test-drb October 2005

test-drb@ccmp.vtda.org

264 participants
655 discussions

by ajp166＠bellatlantic.net

> >Subject: Re: Character Generator ROM data > From: woodelf <bfranchuk at jetnet.ab.ca> > Date: Sat, 22 Oct 2005 11:03:04 -0600 > To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> > >Drat I just threw out that data. Well not the ROM data but the manual >for a video display >that had the character set. Remember the roms used desenders so it was >more like 8x12?. I'm sure the VT100 series manuals are on line somewere. Other manuals that have that data was the Processor Tech VDM-1. Allison

19 years, 2 months

Calling Mike Stein...

by dm561＠torfree.net

ISP's been down a few times; anyone else having trouble or waiting for a reply from me, pse try again. tnx, m ------------------------------- Date: Sat, 22 Oct 2005 14:14:09 -0500 From: gtulloch at shaw.ca Subject: Calling Mike Stein... Mike Stein, drop me a note, none of your email addresses work anymore :) Regards, Gord

19 years, 2 months

Any own an 11/725...?

by ethan.dicks＠gmail.com

On 10/23/05, Zane H. Healy <healyzh at aracnet.com> wrote: > How hard would it be to get a Unibus working in a VAX-11/725? I > doubt I'll *ever* manage to get one, but if I did, I'd much rather > switch it to SCSI than have to deal with the RC25. Hard? Not hard at all - yank the KLESI-U and drop in a Unibus SCSI card. I happen to _have the RC25 on it, and as has come up before, I've personally never had a problem with them (I should most likely add 'yet'). Of course, I have plenty of smallish SCSI drives that would be perfect, but unless I could find a reasonable deal on a controller, I'll just stick with DEC stuff for now. -ethan

19 years, 2 months

Short review of $550 power cord plus a new SWTPC 6800

by CCTalk＠catcorner.org

> From: Chuck Guzis [mailto:cclist at sydex.com] > Sent: Saturday, October 22, 2005 3:40 PM > > This whole business reminds me of an old scifi short story > where a fellow > wakes up 100 years in the future and finds that car > speedometers go to 350 > mph--but start somewhere around 200 at a dead stop. > > Cheers, > Chuck > Wasn't it "The Marching Morons" by C. M. Kornbluth Kelly

19 years, 2 months

Short review of $550 power cord plus a new SWTPC 6800

by ajp166＠bellatlantic.net

> >Subject: Re: Short review of $550 power cord plus a new SWTPC 6800 > From: ard at p850ug1.demon.co.uk (Tony Duell) > Date: Sat, 22 Oct 2005 22:06:59 +0100 (BST) > To: cctalk at classiccmp.org > >> Very akin to those cheap import "21 jewel" watches, where most of the >> jewels are simply glued on somewhere on the movement. It isn't a lie, but >> it's a bit of a whopper. > >I read somewhere that when the originator of jewels for bearings in >watches tried to apply for a patent (or some other legal protection) for >his idea, an old (then) watch was exhibited which had a jewel in the >middle of the balance cock in appearently just the right postion, and >thus the patent was not granted. > >Only later (?) was it 'discovered' that this jewel was purely for decoration. > >And weren't there '12 transistor' radios in the 1960's where half of the >transistors had all 3 leads connected to the ground rail (and therefore >they did nothing other than enable that statement to be printed on the case). There were a few that were base 6transistor with parallel devices in the ouput amp to boost the count (8 or 10 tr). I used to buy them to harvest the extra devices or everything as they were had very cheaply. Allison

19 years, 2 months

Replacing Old LEDs

by fire＠dls.net

I believe that all these LEDs are on ISA or EISA cards, circa 1987. Let me be more specific now that I have gone to radio shack. In 5mm red LEDs they have 12volt, 2.6v, 1.8v Here are web pages: http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&product%5Fid=276-2 09 ? 5mm Red LED $1.29 ?????Brand: RadioShack Catalog #: 276-209 ?????Model: 276-209 Availability On-line: In-stock In Store: Check availability Phone: In-stock 1-800-THE-SHACK (1-800-843-7422) (Pricing and availability may vary outside the contiguous 48 United States.) Typical MCD is 1.5. Typical wavelength is 697mm. Size is T-1-3/4 or 5mm. Red lens color. Viewing angle is 36?. 10mA (max). Typical Voltage is 2.0, with a maximum voltage of 12.0V. Comes as package of 1. http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&product%5Fid=276-0 41 5mm Red LED $1.29 ?????Brand: RadioShack Catalog #: 276-041 ?????Model: 276-041 Availability On-line: In-stock In Store: Check availability Phone: In-stock 1-800-THE-SHACK (1-800-843-7422) (Pricing and availability may vary outside the contiguous 48 United States.) Typical MCD is 10. Typical wavelength is 700mm. Size is T1 3/4 or 5mm. Red lens color. Viewing angle is 30?. Current is 28mA (max). Typical Voltage is 2.25, with a maximum voltage of 2.6V. Comes as package of 2. 276-330 which is 1.8v does not seem to have web page available. Should I just put in the 12v one? And turn around if I get it wrong? or use jumpers to test it before soldering? Bradley

19 years, 2 months

Need help with a BA11-K power supply

by fireflyst＠earthlink.net

Alright, I thought I would crosspost this to see if anyone here has one of these modules. I don't even need to look at this, I remember that the relay does not kick on at all. I have a DEC jumper that runs across the two molex terminals on the back of this module that just plugs in. So, that being said, does anyone here have any of these modules? I know the other 3 modules of the power supply are common replacements, so I'm hoping someone saved a spare of these too ;) If you've got one you want to part with, let me know! Thanks Julian -----Original Message----- From: owner-info-pdp11 at village.org [mailto:owner-info-pdp11 at village.org] On Behalf Of Don North Sent: Thursday, October 20, 2005 2:20 PM To: info-pdp11 at village.org Subject: Re: Need help with a BA11-K power supply Julian Wolfe wrote: > Well, I decided to take another crack at getting my 11/34 system > working again. Currently I've still got some problems with it - > firstly though, the power supply. It blew when I hooked one of the > front panel switches up to it, though nothing seemed to be wrong as > far as what I could tell from all the diagrams. > > Right now the disassembled BA11-K box is sitting in my living room > taking up space. Now, when the PSU blew, I was able to notice that > the spark came from what LOOKED like the portion that the power cord > comes from.I looked at the traces under a magnifying glass, and > couldn't see anything wrong, and I can't smell anything. I checked all the fuses, those seem to be sound. > > In any case, when hooked up to nothing, the fans don't even kick on. On this box the fans are wired directly across the primary of the main power transformer, so unless the fans died (both of them) it would indicate that the main power relay circuit is not kicking in. The K box has a power input circuit breaker on the back that needs to be flipped to on (I'm sure you got this far) and then the power relay needs to be engaged as well. The 11/34 console switch can do this (wires run from the controller to the front panel switch) and it can also be done from the rear 3pin molex connectors as well. Short pins 1-3 to engage the power-on relay. This power circuit on module 54-13089 has it's own little power transformer and a bunch of diodes and capacitors. If shorting the pins on the molex (either one on the back will work, both are wired to the same place) does not turn the fans on, or you don't hear the clicking of the relay, then most likely the sparks that eminated from near the power cord entrance (which is this power module) were from this board, and it likely indicates blown circuitry (sparks are NEVER a good sign). Hope this helps. > Can anyone give me a test process I can go through to diagnose the > problem, or would anyone here be willing to look at the power supply > for me if I shipped it to them? > > As it is, I have this dead machine doing nothing and my girlfriend > keeps pestering me about it every time she comes over because it doesn't work. > > In any case, I'd appreciate any help that could be given to me! > > Thanks! > Julian > > ---------- > To unsubscribe (or subscribe) from (to) this list, send a message to > info-pdp11-request at village.org, with the first line of the message > body being "unsubscribe" or "subscribe", respectively (without the quotes). ---------- To unsubscribe (or subscribe) from (to) this list, send a message to info-pdp11-request at village.org, with the first line of the message body being "unsubscribe" or "subscribe", respectively (without the quotes).

19 years, 2 months

PC floppy cable twists...

by Watzman＠neo.rr.com

Re: > > ... discussion about this on another list got me curious - what *was* > the point of that cable twist in a (IBM clone) PC floppy cable, when > every other system on the planet was using straight-through cables? > There are two stories on this one. Story 1 is that the original IBM power supply was only 63 watts, and didn't have enough power to run two drive motors at once. However, the "straight-through" interface only had one motor-control line, but several (3 or 4) drive select lines. By inserting the twist, one of the extra drive select lines became an independent motor on-off control line for the 2nd drive. Story 2 is that for service reasons, IBM did not want to have to deal with drive jumpering, they wanted every drive to be the same so that drives could be simply swapped with no fuss if one failed. I worked for Zenith [Data Systems] at the time, and Zenith [different division, but we had some contact after the IBM PC was introduced] made the original power supplies for IBM [as well as the power supply for my Z-100]. We were always told that story 1 was correct. Also, the logic behind story 2 doesn't address the fact that drive terminators still had to be configured. So I say it was because of the drive motor power requirements. That's my story, and I'm sticking to it.

19 years, 2 months

Calling Mike Stein...

by gtulloch＠shaw.ca

Mike Stein, drop me a note, none of your email addresses work anymore :) Regards, Gord

19 years, 2 months

DHV (was: RL01 drive select plug and power supply questions)

by ajp166＠bellatlantic.net

> >Subject: Re: DHV (was: RL01 drive select plug and power supply questions) > From: Johnny Billquist <bqt at Update.UU.SE> > Date: Sat, 22 Oct 2005 18:47:02 +0200 (CEST) > To: cctalk at classiccmp.org > >On Fri, 21 Oct 2005, Allison <ajp166 at bellatlantic.net> wrote: > >> >Subject: Re: RL01 drive select plug and power supply questions >> > From: Paul Koning <pkoning at equallogic.com> >> > Date: Fri, 21 Oct 2005 10:58:55 -0400 >> > To: cctalk at classiccmp.org >> > >> > Allison> Yes I do. However for a single user system the load is not >> > Allison> an issue. If your running a timeshare system such as RSTS >> > Allison> or RSX with more than one user then DHV11 sense as well. >> > >> >Not true. 9600 baud is 960 interrupts per second, on a character I/O >> >device. That's a big number for a PDP-11. Output will be >> >significantly less of a burden with a DH type output controller than >> >with other types -- even for just one active terminal. >> >> Depends somewhat on the OS. It dont know about you but most people >> can't type much faster than 100WPM (less than 10 chars sec). > >Um, that's irrelevant. A DH type controller also interrupt on each >character input. It's output that differs. And filling a full screen is >1920 characters, which at 9600 bps will take about 2 seconds. Do that on >one terminal will the system will definitely notice. If you have a serial >printer of some speed (such as an LN03) we're talking about a lot more >than about 2k of data sometimes. So even with a single user system, it can >make a big impact. And of course, if you have anything else running at the >same time, it will make it even worse. Multi-user systems definitely >suffer if you use DL11 controllers for users. It's more or less a no-no. Results differ. Actualy outputting a full screen to a vt100 at 9600 causes a fair number of input chars (Xon/Xoff buffer management) and printers (la100, LN01, LN03 all have buffers larger than 2k before they assert buffer controls (be they hardware or XON/XOFF). There is a distinct differnce in system performace due to those factors. >I'm not even sure you can drive one single line at 9600 bps at full speed >on a DL11, let alone 19200. LSI-11/PDP-11/03 that is tue due to processor speed. By the 11/23B 38.4 works! (I run a TU58 that way) >> For RT11 it's mostly unimportant. For unix (the most sensitive >> to interrupt loading you _may_ care as a single user). > >It matters for both, as I've pointed out above. In theory, in the practical world there are systems where idle cycles are a reality. You have to use all of those up first. >> > Allison> For most of my 11s four lines is the limit for what I can >> > Allison> seem to keep busy. Figure a user terminal, LA100 Printer >> > Allison> and serial line for modem or data line to another system. At >> > Allison> the extreme I've run two terminals for OSs that support that >> > Allison> but, I can only type on on at any instant. ;) >> > >> >Sure, if you're mostly doing editing, then the CPU burden of high >> >speed output may not be obvious. If you had an LN03 or similar >> >printer, you might see it more easily. An LA100, of course, isn't >> >much of a problem because it is quite slow. >> >> Actually printers are a bursty load (fill the buffer and go away) >> and I've found that in practice the faster you fill the buffer >> the better (high line rates or use a parallel interface). > >Yes, and that burst will drop a PDP-11 to it's knees if it's on a DL11 at >high speed. Sure, if you're running 2400 bps then you'll live. But not >many does these days. Note the bursty loads were felt worse (incresed delays) when the baud rate was medium (below 4800). Too much "barely thinking" inbetween interrupts waiting to fill the buffer on the printer. With the LPV11 (same problems as DL only very fast parallel byte transfer ( 20-40,000bytes/S) the driver would push data from its buffer till the printer yelled wait. So the time impact was actually lower. The same driver would push a DL the same way for a LA100 or LN03 as both had big buffers and would take it fast as you could send it (9600!) and then send back XOFF to stem the tide and the system would return from the printer driver. Larger print jobs had a differnt impact but as printer speed increased their buffer sizes helped to absorb that. Keep in mid this was an office system so print jobs were typically 1-4 pages (small). Printing has a different interrupt load then interactive terminals. Interactive terminals keystrokes are slow and screen fills are the real load. Define PDP-11. The family of CPUs and performance varies greatly. For example the 11/44 could not take a TU58 at 9600, (barely at 4800). Yet I run a BA11-VA with 11/23, M8059 ram, DLV11J and MRV11 with a tu58 as boot and mass storage under RT11XM. works fine at 38.4K baud. The only slowness there is waiting for the TU58 to read the directory then seek to the file. >> Performance was good enough that we used that over the VAX >> (line lengths limited us to 2400baud in our part of the mill). > >Yes, interrupt performance on the VAX was not pretty. One or two DZ11 >on a VAX-11/750 would kill it. Yes but the limiting factor there was not the VAX interfaces but the greater than 3000ft of wire between us and the VAX. ML3-6 to ML1-1 was a long walk! Ex mill rat here! However 750 performance was pretty tepid, the DMF32 was only ok. When we moved up to it a few complained it was slower than the 11/23B but easier to use. Later on the whole mess was solved with multisessioning on LAT and LAT servers. Allison

19 years, 2 months

← Newer
1
...
21
22
23
24
25
26
27
...
66
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 October 2005