test-drb July 2004

test-drb@ccmp.vtda.org

259 participants
518 discussions

by jbmcb＠hotmail.com

I'm not sure what the exact criteria are, but I'm almost positive the SAGE system would have a real time clock. Tracking inbound bogeys is pretty time-dependant :) http://www.eskimo.com/~wow-ray/sage28.html _________________________________________________________________ Discover the best of the best at MSN Luxury Living. http://lexus.msn.com/

20 years, 4 months

HP analyzer probes

by philpem＠dsl.pipex.com

Hi all, My HP 1651B logic analyzer arrived this morning, sans probes. The seller says he "thought they were in the pouch on top, where the bootdisk is" and that he "didn't have any left in stock anyway". Rather typically, all that was in there was a single 40-pin woven cable (HP part number 01650-61607) and the bootdisk. Murphy's Law at work. So... Does anyone have spares of any of the following Hewlett-Packard or Agilent parts in their collection that they'd be willing to part with? 01650-61607 Woven cable, IDC40 to IDC40 (I need 1x of these) 01650-61608 Probe, IDC40 to flying-lead (I need 2x of these) NOTE: the probe module should also include grabber probes. There doesn't seem to be anything even remotely close to this on Ebay at the moment, well, at least there's nothing that's available to the UK. Plenty of probe kits available USA-only though... Thanks. -- Phil. | Acorn Risc PC600 Mk3, SA202, 64MB, 6GB, philpem(a)dsl.pipex.com | ViewFinder, 10BaseT Ethernet, 2-slice, http://www.philpem.dsl.pipex.com/ | 48xCD, ARCINv6c IDE, SCSI ... Memory is a thing we forget with.

20 years, 4 months

Old EPROM questions again, EPROM Programmer

by Lee.Davison＠merlincommunications.com

>>I have a couple of "ultraviolet" LEDs with me, but I doubt they are the >>right frequency to erase EPROMs. > If they're the high power UV LEDs then they should work. A friend of > mine uses those to erase his EPROMs and the erase time is about the same > as for a UV light. There are not yet available UV LEDs that radiate at short enough wavelength to erase EPROMs in a reasonable time. Most EPROMs will start to erase at <400nm but take hours of exposure, to erase an EPROM in 20 mins or so needs 12mW/cm^2 of 257nm light on the die face. The longer wavelengths just warm the chip up a bit. This is why UV tubes for photo resist and similar won't erase EPROMs either, they output nearer 400nm which is where state of the art UV LEDs are at. Lee. ________________________________________________________________________ This e-mail has been scanned for all viruses by Star Internet. The service is powered by MessageLabs. For more information on a proactive anti-virus service working around the clock, around the globe, visit: http://www.star.net.uk ________________________________________________________________________

20 years, 4 months

REAL TIME CLOCK

by LAAG＠PACBELL.NET

THE COMPUTER AUTOMATION COMPUTERS HAD A HARDWARE INTERRUPT FOR A REAL TIME CLOCK AND THEN THE SOFTWARE WOULD UPDATE THE INFO AT THE SELECTED INTERVAL... THESE CAME OUT IN 1970 OR SO...

20 years, 4 months

More HP microcode & loader rom detective work

by dwight.elvey＠amd.com

>From: "Jay West" <jwest(a)classiccmp.org> > >I had written.... >> Microcode roms I can't identify: >> 1816-0996 >> 1816-0997 >> 1816-0998 >> 1816-0999 >> 1816-1000 >> 1816-1001 > >OMG OMG!!! Are these the E series 2000/Access IOP firmware????? >YESSSSSSSSSS!!!!!!!!!!!!!!!!????? > >--- >[This E-mail scanned for viruses by Declude Virus] > > Hi Jay OK, take a deep breath. Explain what IOP firmware is? Dwight

20 years, 4 months

IBM PS/2 systems going...

by vcf＠siconic.com

Going... Anyone interested? Their pardon runs out tomorrow... PS/2 Model 50 PS/2 Model 50Z PS/2 Model 35 SX -- Sellam Ismail Vintage Computer Festival ------------------------------------------------------------------------------ International Man of Intrigue and Danger http://www.vintage.org [ Old computing resources for business || Buy/Sell/Trade Vintage Computers ] [ and academia at www.VintageTech.com || at http://marketplace.vintage.org ]

20 years, 4 months

8" floppy project

by Lee.Davison＠merlincommunications.com

> So what happens if you try to do disk access while displaying > animations? The animations get displayed, the disk gets accessed. There's enough performance available to handle four disks and the display simultaneously. Lee. ________________________________________________________________________ This e-mail has been scanned for all viruses by Star Internet. The service is powered by MessageLabs. For more information on a proactive anti-virus service working around the clock, around the globe, visit: http://www.star.net.uk ________________________________________________________________________

20 years, 4 months

First computer with real-time clock?

by dave04a＠dunfield.com

>> This is basically a "digital clock" chip with BCD outputs (intended to >> drive BCD to 7-segment decoders) on an S-100 board. The fact that it >> is a chip intended for a clock display gives rise to certain odd >> characteristics: > >The chip used in the HP 98035 (RTC module for the 9825) is even worse. >It's got 7 segment outputs... Egad! - that is definately "worse". >> - To set the time, the software has to "hold down" Fast and Slow time >> set buttons, and watch the time value scroll by until the desired >> setting is reached - just the way a human would set a digital clock >> from that era. > >YEs, that's done in the 98035 too. In fact it's just like a digital watch >with one button to select hours/minutes, and a second press for secondes, >and one button for setting (or something like that). Quite fun to watch >the signals when it's 'writing' the time to the battery-backed clock chip. This was the older fast/slow set style - the kind that used to drive me craze in clocks - you hold down "fast" and the digits count like crazy (minites and hours), you switch to "slow" when you get close. It was really annoying if you overshot, because you had to "go round" again. When I first started writing the software to set the clock, I assumed that the computer would be plenty fast to simply watch the time in "fast" mode and stop "right on the button" - I quickly found out that the display refresh in the clock chip didn't keep up with the "fast" counter, and sometimes (rather often) it would "miss" a digit, going for example directly from '1' to '3' --- So I had to implement detection when it got "close" and switching to "slow". Regards, -- dave04a (at) Dave Dunfield dunfield (dot) Firmware development services & tools: www.dunfield.com com Vintage computing equipment collector. http://www.parse.com/~ddunfield/museum/index.html

20 years, 4 months

a classiccmp electronics project?

by dwight.elvey＠amd.com

>From: "Jay West" <jwest(a)classiccmp.org> > >Tony wrote... >> I would doubt it. Those old fusible-link PROMs were actually quite fast >> with access times of <50ns in many cases. And the designs depended on it. >Surely that's easy to get around. Upon power up - or when a reset button is >pushed, the device reads the image from EEprom and places it into SRAM, >which is what is actually accessed. Isn't SRAM fast enough? > >Jay West > > Hi Jay Yes, those CMOS RAM's used for cache that were in the narrow packages were quite fast enough. As I stated in a previous post. Dwight

20 years, 4 months

a classiccmp electronics project?

by dwight.elvey＠amd.com

Hi Jay Al and another fellow at Monday pizza talked about this. One could setup using one of the high speed CMOS cache chips, pic ( or processor of your liking ) and an EPROM. One can hold the reset signal until you'd transfered the image to the CMOS ( it would have space for just about every combination ). One could even use a flash instead of an EPROM and then add a serial port to download. Most of the fused ROM's used in the original were in the 50 to 60 ns range. Most 8Kx8 cache RAM's are in the 20 to 30 ns range. It sure sounds like a project that can be done. Dwight >From: "Jay West" <jwest(a)classiccmp.org> > >Ok, I don't know if this is possible, but it would be handy so I'll throw >the idea out and see if the more electrically inclined have any ideas. > >My specific issue is the HP2100A, 2100S, and 21MX M/E/F systems. However, I >suspect this problem is present in other machines... DEC, DG, etc. > >The loader roms and microcode roms (two different chips) for each system are >pretty much impossible to find. I'd like to make copies of them both for >myself to use in other systems I currently have, and also to have a set of >spares around. In addition, I'd like to make copies for other classiccmp'ers >who may have systems that want/need a particular firmware or loader rom >option. Finally, there are some roms that people have posted images for >online that I'd like to burn myself because I don't have those particular >roms. > >Since the blank chips are nigh impossible to find anymore... is it possible >to use something like a PIC chip on a small DIP carrier card, that could be >plugged into an existing loader rom or microcode rom socket and function >just like the "real thing" to the system? Would this be something terribly >difficult to build? A cute twist on this.... extending the idea further.... >Put a bunch of NVram or an EEprom on the little carrier card. In the NVram >could be stored multiple ROM images. Then via a switch on the card (when the >system is powered off of course), you could select if the chip was a mag >tape loader rom, or a paper tape loader rom, etc. For the microcode roms you >could switch between FFP and IOP for example. When you wanted to change the >set of rom images in the DIP package, you just hook it up to a serial port >and download to change the available sets on it. > >The WCS card for HP boxes comes close to this, but there's no battery >backup, and you can't program it easily with a PC. WCS cards probably aren't >terribly easy to find anyways. > >Is this a pipedream? It would allow DEC'ies to have more loader roms they >dont currently have by exchanging images via the net, etc. Not just an HP >thing - but I realize it would have to be a different design electrically to >work on the other machines. I'm thinking of a universal rom with different >electrical interfaces on the carriers perhaps? > >Everyone talks about preserving ROM/PROM contents. But if the blank roms are >unobtainium, we need to take the next step. > >Any thoughts? > >Jay West > >--- >[This E-mail scanned for viruses by Declude Virus] > >

20 years, 4 months

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test-drb July 2004