test-drb March 2007

test-drb@ccmp.vtda.org

239 participants
488 discussions

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

17 years, 3 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

17 years, 3 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

17 years, 3 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?

17 years, 3 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

17 years, 3 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

17 years, 3 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

17 years, 3 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

17 years, 3 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

17 years, 3 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

17 years, 3 months

← Newer
1
...
10
11
12
13
14
15
16
...
49
Older →

Jump to page:

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

2001

2000

1999

1998

1997

test-drb March 2007