test-drb

test-drb@ccmp.vtda.org

101090 discussions

by jwest＠classiccmp.org

I was letting the 11/45 instruction excerciser run in a loop just to work the machine while I was digging through the RL02 prints to find all the signals going to the fault lite. Looked over at the machine and it had locked up after running fine for about 5 hours. Wonderful. I figured one of my cpu boards was probably marginal and was preparing to swap boards and then I could swear I heard Tony yelling at me from across the pond. So I got out the scope and started checking the backplane power testpoints. Sure enough, E16B2 and E21B2 are both (basically) zero, and they were NOT that way before when I had a problem with the top 742 supply. Looking through the prints shows they should have been at -15v and come from the bottom 742 built in regulator. ARGH! So now it's the same board in the bottom supply that failed in the top supply a week or two ago. Glad I ordered some extra parts from mouser when the last one died. Further thought and I realized that slots 16 and 21 are for the mos/bipolar memory controllers. I don't have mos/bipolar memory. So I was wondering what else comes off that regulator board on the bottom 742. From recent memory I believe I recall the LTC comes from there. But LTC being fried wouldn't cause the cpu to fail to come up would it? And since I'm not actually using mos/bipolar I'm left wondering what else is coming off that board. AC lo or DC lo signal perhaps? I seem to remember that something odd was done to the regulator board in that lower 742 to make the output -15v instead of 15v like the top 742. In any case, I obviously SHOULD fix the regulator in the bottom 742 so I get that -15v back but I am left curious as to if that is what is causing the cpu to suddenly no longer come up and run. Am I on the right track here? Jay

19 years, 2 months

simple question about turning off/on a regulator.

by jpero＠sympatico.ca

Fixing FE1250 Nec (actually two!), 22" monitor monsters. Have the bulletin on fix these problems and problem is that I cannot get this part easily here. Switchable off and on adjustable regulator set for 3.3V in 5 pin SMD flat pack with heatsink tab. The part number PQ20WZ51, marker: Sharp. I can make a 3.3V regulator but best way to switch it off or on (fet or transistor with low gate/base current? Data sheet for this regulator is available had to dig inside sharp semiconductor area even with google didn't find to find out what I need to rig the power control side. Cheers, Wizard

19 years, 2 months

Source for 1Mx1 DIP DRAM

by aek＠bitsavers.org

> I'm looking for (32) 1Mx1 120ns DRAM chips to populate an Amiga memory > board. http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=140067553378 they are 100 ns

19 years, 2 months

DEC MicroVAX 3800 - still amazes me

by ddsnyder＠zoominternet.net

I have a couple of MicroVAX 3800's that became part of my collection of space heaters during the Y2K period. It amazes me these machines still power up and boot VMS. The date these machines were purchased was sometime in 1989. Both are well equipped and came from a production environment. They gathered process data almost non stop for 10 years. What a perspective correction... I have a C-Itoh CIT-220+ attached to the console port, 12 inch amber screen, no mouse. Pays sometimes to know where we have all been from, makes me feel a bit aged.. Dan @ Butler, PA

19 years, 2 months

baud modifier

by dgriffi＠cs.csubak.edu

I'm thinking of a device that would step down the speed of an rs232 connection from, say, 9600 to 110. The idea is to allow a computer that can't do 110 to talk to an ASR33 teletype. Does such a device exist? What's it really called? Does anyone have any schematics for one? -- David Griffith dgriffi at cs.csubak.edu A: Because it fouls the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail?

19 years, 2 months

Creating an 8-inch floppy from 3.5-inch Teledisk image

by glen.slick＠gmail.com

I finally got an 8-inch floppy drive connected to a PC and now I want to create an 8-inch boot floppy from a Teledisk image I found, but tdcheck says it's an 82 track 3.5-inch floppy image. That's seems odd. http://www.retroarchive.org/cpm/os/ALTOS.ZIP Anyone know for sure if I should be able to use Teledisk to write this image directly to an 8-inch floppy? Or would I need to do something like write the image to a 3.5 inch floppy and then use ImageDisk to read that floppy and write it to the 8-inch floppy? -Glen

19 years, 2 months

Hmm

by stevew＠ka6s.com

> Written by Tom Watson, tsw at johana.com >On Thu, 22 Mar 2007 19:20:51 -0700, "Chuck Guzis" <cclist at sydex.com> wrote: >>> On 22 Mar 2007 at 14:59, Steve Wilson wrote: >>> >>> >4900796 (Somebody will understand this reference) >>> >>> Someone is trying to boot Fortran off of the Disk on an IBM 1620 me thinks >> >> Isn't 00796 where all-well-behaved programs went to die? I.e. reload >> Monitor (sort of a CALL EXIT)? >> >> --Chuck > >We have a winner. >Just to add to the trivia, to boot the disk you needed a few more characters: >3400032007013600032007024902402111963611300102 >Which if you were on a model 2, you needed to make sure that indirect >addressing was turned on (nothing worked right if you didn't!). > >After doing that a few times, you remembered it pretty well. (Stuff deleted) >Tom Watson >tsw at johana.com So Tom, Do I at least get partial credit for knowing it was from the IBM1620? A friend of mine told me that sequence 30 years ago - and along the way I got confused as to the function. (I know - excuses excuses ;-) I can 't explain why I'm carrying around that data in my head either... I only programmed in GoTran twice, i.e. hands-on a 1620 that many times back in the 1970's at Oxy College in Pasadena on the weekends. A high school buddy was the true Guru in 1620 Machine language. As for the IBM1130 - I've only programmed on one of those in Fortran IV once (though my college buddy Bob seems to have one he is trying to ressurect - http://www.dvq.com/1130/1130.htm) Steve Wilson

19 years, 2 months

single transistor projects?

by wbblair3＠yahoo.com

> >When I was a kid I had a book, I think it was called something like > >"single transistor projects". As I recall it was full of lots of > >simple circuits featuring a single transistor. > >(or who knows, maybe it was 101 transistor project; I think I was > >in 4th grade at the time - late '60s) Is this it?: 125 One-Transistor Projects (1970) http://tinyurl.com/2fzqhm ____________________________________________________________________________________ Sucker-punch spam with award-winning protection. Try the free Yahoo! Mail Beta. http://advision.webevents.yahoo.com/mailbeta/features_spam.html

19 years, 2 months

Transistor Projects

by technobug＠comcast.net

The following caught my eye on the back page of a flyer from a remainder bookseller: "Electronics Lab: The Ultimate Electronics Pack" by Brenda Bach. Its a book with a bunch of experiments as well as the components. It originally sold for $20 and they ask $5.95. It's at <http://www.hamiltonbook.com/hamiltonbook.storefront> and is item 6136583. CRC

19 years, 2 months

Tiny BASIC Extended available

by ajp166＠bellatlantic.net

> >Subject: Re: Tiny BASIC Extended available > From: "dwight elvey" <dkelvey at hotmail.com> > Date: Fri, 23 Mar 2007 20:31:51 -0700 > To: cctalk at classiccmp.org > > > > >>From: "Jay West" <jwest at classiccmp.org> >> >>I've been hunting for a Tiny BASIC interpreter for the 6502, written in >>6502 assembler with source. I haven't been able to find such a thing. >>Anyone have one floating around? >> >>Jay >> > > >HI Jay >I thought Tom Pittman's TB was for 6502? ( or maybe 6800?) According to the manual and the article (I have both) it was written for both. I have the 6502 version. It's possible I have a papertape of the 6800 version. >As for TB's that are ROMable, I have PaloAlto Tiny Basic in a 2K >ROM for 8080. It has been enhanced from the version that was >published to include the ability to extend. It currently runs in a >Poly88. I've extended the instructions to do PEEK, POKE and >SAVE. I also have StarTrek that runs under it as well. >I've disassembled it and made a commented listing. Most of the >comments are from the original list with some of the spelling errors >fixed. I've added comments about the extention of commands >but that is easiest understood from my listing of the extentions. > I've sent it to someone that put it on a web page but I don't >recall who or where. >I also have Tom's code as well but didn't finish playing with it >when I found it didn't fit in 2K. It was 2K plus about 20 bytes >as I recall. I'm sure I was intending to use it on my SYM-1 so >it must be 6502. >Dwight There were several that are romable. Also there was LLLBasic (Lawrence Livermore Labs) a 5k basic that was also romable (and available on rom). I have that in hardcopy as part of a Best of Interface Age anthology Volume 1 Software in Basic. That had LLLBASIC for 8080, Dr Wangs Palo Alto TB, National NIBL, and Robert Uiterwyks 4K 6800 basic (floppy rom experiement). I'd be surprized if most of that wasn't already on line somewhere. Allison

19 years, 2 months

Ultrix device names

by dbetz＠xlisper.com

I have a MicroVAX II that is able to boot into Ultrix 4.3 single user mode. If I type "mount" it says that /dev/ra0a is mounted on /. I assume that is my ESDI hard drive since the drives plugged into my SDC-RQD11-EC ESDI controller are the only ones plugged into my system. So, my question is, what would the second drive on that controller be called? Would it be /dev/ra0b or /dev/ra1a? In other words, what do the "0" and "a" parts of the device name mean? Is "0" the controller and "a" the device on that controller? I also have a TD Systems Viking SCSI controller in the system with a CD-ROM drive attached. What device name would I use for that? I'd also like to know how to address that drive from the MVII boot prompt so that I can boot directly off of the CD-ROM. Thanks, David

19 years, 3 months

Creating an 8-inch floppy from 3.5-inch Teledisk image

by g-wright＠att.net

-------------- Original message from "Glen Slick" <glen.slick at gmail.com>: -------------- > On 3/23/07, Richard Lynch wrote: > > > > I ran into this file a few years back and wasn't able to do much with it. I > > later created my own Altos floppy images using both Teledisk and Imagedisk. > > I'll send them to you offlist for you to try out. > > Richard Lynch > > > > I have an ACS8000-7 dual floppy and an ASC8000-10 floppy / hard drive. > > On both of them I get the monitor prompt to insert a floppy for > autoboot (the -10 fails the hard drive boot first). I tried creating > floppies from ACSBTMD1.IMD and DIAG26K.IMD and I don't get any > indication that anything is happening on either system with either > floppy. No additional output on the terminal and it doesn't appear > that the floppy is seeking at all. > > I don't know for certain that the floppy drives are actually working > on either system other than the motors running. I got them as-is a > couple of years ago with no boot floppies and no way to create boot > floppies at the time. > > I suppose I could pull the drives and attach them to the PC I used to > write the floppies and see if I can read the floppies back ok. That > sounds too much work like work instead of fun for this evening. > > -Glen Glen I have both of theses and you should hear the drives load and unload the heads. . One of the problems I have is the head (nut and screw) assembly stick and the head never gets back to track 0. I have also had to replace the floppy disk controller chip in my 8000/2 in the past These use different boot disks. I have both if you need another sorce. No too sure what is in the ZIP file. - Jerry

19 years, 3 months

IBM PS/2 Models 25 and 30

by ddsnyder＠zoominternet.net

To all who replied, good point, when offering a machine, state the processor manufacturer, number and speed. I'll eventually develope a system... Model 30 is an Intel (AMD) 80286 at 10Mhz Model 25 is an Intel (NEC) 8086 at 8MHz Dan @ Butler, PA

19 years, 3 months

Byte magazine back issues

by jwstephens＠msm.umr.edu

are the byte magazines available online anywhere, including scans of advertisements? I am interested in some ACP ads, but don't know when they were placed. anyone with a collection I would appreciate finding the full page rear cover inside or outside ads, and getting a high res scan. thanks Jim

19 years, 3 months

John Backus passes away...

by roger.holmes＠microspot.co.uk

>>> 100 FORMAT( HX)=(1+BX ) >>> >>> Recall, that prior to FORTRAN 90, FORTRAN had no reserved words. >> >> Yes that does look weird at first sight. > > The bigger problem is that it's absolutely ambiguous in the light of > CDC FTN syntax. It can legitimately mean either a FORMAT statement > with the Hollerith constant ")=)1+B" or an assignment to the HX-th > element of an array called FORMAT of the value obtained by evaluating > 1+BX. The PTR ended up on the "deferred" list for quite a long time > as no one could think of an adequately airtight fix. Lots of work- > arounds were proposed, such as "well, if the statement number is > referenced in an I/O statement, then it's a FORMAT" or "if there's an > array called FORMAT, then it's an assignment". Unfortunately, > FORTRAN doesn't demand that FORMAT statements be referenced by an I/O > statement--"orphans" are perfectly legal. It was a real puzzle. Thanks for that, I had completely missed what you were saying, though I still don't know what a PTR is, except for a Paper Tape Reader or an abbreviation for PoinTeR. A bug report? If a FORMAT statement is not referenced by a READ or WRITE statement, does it matter if it is compiled incorrectly? Anyway, if they wanted an assign 1+BX, why put it in parentheses? Still an interesting example though. > Smart*ss customers! > > The usual way for FORTRAN compilers to work back then was to look at > the first word of a statement and attempt to parse it accordingly. > If that failed, then the statement was deemed to be an expression and > re-parsed. I presume that's why some Basics needed LET before an assignment. > This is only one case where a vendor's language extension got it into > trouble. Early on, most language standard specifications called out > the minimum subset of the language that had to be implemented and > remained silent on vendor extensions. Hence, you got scads of > differing dialects all claiming to be "FORTRAN IV". To my knowledge, > this persists in BASIC more than in any other language, ANSI X3.113 > nothwithstanding. Human languages are far worse of course. Roger.

19 years, 3 months

Long Paper Tape (renamed)

by roger.holmes＠microspot.co.uk

> From: woodelf <bfranchuk at jetnet.ab.ca> > >> Later on we moved the compiler onto a GEC 4080 to cross compile >> for the >> 920. The 920 program grew and I had to modify the compiler so it >> could >> produce the binary output in chunks as it exceeded a 1000 foot >> roll of >> tape, and anyway I was the only person in the office capable of >> rolling >> up a full 1000 foot roll without damaging it. > > I am guessing you get 8 characters per inch of tape. > That is a 93.75 K of data per tape. Ten characters per inch, so 120KB. Useful content though was one 18 bit word per three characters, so 40K words. The 920ATC had 128K words of program/data storage plus another 128K for data only. So if every instruction was used, that's 3 full reels of tape and possibly more if there were any pre-loaded tables in the data only section. The reason it was difficult to wind up was our paper tape winders only had a 6 of 7 inch back plate, so beyond that I had to use two fingers to guide both sides of the tape, and got hard skin on both fingers. It became such a problem the company bought Penny & Giles 1/4 inch cassette tape machines. They worked fine for a while then the baud rate started drifting as it was derived from an RC network! Eventually our engineers modified them to use a proper oscillator circuit. In the mean time I had hooked up a direct serial link between the 4080 and the 920ATC running at 9600 baud. My first comms program (well, sort of). Roger.

19 years, 3 months

Hmm -

by sdc695＠yahoo.com

On Thu, 22 Mar 2007 19:20:51 -0700, "Chuck Guzis" <cclist at sydex.com> wrote: > On 22 Mar 2007 at 14:59, Steve Wilson wrote: > > > >4900796 (Somebody will understand this reference) > > > > Someone is trying to boot Fortran off of the Disk on an IBM 1620 me thinks... > > Isn't 00796 where all-well-behaved programs went to die? I.e. reload > Monitor (sort of a CALL EXIT)? > > --Chuck We have a winner. Just to add to the trivia, to boot the disk you needed a few more characters: 3400032007013600032007024902402111963611300102 Which if you were on a model 2, you needed to make sure that indirect addressing was turned on (nothing worked right if you didn't!). After doing that a few times, you remembered it pretty well. OB Fortran reference: There were several "load & go" Fortrans available for the 1620. The one I liked the best was Witran. It fit into a 20k machine, but was interpreted. Still not too bad for a Fortran. The best was the Monitor II Fortran II. It generated automatic floating point instructions, and used index registers (only for the compiler I think). Pretty speedy. The hardware floating point on a 1620-II was faster than the software on the (next generation) IBM 1130 (I used that too). The 1620's bonus was that standard precision (in floating point) was 8 significant digits. If you really felt ambitious, you could go MUCH higher (28 digits with Fortran-II). Few machines today can match that in hardware! -- Tom Watson tsw at johana.com ____________________________________________________________________________________ Get your own web address. Have a HUGE year through Yahoo! Small Business. http://smallbusiness.yahoo.com/domains/?p=BESTDEAL

19 years, 3 months

John Backus passes away...

by Billy.Pettit＠wdc.com

* Al Kossow wrote: > I wonder which machine would take the prize for the > most done with so little? In the 60's, probably the LINC 1 or 2k 12 bit words, LINCtape, typewriter, CRT, and Lab I/O http://www.mit.edu:8001/people/ijs/epl/LINC.html Billy: It touched me as a little ironic that the photo attached said: JPEG image, 20k Linc could so much with 1 or 2K, and today we need 20K just for a simple photo of it. Billy

19 years, 3 months

John Backus passes away...

by ken＠seefried.com

From: Sridhar Ayengar <ploopster at gmail.com> >Jules Richardson wrote: >> > I wonder which machine would take the prize for the >> > most done with so little? > >I would have guessed something with plugboards for programming. >Possibly drum-memory. > Bletchley Bomb and/or Colossus? Certainly the results to resources ratio was pretty amazingly high.

19 years, 3 months

One last comment on Burroughs and crossbar switches

by aek＠bitsavers.org

A little more digging, and the crossbar in the B 5000 series idea came from the D 825 SAGE backup system AN/GSA-51 ref. Burroughs B 5000 conference Sep 85, archived by CBI (page 18) other references can be found on line to the D 825 being the first multiprocessor, and to the memory/processor switch http://www.cs.uiowa.edu/~jones/arch/notes/35cross.html http://www.fas.org/nuke/guide/usa/airdef/buic.htm http://www.cc.gatech.edu/gvu/people/randy.carpenter/folklore/v3n1.html

19 years, 3 months

Can the MicroVAX II or KDJ11-A boot off of a SCSI CD-ROM?

by dbetz＠xlisper.com

It seems all of my removable media devices are broken (TK50 and RX50). That leaves me wondering if I can boot a MicroVAX II or a KDJ11-A off of a CD-ROM. I have a SCSI controller that should work with either machine and I have a SCSI CD-ROM drive. Can either of these machines boot from a SCSI CD-ROM? Thanks, David

19 years, 3 months

OT: SPAM Spoofing

by healyzh＠aracnet.com

I've got a problem, and am wondering if anyone has any advice as to what I can do. I run my own private mailserver on my OpenVMS 7.3-2 system. Only a few people know how to get ahold of me, and it's basically used to communicate with my family. Someone started sending out spam yesterday that appears to be coming from my IP address and domain name based on the email headers, yet I've verfied the messages aren't originating from my network. As a result of this my VMS server has been thrashing, the B******* are using a fake account name that is 14 characters long, so OpenVMS won't automatically reject it, but instead bounces the bounces, then accepts the bounce backs. Last night I finally shut down SMTP on my VMS server, and am blocking all incoming SMTP connections at my firewall. I've also alerted my ISP as to the problem. Is there anything I can do about this? My one thought is to do an "emergency" upgrade to OpenVMS V8.3 as it will reject email to invalid accounts that are 13+ characters in length, and then turn SMTP back on. I've been meaning to do the upgrade, but haven't had time yet. Zane

19 years, 3 months

Why blinkenlights ?

by jos.dreesen＠bluewin.ch

I am currenly contemplating what kind of IO to put on my coming i8008 system : what is it that makes blinkenlights (i.e. leds and switches ) seem so attractive ? It must be about the worst possible way to interact with a computer... So why is it then that almost all early micros had them ? a 7segment display with keyboard ( as in a H8) is clearly more usable, and would have cost nothing more. Or were early eproms (for the monitor program) that expensive ? Jos

19 years, 3 months

Tiny BASIC Extended available

by eds_2＠yahoo.com

Every so often, a discussion of Tiny BASIC appears around here. I was curious about one of the very first versions of Tiny BASIC, the 8080 implementation done by Whipple and Arnold, as documented in the Vol. 1 No. 1 (Jan 1976) issue of Dr. Dobb's Journal (of Tiny BASIC Calisthenics and Orthodontia) This issue contains an octal listing of a Tiny BASIC interpreter for the 8080, and I couldn't find this version available for download anywhere. So... I typed it in, and it works! I documented my work, which is available at http://oss.readytalk.com/tb/tinybasic.tar.gz (Note - this location is temporary - I need a home for this if anyone is interested) Included are the text file for the octal listing, a binary which can be loaded into memory, an attempt to extract the IL from the binary, and some instructions on bringing up Tiny BASIC. I was able to run some simple programs with a Z80 simulator that I've been running, and it appears to work correctly. I found the PDF of the listing in the ACM digital library: http://doi.acm.org/10.1145/987491.987494 Typing in octal listings is error-prone enough, and typing them in from bad PDF scans of bad photocopies is even trickier. I have corrected many errors, but I'm sure there are more. If any kind soul would be willing to proofread / correct the listing, it would be **GREATLY** appreciated. I hope this is of interest to people. I'm very interested in other versions of Tiny BASIC out there, if someone has ever typed this listing before, etc. I'm familiar with Tom Pittman's work, but other resources would be greatly appreciated. -Eric ____________________________________________________________________________________ 8:00? 8:25? 8:40? Find a flick in no time with the Yahoo! Search movie showtime shortcut. http://tools.search.yahoo.com/shortcuts/#news

19 years, 3 months

Tiny BASIC Extended available

by ajp166＠bellatlantic.net

> >Subject: Re: Tiny BASIC Extended available > From: cctech at porky.vax-11.org > Date: Fri, 23 Mar 2007 08:32:28 -0600 (MDT) > To: "General Discussion: On-Topic Posts Only" <cctech at classiccmp.org> > > >Would enhanced basic work? > >http://members.lycos.co.uk/leeedavison/6502/ehbasic/index.html > >Clint > >On Thu, 22 Mar 2007, Jay West wrote: > >> I've been hunting for a Tiny BASIC interpreter for the 6502, written in 6502 >> assembler with source. I haven't been able to find such a thing. Anyone have >> one floating around? >> >> Jay >> >> I have Tom Pitmans Tinybasic for 6502 is that what you want? If so email me direct for a copy. Allison

19 years, 3 months

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test-drb