged. These all went in a cavity about 1.5 inches deep between the rear of the PC chassis and the actual back panel. Philip.

26 years, 11 months

2
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chinese and russian computer history

by Philip.Belben＠powertech.co.uk

Can anyone help this guy out? As usual, respond to him, not me (nor the list), please. Phikip. ---------------------- Forwarded by Philip Belben/PTech/PowerGen on 03/08/99 16:33 --------------------------- roinfo(a)knoware.nl on 28/07/99 22:04:04 Please respond to roinfo(a)knoware.nl To: history-of-computing-uk(a)mailbase.ac.uk cc: Subject: chinese and russian computer history Where do i find info on russian pre perestroika landmark computers and also info on chinese landmark computers Cornelis Robat ********************************************************************** This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This footnote also confirms that this email message has been swept for the presence of computer viruses. Power Technology Centre, Ratcliffe-on-Soar, Nottingham, NG11 0EE, UK Tel: +44 (0)115 936 2000 http://www.powertech.co.uk **********************************************************************

26 years, 11 months

1
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GridPad 1910 sales?

by sinasohn＠ricochet.net

At 11:47 PM 6/21/99 -0700, you wrote: >> ::Hi. A while back I was talking with Rodger on the list about the >> ::(appearant) abundance of GridPad 1910's that he was selling.... did th >He's around. Probably just extraordinarily busy as usual. Give him a >day or two to respond to your e-mails. I'm behind. Can you tell? 8^) Since I started that project, a few things happened -- I got married, trashed a couple of hard drives, and my dad had another stroke. At this point, the GRiDPads are kinda sitting there, waiting to be retested, boxed, and shipped, but I'm spending all my time at the hospital (when not working) so it won't be anytime soon. When he comes home, I'll likely be spending a lot of time caring for him, so I can't say when I'll really be able to get to it. So, if you have another chance to get a cheap GRiDPad, go for it. If you're desparate to get one asap, let me konw and I'll see what I can do. Otherwise, feel free to tell me to bugger off, or invest the money elsewhere for the time being. I'm really sorry about the delay and confusion. --------------------------------------------------------------------- O- Uncle Roger "There is pleasure pure in being mad roger(a)sinasohn.com that none but madmen know." Roger Louis Sinasohn & Associates San Francisco, California http://www.sinasohn.com/

26 years, 11 months

2
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Cool IBM PC find

by SUPRDAVE＠aol.com

IIRC, IBM made several tempest models like the PC, XT and AT. very heavy duty, but never saw one in real life. I picked up a neat IBM part. It's a prototype AT adaptor never used and still in its worn out box. it's basically just a full length AT card with holes for soldering in chips and components. Will go good with my never used PC keyboard and 5150 still in their boxes... In a message dated 8/2/99 9:02:56 PM Eastern Daylight Time, dastar(a)ncal.verio.com writes: > Ok, here's something very cool as far as IBM PC artifacts go. Its an "IBM > TPC 4 System Unit" (the model is 4459). Its a tempested PC!

26 years, 11 months

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Epson HX20 question

by jpl15＠netcom.com

At the SoCal TRW swapmeet yesterday, I couldn't resist buying an Espson HX20, in it's brown plastic Epson carrying case, which included a couple of microcassettes. It powers on ok and basically seems to work, giving: CRTL/@ Initialize 1 MONITOR 2 BASIC 3 SkiWriter (TM) on the display; pressing 'MENU' or 'BREAK' restores the display, however choosing Basic or SkiWriter from the menu traps to: _ _ Trap! A=00 B=02 X=00FF C=D0 S=04AA P=00FF [Actually B=02 for Basic and 03 for SkiWriter.] Five ROMS are mounted, four for Basic and one for Ski. The dipswitch SW6 is 1,2,3=ON 4=OFF. That's all I know about it so far. I picked this up because it's a 'nostalgia' machine for me... I first saw one in the wretched computer store I worked at in the early 80's and couldn't afford it then. Later I did buy and use an older Epson Equity II (which I still have BTW). Any suggestions on how to make this little rig smarter? Cheers John. PS: The TRW Swap was great fun... Marvin, his friend Gyuari (from Hungary), Aaron Finney, and Dave Dameron stopped by... Paul Passmore showed up and we all looked for Mike Ford but he was in 'stealth' mode and eluded us. Marvin scored some cool vintage 8-bitters and I got some Real Old software and Games from a cow-orker that I need to sort out and offer to The List. Oh yeah... I bought a forlorn AT&T 3B2 700 in unknown shape, although the guy said it came out of service working fine.. When I get a Round Tuit, I'll probably have questions about the pinouts of the USOC jacks.. but for now on the shelf it goes... and it's *heavy*.

26 years, 11 months

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floppy disk drive manuals

by edick＠idcomm.com

Thanks for the information. Don Maslin sent some information which it turns out doesn't apply exactly to my particular drives, as some of the jumpers on his list dont exist, while others, on the drive, don't appear on the list. I'm not sure what that means, though. The drives had paper tags printed with dot-matrix which are mostly missing, and I'm quite certain the printed-on-foil labels are not specific enough to account for the different. Having re-jumpered the drives, they are able to read one another's writing, though I'm uncomfortable with some of the behaviors certain jumpers produce, particularly one, which seems to effect the drives differently. I've had these drives since they were a new product, but haven't looked at them since a couple of moves before I landed here ten years ago. I'm not in a hurry now that these drives are available for me to use to troubleshoot other drives, but when your scanner's back on line, I'd really appreciate a copy of the bitmaps. thanx, Dick -----Original Message----- From: Fred Cisin (XenoSoft) <cisin(a)xenosoft.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Monday, August 02, 1999 2:03 PM Subject: Re: floppy disk drive manuals >I have the "Operating and Service Manual" for the Tandon TM848-1 and 848-2 >8" drives. Since I still use some of those drives, I'm not willing to >part with them, but I could get copies made. Unfortunately it looks like >I won't have a working scanner at all this week. If you can help me >through what to look up, and teach me what to look for, I'd be glad to >check things for you. Let me know which sub-model you have. > >For example: >for motor speed, on the 848-1, trigger off of R33; for the 848-2, trigger >off of test point 12. > >For cat's eye alignment: >Channel A: Test point 2 >Channel B: Test point 3 >Ground: Test point 1 >External trigger: Test point 11, negative trigger, for single sided >drives, R33 is alternatre test point, negative trigger. Test point 12, >negative trigger for double sided drives. > > >Tony: >I also have manuals for the Sony D31V and D32V drives! > >-- >Fred Cisin cisin(a)xenosoft.com >XenoSoft http://www.xenosoft.com >2210 Sixth St. (510) 644-9366 >Berkeley, CA 94710-2219 > >On Fri, 30 Jul 1999, Richard Erlacher wrote: >> I have a couple of Tandon 8" slimline drives (They're in the basement and >> I'm not so no model number.) They clearly can't read one another's writing >> consistently, so I'm interested in alignment data as well as the jumper >> definitions. Would you have a manual which contains that information? I >> need to know what the jumpers are and do, and what the factory default >> settings are. I also need to know where the dif-amp outputs to be used for >> alignment are located, (pin numbers) as well as the index sensor pin and >> other signals used in adjusting these drives for radial head alignment, >> index alignment, track zero calibration, etc. If you have it and could >> email me that data, it would help greatly. >> >> regards, >> >> Dick >> >> -----Original Message----- >> From: Tony Duell <ard(a)p850ug1.demon.co.uk> >> To: Discussion re-collecting of classic computers >> <classiccmp(a)u.washington.edu> >> Date: Friday, July 30, 1999 7:23 PM >> Subject: Re: Cromemco 4FDC, How do you format a disk? >> >> >> >> true and for the data I gave the 125kbits/sec rate is too low. As it's >> >> minima was 250kbits/s is twice that! Part of the recording scheme is >> that >> >> there are rules for continous strings of 1s and 0s, they arent permitted >> >> to exist for clocking and bandwidth reasons. >> > >> >I've seen plenty of controllers and data separators that put limits on the >> >maximum number of consecutive pulses and gaps. That's why you need clock >> >pulses in MFM recording, and why Apple had the 5-3 and 6-2 encoder tables. >> >I have _never_ seen a drive (and I've read OEM and service manuals for all >> >sorts of drives) that specify any restrictions on the user data using the >> >standard encoding schemes >> > >> >At normal 5.25" data rates (125kbps (user bits) FM, 250kbps MFM) : >> > >> >Repeated MFM 0's looks like repeated MFM 1's looks like repeated FM 1's, >> >and consists of pulses every 4 us. >> > >> >Repeated MFM 1010... looks like repeated FM 0's, and consists of pulses >> >every 8us. >> > >> >Now, all drives support user sectors of 1024 bytes (8192 bits), MFM at >> >least (and I don't think this is a real limit of the _drive_ either). >> >That means you could have either of the above patterns for 8192 bits -- >> >the user bytes 'touch' each other with nothing between, and there's >> >nothing to stop you having a sector of 0's, a sector of FF's or a sector >> >of 55s if you want it. A disk drive that couldn't store said data would >> >not be useful. >> > >> >I've got a Sony 3.5" drive on the bench at the moment. Now this drive >> >rotates at 600rpm, so you would double the above data rates. Some of the >> >tests involve recording pulses every 2us (corresponding to the first case >> >above) and 4us (corresponding to the second case above) continuously for >> >one revolution and then playing them back. The service manual for the Teac >> >FD235 gives tests involving the recording and reproduction of 250kHz >> >(pulse every 4us) and 125kHz (pulse every 8us) waveforms. >> > >> >So it would certainly appear that these 2 drives could correctly handle >> >FM recording at half the user data rate of the standard MFM encoding. In >> >other words that Teac (720K) drive would handle FM encoding at 125kbps. >> > >> >-tony >> > >> >> > >-- >Fred Cisin cisin(a)xenosoft.com >XenoSoft http://www.xenosoft.com >2210 Sixth St. (510) 644-9366 >Berkeley, CA 94710-2219 >

26 years, 11 months

1
0
0 0

floppy disk drive manuals

by edick＠idcomm.com

Greetings! I have a couple of Tandon 8" slimline drives (They're in the basement and I'm not so no model number.) They clearly can't read one another's writing consistently, so I'm interested in alignment data as well as the jumper definitions. Would you have a manual which contains that information? I need to know what the jumpers are and do, and what the factory default settings are. I also need to know where the dif-amp outputs to be used for alignment are located, (pin numbers) as well as the index sensor pin and other signals used in adjusting these drives for radial head alignment, index alignment, track zero calibration, etc. If you have it and could email me that data, it would help greatly. regards, Dick -----Original Message----- From: Tony Duell <ard(a)p850ug1.demon.co.uk> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Friday, July 30, 1999 7:23 PM Subject: Re: Cromemco 4FDC, How do you format a disk? >> true and for the data I gave the 125kbits/sec rate is too low. As it's >> minima was 250kbits/s is twice that! Part of the recording scheme is that >> there are rules for continous strings of 1s and 0s, they arent permitted >> to exist for clocking and bandwidth reasons. > >I've seen plenty of controllers and data separators that put limits on the >maximum number of consecutive pulses and gaps. That's why you need clock >pulses in MFM recording, and why Apple had the 5-3 and 6-2 encoder tables. >I have _never_ seen a drive (and I've read OEM and service manuals for all >sorts of drives) that specify any restrictions on the user data using the >standard encoding schemes > >At normal 5.25" data rates (125kbps (user bits) FM, 250kbps MFM) : > >Repeated MFM 0's looks like repeated MFM 1's looks like repeated FM 1's, >and consists of pulses every 4 us. > >Repeated MFM 1010... looks like repeated FM 0's, and consists of pulses >every 8us. > >Now, all drives support user sectors of 1024 bytes (8192 bits), MFM at >least (and I don't think this is a real limit of the _drive_ either). >That means you could have either of the above patterns for 8192 bits -- >the user bytes 'touch' each other with nothing between, and there's >nothing to stop you having a sector of 0's, a sector of FF's or a sector >of 55s if you want it. A disk drive that couldn't store said data would >not be useful. > >I've got a Sony 3.5" drive on the bench at the moment. Now this drive >rotates at 600rpm, so you would double the above data rates. Some of the >tests involve recording pulses every 2us (corresponding to the first case >above) and 4us (corresponding to the second case above) continuously for >one revolution and then playing them back. The service manual for the Teac >FD235 gives tests involving the recording and reproduction of 250kHz >(pulse every 4us) and 125kHz (pulse every 8us) waveforms. > >So it would certainly appear that these 2 drives could correctly handle >FM recording at half the user data rate of the standard MFM encoding. In >other words that Teac (720K) drive would handle FM encoding at 125kbps. > >-tony >

26 years, 11 months

3
3
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Micro-stories for 2nd ed of A Guide to Collecting.

by kstumpf＠unusual.on.ca

The book, A Guide to Collecting... has been both mis-represented and criticized as being for mainframe collectors. That confuses me so I solicit your help in making the 2nd edition for everyone in the hobby. Please send your ideas, especially your acquisition and restoration stories involving microcomputers (PC, etc. = microcomputer). You know, the type of story where you discovered the exact rev. of a certain I/O board while browsing through a china cupboard in an antique shop while you waited for your car to be repaired. That kind of story. Please send them to me directly. Thank you very much. ---------------------------------------------------------------------------- ------------------------------- Kevin Stumpf * Unusual systems * www.unusual.on.ca +1.519.744.2900 * EST/EDT GMT - 5 Collector - Commercial Mainframes & Minicomputers from the 50s, 60s, & 70s and control panels and consoles. Author & Publisher - A Guide to Collecting Computers & Computer Collectibles * ISBN 0-9684244-0-6 .

26 years, 11 months

2
1
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Carts/connector cleaning

by a2k＠one.net

Hello, time for the yearly nostalgia. I have quite a collection of NES stuff (carts and consoles) that I've rescued from trash, garage sales, etc. that has been sitting in my basement for a few years. Trying to run one of the games produces odd output (i.e. lines down it display, not booting entirely) which I know is due to dirty contacts. What's the best way to clean these? Alchohol on a swab? Freon? (I have a friend that bought out a very large supply of it just before it became illegal to sell (i.e.: 100+ bottles for his reel-to-reel tape recorders) Kevin ------------------------------------------------------------------------------- "It's you isn't it? THE BASTARD OPERATOR FROM HELL!" "In the flesh, on the phone and in your account..." -- BOFH #3

26 years, 11 months

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GPIB,'C' and the HP-150 (was:Re: Tek 4041)

by jeff.kaneko＠juno.com

On Thu, 29 Jul 1999 22:58:15 -0500 "Roger Goswick" <ccfsm(a)ipa.net> writes: >Say, while I'm wasting everyone's time, where might I obtain a boot >disk for my HP 150? Would any version of Dos 2.1 work or do I need >an HP version. And many thanks all. This really is a swell bunch of >people you have here!! It's special. The IBMBIO.COM has all of the hardware specific drivers for the thing, and it's specially written for the 150's IO system, namely HPIB. Somebody's *bound* to have a copy somewhere . . . My local surplus dealer had Touchscreen II's. I imagine I can get one pretty cheaply . . . Jeff ___________________________________________________________________ Get the Internet just the way you want it. Free software, free e-mail, and free Internet access for a month! Try Juno Web: http://dl.www.juno.com/dynoget/tagj.

26 years, 11 months

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GPIB,'C' and the HP-150 (was:Re: Tek 4041)

by jeff.kaneko＠juno.com

On Thu, 29 Jul 1999 21:51:04 Joe <rigdonj(a)intellistar.net> writes: >Tony, > >At 11:16 PM 7/29/99 +0100, you wrote: >>> , but >>> >doesn't the HP150 have an IEEE-488 port (aka GPIB, HPIB) as >>> >standard. >>> >>> Yes, it does but the 150 uses the port to connect to peripherals >>> operating under MS-DOS. It has no commands that will let you send or >>> recieve specific strings over the HP-IB. >> >>That's news to me (and I guess to HP). The HP150 Technical Reference >>Manual has a section entitled 'HPIB Interfacing' which describes how to >>use the HPIB port for non-disk devices. >> > > THAT's news to me! I've never heard of using a 150 as a HP-IB >controller and I have a large STACK of 150 documentation and none of >it even hints that you can what you're talking about. Can you make a >copy of that for me? S@#* and I've got a pile of 150s setting out in the >rain cause I had no use for them! Now see, I figured that you knew this, Joe. I remember when I was working for motorola, they tried to market an automated radio test system that used an HP-150 as an instrument controller, attached (via GPIB) to a service monitor, and a *BIG* interface box called a 'barn' that routed the audio, PTT, etc. It didn't sell. The application software sucked. <SNIP> > In C? Is there a C that will run on the 150? Most of the software >has to be tailored specificly for the 150 or else be VERY MS-DOS >compatible with no short cuts. I've heard of BASIC, Assembler and Pascal that >will run on the 150 but I haven't heard of a C compiler that would. I suspect any version of 'C' that is a straight command-line c-compiler *ought* to work (using dos calls only, of course). Hmmm. Turbo C 1.0 comes to mind. The hard part will be getting the HP-150 implementation of dos 2.x (or better, 3.x). Dang it Joe, see what you've done? Now I have to buy an HP-150 to try this out. S@#*. :^) Jeff ___________________________________________________________________ Get the Internet just the way you want it. Free software, free e-mail, and free Internet access for a month! Try Juno Web: http://dl.www.juno.com/dynoget/tagj.

26 years, 11 months

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What is a RL02K-DC?

by CLASSICCMP＠trailing-edge.com

> All of my "Digital" badged RL02 packs bear this nomenclature. > > The other companies' packs (BASF, Memorex, etc) do not. > > I have about 25-35 diskpacks actually made by (or sourced by) >Digital, and they all are RL02K-DC. "DC" stands for "Data Cartridge". There are also "RL02K-EF"'s, which are guaranteed error-free. (And RK05-EF's, and RM03-EF's, etc.) You frequently find the "-EF"'s coming from sites that ran Unix, as Unix doesn't deal very well with errors at all... Tim.

26 years, 11 months

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RT-11/RSX-11/RSTS freeware CD-ROM

by GOOI＠oce.nl

[snip -- deteled the original message to save bandwidth] Hello Tim. Count me in for the RT11 and the RSX CD-ROM. For RSX, I think as you stated, flavor 2C is the best option as I do not have a modern RSX version running on my 11/35. When the number of CD's to be burnt is clear I guess we all on the List will hear how to reward your effort ($$$). Happy PDP-ing, Henk Gooijen Nederweert-Eind Netherlands gooi(a)oce.nl

26 years, 11 months

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d'oh! that's Berkeley, of course...

by dogas＠leading.net

- Mike: dogas(a)leading.net

26 years, 11 months

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possibly need a systems pickup in Berkly, CA

by dogas＠leading.net

Anyone near there and willing to pick up a few systems (three Heathkit H-89's ) and pack and ship??? Thanks - Mike: dogas(a)leading.net

26 years, 11 months

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OT: Power Supply voltage for Dayna Etherprint-T plus?

by mtapley＠swri.edu

All, My apologies. Dayna's web site says "Farewell", and the intel site to which it points gave it a good try but didn't answer the question. I recently got a Dayna Etherprint-T Plus but not the power supply for it and i have no idea what voltage or current it needs. I'm pretty sure the unit is later than 1989 but if anybody has one and could check out the power supply to see what it says and email me off-list, I'd appreciate it very much. Thanks! - Mark

26 years, 11 months

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Also Available: RL02 Packs

by ethan_dicks＠yahoo.com

--- Kevin McQuiggin <mcquiggi(a)sfu.ca> wrote: > Hi Gang: > > I also have about ten extra RL02 packs, if anyone needs any. They even have > possibly useful stuff on them, e.g. VMS 5.2, VAX diagnostics, RT-11. Do you have any way of archiving the data off to 10Mb physical backup files? -ethan === Infinet has been sold. The domain is going away. Please send all replies to erd(a)iname.com _____________________________________________________________ Do You Yahoo!? Free instant messaging and more at http://messenger.yahoo.com

26 years, 11 months

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Your note

by allisonp＠world.std.com

<Allison, received your note and check yesterday. Thank you. That is what <cracks are for, isn't it? :) Glad the board works well. Yes, but, I only play a blonde on TV. ;) It's interesting to see the board with out all the hacks I'd gotten with the first one back in 77! It was quite a mess but, cheap as a result. It was an interesting board. Allison

26 years, 11 months

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Also Available: RL02 Packs

by mcquiggi＠sfu.ca

Hi Gang: I also have about ten extra RL02 packs, if anyone needs any. They even have possibly useful stuff on them, e.g. VMS 5.2, VAX diagnostics, RT-11. Kevin --- Kevin McQuiggin VE7ZD mcquiggi(a)sfu.ca

26 years, 11 months

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Surplus Stuff Available

by mcquiggi＠sfu.ca

Here's a repost of some of my stuff that is still available. Please help me reclaim some space in the basement! > Hi Group: > > Time for mid-summer cleaning. My logjam is getting far too big, and I need > to get rid of a bunch of stuff. > > I am located in Vancouver, BC. Most of this stuff is large and/or heavy, > and therefore I will insist on pickup, or at least reasonable delivery > distance, say, within a couple of hundred miles. > > Some items/systems, such as the pdp-11/60, are at a friend's house, and your > only option in this case, is to pick up. I will not ship 600+ lbs of gear > anywhere! > > Please contact me via email (mcquiggi(a)remove-spamblock.sfu.ca) if you're > interested. I need to clear some space in the basement! > > Here's the list: > > 1. Motorola 6800 development system. EXORcisor system unit, EXORdisk, > non-working SOROC dumb terminal. All manuals, some development boards, > some wirewrap boards. Circa 1975, a neat machine for those into early-PC. > > 2. Terminal, Tektronix 4017A, 16 colors, keyboard with pre-mouse rocker > pointer. All docs, working. Late 1970s, early 80s vintage. > > 3. Sun 3/60 system unit, ~150 MB HD and tape. Mono Sony monitor, keyboard, > no mouse. > > 4. Two Gandalf LDS140 low speed point-to-point modems. > > 5. MicroVAX 3100 model 10, 100 MB HD. > > 6. Boxes and boxes of 5.25" DSDD floppies. > > 7. TK50 tape drives, several, working condition. > > 8. Two BA23 MicroVAX/LSI-11 cases, no machine, just the plastic shell that > the machine fits into. > > 9. pdp-11/60 computer system, several terminals, printers, disk drives, many > disk packs, tape drive (9 track 6250 bpi), software, documentation. Was > working before being put into dry storage a couple of years ago. This is a > _large_ system, main cabinet about the size of 2 full-size refrigerators, > total lot probably 1000 lbs. You'll need a truck! Kevin --- Kevin McQuiggin VE7ZD mcquiggi(a)sfu.ca

26 years, 11 months

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Check out my eBay auctions. Please?

by tcotrel＠pacbell.net

I have just listed the following three vintage computers (classic IBM XT, Osborn Executive and Zenith Data Systems Supersport laptop) for sale on eBay:: http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=140038500 http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=140034810 http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=140032003 Thank you for your consideration Tom Cotrel

26 years, 11 months

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PDP C compiler source code posted...old news?

by af-list＠lafleur.wfi-inc.com

Hi all, Apologies if this is old news to everyone, but the source code for the original PDP C compiler has been posted by Dennis Ritchie, along with a little history. http://www.cs.bell-labs.com/~dmr/primevalC.html Aaron

26 years, 11 months

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PDP CDROMS

by jpl15＠netcom.com

Count me in as a confirmed purchaser of the SigTape CDRs.. Very nice Idea. Cheers John

26 years, 11 months

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floppy disk drive manuals

by edick＠idcomm.com

Figuring out the test points won't be a problem since they use a '3470, which is also used in the Siemens drives. I doubt there's much difference in the circuitry. Oddly enough, I have two of the Tandon drives and no manuals, and none of the Shugart "half-height" drives and both of their manuals. What really troubles me is that after rejumpering the drives to match the data kindly provided by Don Maslin, the two drives behave somewhat differently, though they do now read one another's writing. What's more, the jumpers on the drives, though the drives are the same, don't match Don's data completely. There are jumpers not on the drives which are on the list, and jumpers not on the list which are on the drives. Examined in detail, the drives appear the same, though the boards are of different revision. Perhaps the code in the on-board processor is different. Dick -----Original Message----- From: Tony Duell <ard(a)p850ug1.demon.co.uk> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Saturday, July 31, 1999 12:38 PM Subject: Re: floppy disk drive manuals >> >> Greetings! >> >> I have a couple of Tandon 8" slimline drives (They're in the basement and >> I'm not so no model number.) They clearly can't read one another's writing >> consistently, so I'm interested in alignment data as well as the jumper >> definitions. Would you have a manual which contains that information? I >> need to know what the jumpers are and do, and what the factory default >> settings are. I also need to know where the dif-amp outputs to be used for >> alignment are located, (pin numbers) as well as the index sensor pin and >> other signals used in adjusting these drives for radial head alignment, >> index alignment, track zero calibration, etc. If you have it and could >> email me that data, it would help greatly. > >I know _I_ don't have that info, but that doesn't mean we can't make some >sensible attempts to align them. I have the SA800 and SA850 manuals to >hand, and I may have a couple of obscure 8" drive manuals somewhere. >Nothing Tandon, though. > >You can always use the interface connector as a source of the Index >signal. And of course to move the head around. > >So the only thing you're missing is the output of the read amplifier. If >the read circuitry is in a custom chip you might be out of luck. But a >lot of drives use 592 or 733 amplifier chips at the start of the read >chain, whereupon you look at the outpus (7 and 8) of that chip with a >'scope. If there's an MC3470 as the only chip in the read chain, look for >testpoints in the filter network connected to pins 14,15,16,17. > >If it's a custom chip, look for 2 testpoints and ground (often, but not >always TP1-TP3 in some order) connected to a symmetrical filter network >hung off the chip, Look for read-type waveforms when reading a disk that >was written in that drive. > >-tony

26 years, 11 months

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32 sector 8" floppies

by edick＠idcomm.com

I had the impression that some of the Tektronix systems some of the guys have on hand use 32-sector hard-secdtored diskettes and TEKDOS, hence, the assumption (mine and apparently a weak one) that someone would have a system which could read these. Under no circumstances would I recommend trying to put together a controller, as you've clearly stated the case against hard sectored formats. It's too bad that people who might otherwise have maintained these things have ditched them just because of the odd media, though. Because this is a complete dead-end without some form of conversion, there'll be more of these systems going to the landfill. Dick -----Original Message----- From: Don Maslin <donm(a)cts.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Saturday, July 31, 1999 12:48 PM Subject: Re: 32 sector 8" floppies >On Sat, 31 Jul 1999, Richard Erlacher wrote: Actually, I didn't. This appears to be some of Don M's prose. > >It is a tough one, Dick. In dialogue with Chuck Guzis of Sydex some time >back he observed that there have been so many individual version of hard >sector formats that it would be quite difficult to make up a controller >and software that could read many of them. Similarly, making one for each >case as it came along would also be somewhat prohibitive. > >I think, obviously, that if one knew the details of the format the >challenge would be made less. > - don > >> Oddly enough, I've got nothing (controller) that will read hard sectored >> diskettes. That's probably your reason as well. With all the other fellows >> out there who collect classic hardware, surely there's someone who could >> read these and reduce the source files to a common distribution medium, e.g. >> MSDOS 1.44 MB floppies, for you. >> >> Dick >> -----Original Message----- >> From: Joe <rigdonj(a)intellistar.net> >> To: Discussion re-collecting of classic computers >> <classiccmp(a)u.washington.edu> >> Date: Saturday, July 31, 1999 8:27 AM >> Subject: Re: 32 sector 8" floppies >> >> >> >At 08:41 AM 7/30/99 -0600, Richard wrote: >> >> >> >>SInce this stuff is source code, if you have the ability to read it with >> one >> >>or another ancient system, it might be well to look at the source files to >> >>see what kind of FDC was supposed to be used. >> > >> > I don't have anything that will read them. I tried them on a Compupro >> >but it puked bits all over the place! If you want to give it a shot I'll >> >send them to you. >> > >> > Joe >> > >> >> > >

26 years, 11 months

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paging Anthony Clifton

by fauradon＠mn.mediaone.net

Hi, If anyone has the e-mail addres for Anthony please send it to me I need to get in touch with him and I've lost his address. Thanks Francois

26 years, 11 months

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32 sector 8" floppies

by edick＠idcomm.com

Oddly enough, I've got nothing (controller) that will read hard sectored diskettes. That's probably your reason as well. With all the other fellows out there who collect classic hardware, surely there's someone who could read these and reduce the source files to a common distribution medium, e.g. MSDOS 1.44 MB floppies, for you. Dick -----Original Message----- From: Joe <rigdonj(a)intellistar.net> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Saturday, July 31, 1999 8:27 AM Subject: Re: 32 sector 8" floppies >At 08:41 AM 7/30/99 -0600, Richard wrote: >> >>SInce this stuff is source code, if you have the ability to read it with one >>or another ancient system, it might be well to look at the source files to >>see what kind of FDC was supposed to be used. > > I don't have anything that will read them. I tried them on a Compupro >but it puked bits all over the place! If you want to give it a shot I'll >send them to you. > > Joe >

26 years, 11 months

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Cromemco 4FDC, How do you format a disk?

by allisonp＠world.std.com

<3.5" drives and (most) 5.25" drives use the same data rates. Now <admittedly most 3.5" drives are used at double density, but I really Wrong. The upper rate for 5.25 drive is 250kbit/S (DD) (1.2mb drives are special case). The lower limit for 5.25 drives is 125kbits/S (SD). the 8" are 250 (SD) and 500Kbits/S (dd). 3.5" drives accoring to the sony doc infront of me are 250kbits/S (DD) (720k) and 500kbit/S (1.44) (DD). The 1771 only does the 250kbits/S rate for 8" SD and the 5.25 floppy rate is 125kbits/S. I've tried the SD mode to 3.5" floppies and it's sorta useable but when you figure it out you don't get much for the effort and most of the 1771 based controllers do not deliver or check two sided signals. I have two and they don't! <can't see a good reason why you can't format a 3.5" disk single-density, <using the same data rate as for 5.25" single density disks, which the <1771 is quite capable of. It's half the pulse rate the drive read elctronics are designed to bandpass. <The actual pulse rate at the floppy drive interface is not very different <between single and double density operation. The single-density system <'wastes' half the pulses on clock pulses. Double density is NOT simply True but the peak shift is way different. To get something useful you need to run the 1771 as if it was 8", then use a format that put the right total number of bits on the media roughly 250kbytes a side. then you have an oddball format that noone wants to read (PCs will have fits without a tweeked controller) and will be questionable for the effort. Get a 1793 board and do it right and get some real storage for the effort. The CCS or Compupro boards (others too) are very nice and can be setup so the data rates are appropriate for 3.5" but using the 5.25 connector for the 34pin connector. Don't forget, the step rates for the 1771 class of controllers and drive were also slower than 3MS (more like 12-40ms) so if you going to fix that, the format and what else why not set up a real controller. Either that or learn to fix 8" drives and use them as media is still plentyful. After all I still keep an 8" SSSD format as that is the official CP/M standard. <doubling the read or write clock rate and leaving everything else unchanged Been there done that and have the NEC Tshirt for the 372 sd controller and the 765 all mode. Don't go there. I know the parts and the industry for the time frame very well and have plenty of examples and original docs here to refer too! this is one area where the archive is unusually deep. Allison

26 years, 11 months

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Vintage IBM computer (fwd)

by siconic＠jasmine.psyber.com

Here is someone with an old IBM PC and a Mac+ that needs to find a new home. She is located in California. Please reply directly to the original sender. Reply-to: ccevans(a)telis.org ---------- Forwarded message ---------- Date: Wed, 21 Jul 1999 11:08:23 -0700 From: Carol Evans <ccevans(a)telis.org> To: Sam Ismail <siconic(a)jasmine.psyber.com> Subject: Vintage IBM computer Hi, I have an original IBM 8086 computer with a lot of software from that era to go with it. I hate the thought of taking it to the dump or Goodwill, where it will no doubt also end up there. It works well, but since we upgraded several times, it is unused except for the rare occurance when I want to look up something. I think it should go to a computer museum because it still looks brand new. Have you any suggestions for me? Also I have a 1987 Mac plus, that my daughter took to college with her, then brought home when she graduated to an IBM laptop. I would love to see these go to someone that would appreciate them. Carol in the Redwoods (^..^) purrrrrr........... ccevans(a)telis.org Sellam Alternate e-mail: dastar(a)verio.com ------------------------------------------------------------------------------- Puttin' the smack down on the man! Coming this October 2-3: Vintage Computer Festival 3.0! See http://www.vintage.org/vcf for details [Last web site update: 05/25/99]

26 years, 11 months

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Long-Distance Moving and Storage

by ware＠xtal.pharm.nwu.edu

Due to my recent decision to heed The Call of The Valley, I need to move my collection (about 6000 pounds of equipment) from Chicago to San Jose by the end of next month. I need to thin the herd some before the trip, so I will be posting a message listing available equipment in the near future. Other than the obvious suggestion of moving less gear, does anyone have advice for undertaking such a move? We're thinking of using a professional mover or a "you fill the container, we transport it" type of service if possible, since driving 2200 miles (and over the continental divide) with a 10-month old in a rented truck of questionable mechanical condition seems like a bad idea. The moving companies that I have contacted to obtain estimates have said that the computer equipment is no problem - "just box it up". It sounds easy enough, but I don't know what the reaction will be to 150-pound boxes (or crates) that contain a single item. I'm planning to remove the front panels from the lights-and-switches equipped minis for transport and may remove boards and/or PSUs to lighten individual machines if necessary. Does anyone have other suggestions for dealing with unwieldy items such as rack-mountable equipment and workstation monitors in a long-distance move? -- Scott Ware ware(a)xtal.pharm.nwu.edu

26 years, 11 months

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32 sector 8" floppies

by edick＠idcomm.com

It would be well to remember that, back when hard-sectoring was common, it was considered more efficient than soft-sectoring. Shugart 801 drives were certainly available with hard-sector support as an option. Hard-sectoring did cost more, hence died off quickly enough. SInce this stuff is source code, if you have the ability to read it with one or another ancient system, it might be well to look at the source files to see what kind of FDC was supposed to be used. Dick -----Original Message----- From: Don Maslin <donm(a)cts.com> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Thursday, July 29, 1999 9:44 PM Subject: Re: 32 sector 8" floppies <snip> >> >> Well... I suspect some of the early Tektronix development and perhaps Unix >> based systems, but the MITS Floppy Disk sub-system for the Altair computers >> used them. >> >> -jim > >And various versions of Wang equipment, IIRC. > - don > >> --- >> jimw(a)computergarage.org >> The Computer Garage - http://www.computergarage.org >> Computer Garage Fax - (503) 646-0174 >> >> > >

26 years, 11 months

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Cromemco 4FDC, How do you format a disk?

by allisonp＠world.std.com

<> work. The 5.25" floppy single density rate of 125kBITS/sec clearly would <> fall below the spec. There are limits to the write pulse width as well < <You are still missing the point, totally... < <125kbps FM is _NOT_ 125kpulses/sec at the disk interface, as you seem to <be implying. I'm not missing anything. For FM that means the two frequencies are 125/250KHz. For MFM that is very not true. Different bandwidth, but still not in the range of the accepted 250kbits/sec of the sony. <Double Density, MFM, 250kbps. <----------------------------- <A bit cell is 4us long, so 250000 of them per second. There is a (data) <pulse in the middle of a bit cell written as a '1', no (data) pulse in <the middle of a '0'. There is a (clock) pulse written at the start of a <bit cell if there is no (data) pulse in both this bit cell and the <preceeding one. Your missing bis/time vs frequency domains/bandwith. <For MFM you need to be able to record/reproduce pulses with separations <of 4us, 6us, 8us. true and for the data I gave the 125kbits/sec rate is too low. As it's minima was 250kbits/s is twice that! Part of the recording scheme is that there are rules for continous strings of 1s and 0s, they arent permitted to exist for clocking and bandwidth reasons. <Oh, absolutely. But the FM at half the data rate meets that spec. It has <to. I am not suggesting you could feed 300 baud data into a disk drive <and expect it to work - it almost certainly won't. FM at half the data rate is the 8" SD rate of 250kbits/sec... not 125k! The 125kbits/sec is the 5.25" floppy single denity rate. The problem is that the 2f domain is in the right range but the base rate is clearly not. It's an off by 1/2 problem. The 3.5" drive was designed to reproduce pulses that fall in the 250khz (minima) to 1.0mhz rate(maxima) so theres the bell curve that your skirting using the 5.25" single density data rate. The 8" rate 250kbits/S lands right in the range but rotation time being different you need a different sectoring arrangement. Allison

26 years, 11 months

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New Finds

by jrkeys＠concentric.net

Well this week was not too bad just mostly books and parts. One the books I got at the thrift was Digital Deli written in 1984 and full tips, insights (for the time), and over 115 photos. It's a great read, another I got was a little newer called Computers: Today and Tomorrow and came with a CD, the disk is great. Got a complete set of manuals for the Rainbow 100. Some nice commodore items also like modems and some devices I had never seem before. Will get a list out later. John

26 years, 11 months

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Cromemco 4FDC, How do you format a disk?

by edick＠idcomm.com

There's probably an easier way to look at the issue of data rate versus density on magnetic media. First of all, you must realize that every head/media/rotation-rate combination has a maximal flux reversal density with respect to time. Once you know that, you need merely understand how many flux-reversals the heads must induce on the media in order to record what will be recovered as a single bit. When you look at the manuals which come with various drives and controllers, etc, you get the whole shmear in timing diagrams. Unfortunately, these are marginally misleading. The drive takes the data stream it receives, in most cases, and divides it by two, using the complementary outputs of a flip-flop to drive the circuitry which drives the read/write head. Each time it toggles, it produces, effectively, a single flux reversal on the medium. When the data is read back, it produces a waveform more closely resembling what's in the "books" in that the flux change is "seen" as a pulse by the read/write head. This feeds filters and timing circuits and conditioning circuits which make it into precisely what's expected. However, not all modulation schemes cause the same effect at the head. The FM technique, with a clock always written "on schedule" (except for address marks) and transitions written only for "ones" one can clearly see that FM is an F/2F code, wherein modulation is at one of two rates, either the clock rate, or twice that rate. MFM improves on that by encoding the clock into its data by reversing the flux at more or less the same rate all the time, except that it shifts phase, always positively, in order to avoid exceeding the flux-reversal-density limitations of the head/media combination. (That's the reason the first zero of each string of zeroes is omitted, and that a zero between two ones is not written.) For the reasons above it's not resonable to try to compare FM and MFM. The data rate which has been used with 8" floppy drives has always been (AFAIK) 250 Kbps. The 125 Kbps rate was used with 5.25" floppies, but they came on after the adoption of MFM as the "smart" modulation scheme, so they were normally (except with RADIO SHACK computers) used with MFM. The way in which this modulation technique was applied was not the smartest way in which it could be done, but it did work well, fell well within the limits of the the-available technology, and provided a substantial improvement over what was previously done. The high cost of MFM hardware was what motivated WOZ, at APPLE, to figure out a way to process the data himself into a scheme which used both cheaper hardware and gave, effectively, density equivalent to "double" density, thereby defeating the critics. Dick -----Original Message----- From: Tony Duell <ard(a)p850ug1.demon.co.uk> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Friday, July 30, 1999 4:42 PM Subject: Re: Cromemco 4FDC, How do you format a disk? >> >> < >> <But from my measurements, I think that it's very unlikely that a drive >> <can tell FM from MFM. I will try it sometime to confirm this. >> >> True, but the timing is still important. >> >> The SPEC I have for a Sony MP-F17W-70D (11/1988) makes it pretty clear >> that the acceptable rates are 250/500kBITS/Sec MFM with no discussion >> of plain FM. So it's probable the 8" SD rate of 250kbits/sec would >> work. The 5.25" floppy single density rate of 125kBITS/sec clearly would >> fall below the spec. There are limits to the write pulse width as well > >You are still missing the point, totally... > >125kbps FM is _NOT_ 125kpulses/sec at the disk interface, as you seem to >be implying. > >Let's consider what's actually written on the disk, using standard 5.25" >data rates. > >Single Density, FM, 125 kbps. >----------------------------- >A 'bit cell' is 8us long, so 125000 of them per second. Each bit cell >starts with a (clock) pulse. There will be a (data) pulse in the middle >of the bit cell if the bit is a '1'. > >So, allowable pulse separation times are 4us (between the 2 pulses in the >same bit cell, and between the data pulse in one bit cell and the clock >pulse at the start of the next one) and 8us (between clock pulses if '0's >are written to the disk). > >Double Density, MFM, 250kbps. >----------------------------- >A bit cell is 4us long, so 250000 of them per second. There is a (data) >pulse in the middle of a bit cell written as a '1', no (data) pulse in >the middle of a '0'. There is a (clock) pulse written at the start of a >bit cell if there is no (data) pulse in both this bit cell and the >preceeding one. > >OK, consider some data patterns. Here a ';' singals the start of a new >bit cell, a ',' separates parts of the same bit cell : > >11 -> data pulse, 1/2 bit cell gap; 1/2 bit cell gap, data pulse. Space > between pulses = 4us > >101 -> data pulse, 1/2 bit cell gap; 1 bit cell gap ; 1/2 bit cell gap, >data pulse. Space between pulses = 8us > >1001 -> data pulse, 1/2 bit cell gap; 1 bit cell gap ; clock pulse, 1 bit >cell gap; 1/2 bit cell gap, data pulse. Space between pulses = 6us > >So, > >For FM, you need to be able to record/reproduce pulses with separations >of 4us and 8us. > >For MFM you need to be able to record/reproduce pulses with separations >of 4us, 6us, 8us. > >Since the drive can't tell data pulses from clock pulses, there's no way >it can distinguish continual '1's at FM from the same at MFM, or >continual 0's at FM from 1010... at MFM. Therefore, if it can do MFM >correctly, it can also do FM _at half the user data rate_. > >> Keep in mond most all of the floppies I know of do have a minimum due >> to the read amps bandwidth (there is a banpass filter!) and the > >Oh, absolutely. But the FM at half the data rate meets that spec. It has >to. I am not suggesting you could feed 300 baud data into a disk drive >and expect it to work - it almost certainly won't. > >-tony >

26 years, 11 months

1
0
0 0

Tek 4041

by ccfsm＠ipa.net

Hi All: Does anyone have any information on the Tektronix 4041? I've got a hankering to play with the IEEE-488 bus but can't see paying the current prices that most people seem to want for a IEEE-488 controller for a P.C. I've acquired an Tek 4041 with 512-K and the rom Basic development firmware and even the manuals. But I don't have the (optional) keyboard OR the diagnostics tape. If I could find this tape then I could simple use a RS-232 terminal for program input. I've even got a nice HP 150 that could serve as a terminal, but I need that tape!! Speaking of which, this thing uses a DC100 tape. Know where a soul can find any of these tapes for less that $25.00 each? I know that GP-IB controllers are considered kind of low life - but for some reason I'm hooked on this one (could be the 68008?). Hell, you know what? I'm afraid that old computers are going to be as addicting as old analog synthesizers and Tektronix mainframe o'scopes. Thanks all. Roger Goswick ccfsm(a)ipa.net

26 years, 11 months

3
12
0 0

3Com 3Stations

by jeff.kaneko＠juno.com

Pete: You want some advice, eh? Okay. These beasties support CGA or EGA (you set this up from the setup screen-- No, I don't remember the key sequence, maybe it was CTRL-ALT-ESC, I dunno), and AFAIK, I'm pretty sure they support 1mb simms. (the later models had VGA, and supported more memory). It's a '286 CPU (in case you haven't looked), and while it can't run '386 based stuff, worked fin for most MS-DOS appz. How do you make it boot? Ha. You have to have either: 3Com 3+Start server software, or 3+Open Start (for OS/2 LanMan). 3+Start is a component of 3Com's 3+Share Network OS, and was in direct compettiton with Novell Netware 1.x and 2.x. MS-DOS based networking at it's best, yesindeedy. ;^) Basically, you built a file that was just a bit image of a standard DOS boot disk, with the necessary drivers therein. The START service would then respond to the boot request from the 3Station, effect a network connection, and proceed to serve up the boot volume (volume name setttable via setup, I'm pretty sure). After booting, you would log on to the 3COm network. Pretty slick for 1986, actually. I think I still have all of this stuff somewhere, ifn you want it. The only problem is, you'll need to dedicate a PeeCee just to run the boot services (and whatever other network services you want). An awful lot of work for just a '286, but still fairly cool. You'll also have to dig up a pretty old ethernet adaptor to put in the server. Jeff On Fri, 30 Jul 1999 16:59:52 +0100 "Peter Pachla" <peter.pachla(a)vectrex.freeserve.co.uk> writes: > Hi all, I've had these two "3Com 3Stations" (model 3C1100) lying > around here > for the past 5 years or so and I'd like to actually get them > running. > > Does anyone have any technical details about them; in particular > what sort of > graphics adapter is built in (it looks like either CGA, EGA or > MDA/Herc), what > sizes of 30-pin SIMMs do they take (and how do you set the memory > jumpers) and > how the heck do you get them to boot via the network? > > Anyone able to offer ANY advice? > > > TTFN - Pete. > > -- > Hardware & Software Engineer. Sound Engineer. > Collector of Arcade Machines, Games Consoles & Obsolete Computers > (esp DEC) > > peter.pachla(a)virgin.net | > peter.pachla(a)vectrex.freeserve.co.uk | > peter.pachla(a)wintermute.free-online.co.uk | > www.wintermute.free-online.co.uk > -- > > ___________________________________________________________________ Get the Internet just the way you want it. Free software, free e-mail, and free Internet access for a month! Try Juno Web: http://dl.www.juno.com/dynoget/tagj.

26 years, 11 months

1
0
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Cromemco 4FDC, How do you format a disk?

by allisonp＠world.std.com

< <But from my measurements, I think that it's very unlikely that a drive <can tell FM from MFM. I will try it sometime to confirm this. True, but the timing is still important. The SPEC I have for a Sony MP-F17W-70D (11/1988) makes it pretty clear that the acceptable rates are 250/500kBITS/Sec MFM with no discussion of plain FM. So it's probable the 8" SD rate of 250kbits/sec would work. The 5.25" floppy single density rate of 125kBITS/sec clearly would fall below the spec. There are limits to the write pulse width as well but I'd bet the 1771 meets them as they are fairly narrow range for all data rates and formats. Keep in mond most all of the floppies I know of do have a minimum due to the read amps bandwidth (there is a banpass filter!) and the differentiators used to recover the read data. the head gap width also sets the minimum data rate as well though to a lesser extent. The easiest was to see this is record a track at different rates from 50khz through 1mhz and look at what comes out (or not). Allison

26 years, 11 months

2
1
0 0

RSTS/E <-> RL02 working..

by jpl15＠netcom.com

Well... having sysgenned my 11/44 RSTS/E V9.7 system some time ago to add RL02s (among other things), I have been unable to read/write files to the RL02s, which otherwise appeared normal on the system. (INITable, ERASEable, MOUNTable, etc.) Any and all file operations aborted with a "?Device not available" message. Using the recently acquired RSTS Orange Wall (from Bruce Lane), I have discovered the answer to the problem: one must *create an account* on the device after INITing, etc! [D'Oh!!] Once I did so, the drive assumed it's rightful place in the System and seems to work fine; I copied and erased and re-copied a diskfull of Stuff several times. >>WooHoo!!<< NOW: at one time someone offered me a Bootrom for the RL02s so I can boot the 11/44 from them instead of the (DB0:) Fuji SMD. I need to go back into the mail archives and find that message again, but in the meantime.. I am looking for a 23-751A9 ROM to fit in the M7098 UBI. I will glady pay cloning/shipping/etc for it. Until then I am going to try booting from the RL02 by toggling in the loader code on the Console. But not Tonite! Cheers and thanks to all who offered help/advice!! John

26 years, 11 months

2
1
0 0

32 sector 8" floppies

by edick＠idcomm.com

please see embedded remarks below. Dick -----Original Message----- From: Marvin <marvin(a)rain.org> To: Discussion re-collecting of classic computers <classiccmp(a)u.washington.edu> Date: Friday, July 30, 1999 9:14 AM Subject: Re: 32 sector 8" floppies > >Richard Erlacher wrote: >> >> It would be well to remember that, back when hard-sectoring was common, it >> was considered more efficient than soft-sectoring. Shugart 801 drives were >> certainly available with hard-sector support as an option. Hard-sectoring >> did cost more, hence died off quickly enough. > >Why was hard-sectoring considered more efficient? IIRC, the soft sectored >disks had more capacity than a comparable hard-sectored disk. The overhead for soft-sectoring reduced the number of sectors per track from 32 to 26. This meant that you had (32 * 128 . . . 5 bits + 7 bits . . . 12 bits . . . must be 4K) 4K bytes per track. Anyway, 32 has most often been more than 26 in my book. In some cases not much more, but more, anyway. Drives could be jumpered to increase the sector capacity by skipping sector holes. I was looking at the circuitry just yesterday (in the course of troubleshooting an 8-inch drive) and recall that they allowd for 8 and 16 sectors per track as well, simply by dividing the sector pulses down. This was probably less efficient, due to the decisions made along the way, though it didn't have to be that way. The additional capacity didn't have to be simply doubled just because the number of sectors was halved. I recall something about 8 sectors yielding a capacity of somewhat more than 4K bytes. This does add up, since there are 83,333 nominal bit times per revolution, half of which were used for clock, of course, if FM was the modulation scheme. Since MFM was lurking on the horizon, I guess the LSI makers just decided to forget about hard sectoring. Nobody believed anyone would ever want a floppy diskette format which yielded more than what MFM would offer. It's just like nobody once believed that more than 64Kbytes of memory were desirable in a home computer, right? The difficulty arises from the general discontinuance of the manufacture of the FDC's capable of dealing with hard sectored media. Both NEC and Intel made a version which handled hard sectored media back in '76. It disappeared from their repertoire by '78, though. NEC also made a digital tape cassette controller which went the same way.

26 years, 11 months

2
1
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Fw: RL-01 drives UK

by danburrows＠mindspring.com

26 years, 11 months

1
0
0 0

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