test-drb February 2010

test-drb@ccmp.vtda.org

175 participants
221 discussions

Y2K retrospective / was Re: Algol vs ...

by arcbe2001＠yahoo.com

I get back to my point that a lot of the comments and criticisms concerning the absence of the century in system design comes? from people ill equipped? and knowledgeable to be able to pass judgment.? By 1985 I had been working in Data Processing for 20 years!? Hardware constraints dictated what we did and didn't do.? The hardware constraints were our main obstacle and? were twofold: 1) Cost - Memory was incredibly expensive (Read The mythical man month) 2) Hardware Technology - Early systems were mag tape only.? The bottom line to this is that there is always a price point.? Added to which, and factored in, is the life expectancy of any system.? Back then it was considered around 10-15 years plus.? A lot of systems had no upward compatability and applications needed to be modified to run. In the mid 60's only large companies had systems with greater than 16K memory and disc drives.? Mag tape 800 and 1600 bpi if you were lucky was the norm.? Systems running a single job stream were common place. ?? Now the more sophisticated systems - of which the British ICT (ICL) was one - used an offset to hold dates.? The ICL 1900 range? used a technique of holding the number of days since the Jan 1st 1900.? Richard Pick later used a similar off-set technique in his Pick O/S (Dec 31, 1967).? We used assembler language because we had to.? Generally they were considered a necessary evil although I loved using it. 3rd generation language compilers weren't that mature and generated a lot of machine code instructions making them a memory hog and slow to execute. ?? While the main pack (IBM lead) pursued architecture that used Assembler, Burroughs took a different, and far better approach as their systems used Algol. In the early days when we wrote programs they were written onto coding forms.? Once punched onto 80 column cards we would check each card to ensure that had been key punched correctly.? Checking an 8000 statement? program took time.? Once checked we would have it listed (used little machine time).? We would then dry run through the program looking for logic errors.? Having done that we would have it compiled.? Typically there would be a couple of development slots or so a week for testing so we had ensure that we had done due diligence.? If it compiled we would schedule a test slot and run against test data.? Debugging consisted of analyzing dumps and correcting the code.? Contrast this against interactive source debuggers.? Today machine time is inexpensive and many compiles and test shots may be performed in a day.? "Workbench" tools allow the programmer to run their program without even hitting the mainframe.? A totally different world.? There was no padding of EDP (Electronic Data Processing) budgets - they didn't exist, there was not an EDP cost center in the G/L.? EDP was a huge investment for any company.? We didn't have an EDP Manager in the true sense of the term as we reported to the head of finance - The chief accountant.? It was later that we split off and became a separate entity with our own budget. --- On Wed, 2/10/10, Brent Hilpert <hilpert at cs.ubc.ca> wrote: From: Brent Hilpert <hilpert at cs.ubc.ca> Subject: Y2K retrospective / was Re: Algol vs ... To: General at invalid.domain, "On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Date: Wednesday, February 10, 2010, 1:25 AM William Donzelli wrote: > > > 11 years ago, I pointed this very fact out to "journalists" who were > > convinced that Y2K was all a scam to pad IT budgets because "nobody > > would have gone to that much trouble to save 4 bits (00-99 fits in 7 > > bits, 2000 fits in 11 bits) even in the 1950s. > > While it was not a scam, it certainly was used to pad IT budgets. I would argue the public aspect of the issue was a scam. The people who needed to know, knew already. The public hype around the issue was overblown and unnecessary. Remember the various experts and consultants railing about how microwave ovens and cars and anything with a microprocessor in it (things that didn't even know about the date) were going to fail? I still have the bulletin from the government mailed out to every household in Canada to prepare everyone for Y2K: a fine example of public folly.

14 years, 2 months

Barden programming books (was: Re: TRS-80 bootable media request)

by mtapley＠swri.edu

At 17:20 -0600 2/25/10, Mike L. wrote: >"More TRS-80 Assembly Language Programming", by Bill Barden A comment and a question: I found on eBay the CoCo Assembly book by the same author. It's clear, an enjoyable read, and does a good job of introducing programming, the debugger/assembler implemented on the cartridge, and 6809 assembly language in a simple, easy-to-understand progression. However, it seems to me to give really short shrift to what the 6809 designers considered to be very important features of the processor. Position independent code is barely touched on, there are a lot of what looks to me like kludgy programming techniques, the most advanced software-management tool discussed is a flowchart (and then there's no useful example of how to use them), the multiple pointer registers are abused as 16-bit counters rather than as indexing pointers, and there are many similar examples. Does anybody else have the same take on this? I was thinking about using it to teach programming to one or more of the kids, but it seems to me that I'd rather find something a bit more structure-oriented, and less likely to use "tricks". Am I just spoiled from having read the 6809 programmer's guide and the (somewhat snooty-sounding) Byte article on 6809 design and introduction? -- - Mark 210-379-4635 ----------------------------------------------------------------------- Large Asteroids headed toward planets inhabited by beings that don't have technology adequate to stop them: Think of it as Evolution in Fast-Forward.

14 years, 2 months

Windows 1.0, Windows 2.0, Windows 3.0

by legalize＠xmission.com

Does anyone have these releases of Windows prior to Windows 3.1? -- "The Direct3D Graphics Pipeline" -- DirectX 9 draft available for download <http://legalizeadulthood.wordpress.com/the-direct3d-graphics-pipeline/> Legalize Adulthood! <http://legalizeadulthood.wordpress.com>

14 years, 2 months

toner cartridge vendor

by brianlanning＠gmail.com

It looks like the toner cartridge is the source of the problems with my HP 4100. Somewhere between the $20 charged on ebay for crappy chinese cartridges and the extortionate prices charged for new ones by HP is a sane price/performance area. Can someone suggest a good vendor that charges good prices for toner cartridges that aren't junk? Thanks. brian

14 years, 2 months

VAX graphics

by bqt＠softjar.se

Richard <legalize at xmission.com> wrote: >In article <4B7AF1F7.8030008 at softjar.se>, Johnny Billquist <bqt at softjar.se> writes: >> > After searching the net for a while, I think it is an E&S graphic >> > system. ES340 seems most likely, but ES390 might also be it. > > I doubt its an E&S system because its raster based. That was a bad argument against it... :-) > AFAIK, all the E&S terminals and DEC peripherals were vector based > until the PS/390. If this were a PS/390, then it would have the > characteristic black enclosure for the monitor, keyboard and tablet. > Also, E&S products were high-end and had hardware line drawing at a > minimum, whereas this system appears to be a simple memory-mapped > frame buffer with no additional hardware acceleration. I think we should keep E&S systems apart from DEC systems. They are not the same, and mixing them up just confuses the issue. The system in the video was not something by DEC. However, DEC had bitmapped graphic systems long before this, but not with the resolution and depths shown in the video. > The PS/390 was the first "Picture System" to support raster > operations. The primary market for these peripherals was the > molecular design/molecular modeling community and they needed very > high quality line renderings of their models. Until the antialiasing > technology for raster graphics introduced on the PS/390 the only way > to achieve that quality was to use a vector based display. The raster > display decoupled the display refresh rate from the frame rendering > rate, allowing very high quality renderings of complex models at the > cost of interactivity. Well, the E&S PS/340 also was a raster display system, as an add-on to the PS/330. See http://www.bmsc.washington.edu/people/merritt/graphics/ps330/ps330.html I think it might very well be that which is shown on the video. Raster operations are another issue. The video is showing a bitmapped high resolution picture, and it obviously isn't too fast at loading another high res picture. And that is all we see them doing. No raster operations of any kind (unless you count the basic setting and clearing of pixels). > Similar technology to that used in the PS/390 was used in E&S's first > workstation the ESV. I worked on the ASIC that performed this process > in the ESV in the summer of 1989. The workstation was released in Q4 > 1989. All the E&S products were raster from then on, with the > exception of calligraphic light overlays used in the simulation > products. > > I have a PS/390 base and several ESV workstations in my collection. Nice. Johnny

14 years, 2 months

Wanted: RS/6000, 5250 Twinax cable/terminator, AlphaServer 1000A SCSI cable/terminator, DEC 3000 motherboard

by andreww591＠gmail.com

I am looking for a few things: I recently picked up an iSeries 270 and an AS/400 Model 200. A terminal and an 8-port Twinax hub were included, but not the cable to connect the terminal to the hub. The terminal has a "Y" cable with a DA15 and two female Twinax connectors. The connectors on the hub are also female, so I think that what I need is an M-M Twinax cable. I'm not sure if a terminator is required for the un-connected Twinax connector on the "Y" cable or not (I'm not really very familiar with AS/400s). I have an AlphaServer 1000A 4/266 which is missing the terminator for the internal SCSI backplane (because this is missing, the SCSI drives sometimes stop responding and cause the system to hang). It is also missing the cable to connect the two sections of the backplane. Does anybody have either of these? I have a DEC 3000/300X that no longer boots. The diagnostic LEDs show "FA", which represents a memory test failure. I think that one of the SIMM slots is damaged. When I got it, it would only boot after I removed and re-installed the SIMMs. I tried cleaning the SIMMs and slots with 99% alcohol, so I don't think that dirty contacts are a problem. I think that replacing the motherboard would fix the problem. I am also looking for an RS/6000 (preferably one with PCI rather than MCA). Does anybody have one that they want to get rid of for free or cheap?

14 years, 2 months

Visioncard

by thomas.bervenmark＠xaar.se

Dear Madam/Sir, My name is Thomas Bervenmark and I work at XaarJet AB in Stockholm, Sweden. We are looking for a very old vison card "Transtech Parallel, TMB08" with a module TTG-F card mounted on the motherboard. Is this something you could help us to find? I am not a list subscriber and so would appreciate direct email responses rather than replies to the list. Many thanks for your help in advance. Best regards, Thomas Bervenmark XaarJet AB __________________________________________ XaarJet AB Box 516 SE-175 26 Jarfalla, Sweden Phone: +46-(0)8-580 887 00 Fax: +46-(0)8-580 887 77 Website: http://www.xaar.se/ Xaar is a market-leading manufacturer of innovative digital inkjet printing technology. Note: The information contained in this e-mail is intended for the named recipient(s) only. It may also be privileged and confidential. If you are not an intended recipient, you must not copy, distribute or take any action in reliance upon it. No warranties or assurances are made in relation to safety, content and/or any attachments. No liability is accepted for any consequences arising from it. No warranties are given by Xaar, and no liability is accepted by Xaar, in relation to any loss arising from reliance placed on the information supplied in this email and attachments, other than those warranties expressly stated in Xaar's Standard Terms and Conditions of Sale. Xaar's Standard Terms and Conditions of Sale apply at all times. Xaar plc, registered in England no.3320972, XaarJet ltd, registered in England no.3375961, Xaar Technology ltd, registered in England no.2469592, Science Park, Cambridge, CB4 0XR, Tel +44(0)1223423663, Fax +44(0)1223423590

14 years, 2 months

DEC H777 PSU

by binarydinosaurs＠gmail.com

Folks, Got a PDP 11/04 on the bench here at work with an H777 (54-11599) PSU in with a sticker on it that says 'pop, bang & smoke'. I've downloaded the maintenance printset from Manx (yay Manx) but before I even begin I've noticed a terminal block on the transformer that indicates a jumper between terminals 1&2 and 3&4 for 115V and an additional jumper between 2&3 for 230V. This third jumper is missing so have the owners of this PDP just put 230V across a PSU jumpered for 115V? Thanks! -- Adrian www.binarydinosaurs.co.uk

14 years, 2 months

VAX graphics

by bqt＠softjar.se

Patrick Finnegan <pat at computer-refuge.org> wrote: On Monday 15 February 2010, Johnny Billquist wrote: >> > The two companies that springs to my mind here are Intergraph, who >> > did CAD systems based on VAXen. They usually based their systems on >> > the VAX-11/750, but I don't think there was any technical reason >> > that an 11/780 shouldn't be possible as well. > > FWIW, the VAX-11/780s I have were a part of an intergraph setup at one > point. I didn't save the drafting-table sized drawing tablets/cad > terminals that were with it, because of a lack of space... > > Alas, the setup they had didn't look like the Intergraph stuff I saw. Cool. Nice information, thanks. After searching the net for a while, I think it is an E&S graphic system. ES340 seems most likely, but ES390 might also be it. There are information about an older system for the PDP-11 machines by E&S on the net, which strikes me as very similar, and probably a kind of predecessor. Johnny

14 years, 2 months

VAX graphics

by pontus＠Update.UU.SE

Hi All. I just stumbled upon this video of a computer tablet: http://www.youtube.com/watch?v=aPC_w9yYe5M They show a VAX-11/780 with RP06 and TU70 (I think) and claim its doing the graphics. But I'm curious, what terminal and software is used? Does anyone have a clue? Regards, Pontus.

14 years, 2 months

← Newer
1
...
5
6
7
8
9
10
11
...
23
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 February 2010