test-drb December 2014

test-drb@ccmp.vtda.org

179 participants
207 discussions

Defeated by a Commodore 1950 Monitor

by nf6x＠nf6x.net

I have a Commodore 1950 monitor that came along with an Amiga 3000, and I think it has defeated me. Its failure mode is that there's no vertical scan; just a single, horizontal line. Vertical drive is still working, because I can shift the line up and down a bit using the vertical centering control, but whatever circuitry generates the vertical scan doesn't appear to be doing it. Trying to debug it has been challenging, even though I found a service manual online. The monitor appears to have been designed to be slapped together without much consideration of service accessibility, and the service manual does't describe the circuitry in much detail. It includes a block diagram, with no indication of which actual circuitry corresponds to which blocks. The schematic diagrams show connectivity between the parts, but don't identify the functionality of most of the ICs. I think I've narrowed down to one IC that's a likely candidate for the failed component, but it's still just an educated guess that it's even the IC responsible for generating the vertical scan. And it's a no-name IC with the monitor manufacturer's internal part number (IC401, with part number 56A326-1), so I don't think I'm likely to find a replacement for it unless I find another model 1950 with a different failure. I have an LCD monitor that I can use with the A3000, but the A3000 just doesn't look right with a flat panel on top of it. Now I wish I hadn't gotten rid of my old Viewsonic 17" CRT monitor all those years ago! I was sure happy to see it go at the time, but I failed to predict that I'd get interested in retrocomputing a decade later. So, I guess I'll just keep my eyes open for a suitable CRT monitor that I like for the A3000. Maybe some older Viewsonic monitor in the 13"-17" range? If anybody near southern California might be able to use my failed 1950 for parts, or has a 1950 with a different failure that they'd like to dump on me, please let me know! Even though I don't anticipate being able to fix it, I don't want to throw it away, in case parts appear or some other collector can make use of it. So, I'll stash its carcass away for the time being. -- Mark J. Blair, NF6X <nf6x at nf6x.net> http://www.nf6x.net/

9 years, 7 months

Weird 8-inch floppy disk

by dgriffi＠cs.csubak.edu

I found a ten-pack of 8-inch floppy disks that have me confused. They're >from STAM@, a name I've never heard of before. It's clear that they're hard-sectored, but the index and sector holes are along the outer edge. There's also a notch cut into the corner. Both of these appear to be done in an attempt to restrict users to a single vendor of floppies. Here are some pics: http://661.org/images/weird-floppy-front.jpg http://661.org/images/weird-floppy-back.jpg -- 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?

9 years, 7 months

Whitechapel Computer Works MG-1

by axelsson＠acc.umu.se

Hi! I just got the "Owner Operator Guide" manual for a MG-1 from a friend. I did some searches and found a picture on wikipedia in the article about Whitechapel Computer Works. ( https://en.wikipedia.org/wiki/Whitechapel_Computer_Works ) I also found an evaluation of the MG-1 and several contemporary workstations... http://www.chilton-computing.org.uk/acd/sus/perq_papers/perq_external/p003.… ... but then I drew a blank. It seems like these are really rare systems. Does anyone have a system? Anyone need the manual? The system could still be around so I'm going to dig around at the university a while to see if I can locate it. If Al wants a copy for bitsavers I'll scan it before letting it go. G?ran

9 years, 7 months

3M "WhisperPrinter" (Trendcom 100) docs?

by derschjo＠gmail.com

Picked this up for nearly nothing at a local recycler, it was too cute to pass up. It's a 3M "WhisperPrinter" (model 1904AA), and it's a small (40 column, 4.5" wide) thermal printer with a serial interface. It appears to work (runs a self-test if you hold the line feed button while powering on) but I don't know what the pinout for the interface on the rear is (it's a 20-pin header). This looks to be a rebadged Trendcom 100 (which I can also find very little technical info about) used on a number of early home computers (Atari, TRS-80, PET). Anyone happen to have a manual for this? Thanks, Josh

9 years, 7 months

Summary: is there any word processing software for the pdp11?

by jacob.ritorto＠gmail.com

I was seeking the "best" pdp11 prose text editing experience for typing in manuscripts, composing, letter writing, etc. (not programming language - that was just a side effect of some editors actually being programming languages in and of themselves). Since this is such a highly relative subject, I expected a slew of answers and got them (thanks, all!). While not part of the originally-intended scope, the conversation has inspired me to at least try composing in TeX, which I've sort of meant to do for years, but never got a round tuit. Sounds like it'll stay out of my way and allow me to just flow ideas and not even address layout until the end, which is, in essence, what I'm after. That said, I think the most convincing answer to my original question so far, not having actually reviewed them yet, is some kind of emacs, most likely Jove since it's already there in 2.xBSD and keeps me from having to mess with/re-learn other operating systems (oh, shoot!). As a side note, I used teco and edt back when pdp11s running DEC operating systems were still being phased out and found them to be unsatisfying; however, I do admit that I was an amateur at them. My other point here was to get the Diablo 630 going and have it type nice, letter-quality copy for me. Since my kid had a report due this morning, I caved and temporarily connected it to an old Sun machine and just threw lpd at it. Pretty straightforward: lpadmin -p diablo -v /dev/cua/b -o stty=300 -o banner=never enable diablo accept diablo So the thing's up and accepting jobs. Prints like a war zone :) !!! Once one of the '11s is up, on the net and stabilized, I'd like to have it take over this role as well. thx again for all the discussion around this & feel welcome to continue the thread! jake

9 years, 7 months

List memberships and duplicates [was Re: Yay, now I need some Osborne boot media!]

by jnc＠mercury.lcs.mit.edu

> From: Peter Coghlan > 2) All cctech subscribers are experiencing it and very few find it a > problem. > or > 2) All cctech subscribers are experiencing it and there are very few > people subscribed to cctech! I rather suspect it's 2B... :-) > So, I subscribed to cctalk (with the same address I use for cctech > which on reflection may not have been a good idea) I think you've hit the nail on the head... > However, I have not started getting three copies of anything. > Everything is very much as before, one copy from from cctalk and > usually another some time later from cctech Possibly what's going on is that Mailman has noticed that it's trying to send that email address _two_ 'CCTalk' copies: one for your actual CCTalk subscription, and one for your pseudo-subscription (via CCTech). It thereupon automagically suppresses the second copy. > So what next? I get the feeling that if I unsubscribe from cctech, I > will stop receiving anything at all Nope, my guess is you'd wind up with one copy (from your 'real' CCTalk subscription). Go ahead and try it: you can make sure you don't miss anything by looking in the archive (which is how I read the list: I don't actually get _any_ copies... :-) Noel

9 years, 7 months

Tandon TM-848E Normal Behavior?

by cctalk＠fahimi.net

Does anybody know if it is normal for a TM-848E to spin up for a few seconds after getting power and then stop spinning. The only other 8" drives I have experience with seem to start spinning when power is applied and keep spinning regardless of if the door is latched or if there is a disk in there. Thanks.

9 years, 7 months

Nat Semi ns32k, was Re: Whitechapel Computer Works MG-1

by jnc＠mercury.lcs.mit.edu

> From: Steven M Jones > only to be pummeled by the emerging RISC designs... My (dim) recollection of the NS32K architecture (I recall someone came to MIT and gave a presentation on it, and I have an early architecture document - so old that it's called the NS16K!) was that it was very elegant, but my sense now, looking back, was that it was one of that wave of machines (the VAX being the other notable one) that went down the CISC road just before RISC arrived, and showed that CISC was not really the way to go; those systems were all dinosaurs. Which, in the NS16K/NS32K's case was unfortunate, because the architecture in other ways, i.e. at a high level (i.e. ignoring the instructions), was the best of the whole lot. Notably, it attempted to provide real segmentation support, perhaps the only chip of that group to do so. Although of course once Unix took over the world, that was irrelevant. (Much as I dearly love(d) V6 for how it got an incredible amount of power out of a very small machine, it's pretty clear that the basic approach of Unix was inferior to that of the single level store systems [e.g. Multics]; Unix really was - and in many ways remains - a toy operating system, considered >from a larger viewpoint.) Noel

9 years, 7 months

rain.c

by jacob.ritorto＠gmail.com

setbuf((&__iob[1]),malloc(1024)); if (!(term=getenv("TERM"))) { On Tue, Dec 2, 2014 at 1:22 PM, Holm Tiffe <holm at freibergnet.de> wrote: > Jacob Ritorto wrote: > > > Given the gloomy weather and speaking of porting, I just got bored and > > tried to compile /usr/src/games/rain.c from 2.11bsd on opensolaris using > > gcc3.44. It errored out with rain.c:61: error: parse error before '->' > > token. What's that all about? There's not even a pointer on that line: > > 61 float cols, lines; > > > > rain.c source here: > http://www.retro11.de/ouxr/211bsd/usr/src/games/rain.c > > > > Tell us what you see when you use the C-preprocessor only on that file: > > gcc -E rain.c |less > > and then search in the output for setbuf: > > > float cols, lines; > > setbuf(__stdoutp,malloc(1024)); > if (!(term=getenv("TERM"))) { > > > ..like this. > > This is FreeBSD here and you can see that setbuf handles a pointer.. > > Regards, > > Holm > -- > Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, > Freiberger Stra?e 42, 09600 Obersch?na, USt-Id: DE253710583 > www.tsht.de, info at tsht.de, Fax +49 3731 74200, Mobil: 0172 8790 741 > >

9 years, 7 months

Somebody in Portland should save this...

by wh.sudbrink＠verizon.net

Ohio Scientific business unit: http://portland.craigslist.org/mlt/ele/4776461141.html

9 years, 7 months

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 December 2014