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ENIAC Video ... and some 1130s
by Bob Flanders 06 May '16

06 May '16

On YouTube, there are some interesting videos in the "Computer History Archives". This one is about ENIAC. https://www.youtube.com/watch?v=bGk9W65vXNA If you look carefully, there are four IBM 1130s in this film starting at about the 7:33 mark https://www.youtube.com/watch?v=Tb0cRL2mnbA Bob

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Re: [vcf-midatlantic] Steve Dompier's coding...
by Dan Roganti 06 May '16

06 May '16

On Thu, May 5, 2016 at 8:56 PM, Bill Sudbrink via vcf-midatlantic < vcf-midatlantic(a)lists.vintagecomputerfederation.org> wrote: > How about a quiz? > > See if you can answer before Herb (who can probably answer > without even looking...) > > 1) What 8080 instruction did Mr. Dompier use as a debugging > "breakpoint"? > > 2) How could he tell that the code reached his "breakpoint"? > > 3) What secret (or at least undocumented) keystroke did he > implement to facilitate punching his work to paper tape? > > 4) What drawback did his method have? > > > dude, I did too much lsd and pot in those days to worry about trivia if you want to talk about how to debug code then that's another story But lately , I'm knee deep in 6502 code every night I would be very glad to read about this as a history article on your website Dan

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Re: [vcf-midatlantic] Steve Dompier's coding...
by Dan Roganti 06 May '16

06 May '16

On Thu, May 5, 2016 at 4:50 PM, Bill Sudbrink via vcf-midatlantic < vcf-midatlantic(a)lists.vintagecomputerfederation.org> wrote: > Herb Johnson wrote: > > > [Cromemco Dazzler Dazzlemation...] > > > .... Mr. Dompier hand wrote that program > > > LITERALLY (hand, pencil, paper), no editor, no assembler. > > > He then toggled it in (or maybe raw keyed it in with a > > > primitive ROM monitor) and [used paper tape to save/restore it] > > > > I agree, it's informative to look at such code, to see methods of > > coding. But that's normal activity, given the era. > > And I agree with you. I did some myself. I was trying to interest > some of the people who might not be aware. I've exhibited my IMSAIs > and Altairs a number of times. On numerous occasions, I've heard > comments like "those front panels are pretty but you couldn't really > do anything with them". I'm pretty sure now that Mr. Dompier > toggled Dazzlemation into the machine. The recollection is that he > didn't get a 4FDC until later, so he probably didn't have a monitor > in ROM. > > Bill S. > > > yes, I still kept most of my programming code and notes here in my Altair and Imsai manuals using the obligatory yellow legal pads from the 70s. It was not just common practice, but *required* Dan

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Re: [vcf-midatlantic] Steve Dompier's coding...
by Dave McGuire 05 May '16

05 May '16

On 05/05/2016 04:50 PM, Bill Sudbrink via vcf-midatlantic wrote: >>> .... Mr. Dompier hand wrote that program >>> LITERALLY (hand, pencil, paper), no editor, no assembler. >>> He then toggled it in (or maybe raw keyed it in with a >>> primitive ROM monitor) and [used paper tape to save/restore it] >> >> I agree, it's informative to look at such code, to see methods of >> coding. But that's normal activity, given the era. > > And I agree with you. I did some myself. I was trying to interest > some of the people who might not be aware. I've exhibited my IMSAIs > and Altairs a number of times. On numerous occasions, I've heard > comments like "those front panels are pretty but you couldn't really > do anything with them". I'm pretty sure now that Mr. Dompier > toggled Dazzlemation into the machine. The recollection is that he > didn't get a 4FDC until later, so he probably didn't have a monitor > in ROM. Many years ago, in the mid-1970s, there was a construction article in, I think, Popular Electronics magazine, for basically a blinking light panel. It had a field of LEDs that blinked randomly, nothing more. The article stated that the blinking lights on large computers of the day were simply there to impress their owners, and that "a painted metal panel would convey the same amount of useful information". Since such machines were prohibitively expensive for the hobbyist, there should be a way for the average hobbyist to "get a decent set of blinking lights", hence that construction project. The article's author was clearly completely (and dismissively!) clueless about what computer front panels are really all about. -Dave -- Dave McGuire, AK4HZ New Kensington, PA

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black Apple arrived
by Evan Koblentz 05 May '16

05 May '16

Needs a cleaning, but otherwise it looks good. Have not done any functional testing: http://vcfed.org/evan/darth.jpg Also came with this stand/port consolidator thingamajig: http://vcfed.org/evan/ports.jpg We have one floppy drive as well.

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Lo-Tech Z-80 Test Board
by Al Hartman 05 May '16

05 May '16

Thought people on the list might find this useful... https://www.lo-tech.co.uk/wiki/Lo-tech_Z80_CPU_Test_Adapter -[ Al ]-

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Steve Dompier's coding...
by Bill Sudbrink 04 May '16

04 May '16

I took a peek at the access logs for the Cromemco Dazzler files that I recently put up on my web server. I'm gratified to see that a lot of people are taking advantage of the availability of these documents, that have not recently (if ever) been easily available on the web. I also see that a lot of people took the Dazzlemation HEX file and the Magenta Martini paper tape image, presumably to run on Udo Monk's great Windows Cromemco Z1 simulator. Also, thanks to everyone that generated pdf files for me! One thing I noticed is that not many people looked at the disassembly of Dazzlemation. If you are an 8080 or Z80 programmer (or any 8-bitter for that matter) I really recommend that you take a look, it's a real treat. I'm reliably informed that Mr. Dompier hand wrote that program LITERALLY (hand, pencil, paper), no editor, no assembler. He then toggled it in (or maybe raw keyed it in with a primitive ROM monitor) and went through a few iterations of: 1) store to paper tape 2) modify in memory 3) test 4) go to 1 It's neat to see some of the "tricks" he used and also the level of sophistication of the code. It does a lot of stuff in not a lot of bytes. Also, here and there, in "dead" areas, you can also see the debris of ideas that he started and then abandoned. Bill S.

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Anyone live in/near Center City Philadelphia?
by Evan Koblentz 04 May '16

04 May '16

If so, then email me privately.

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XT-IDE rev 3 Preorder
by Systems Glitch 04 May '16

04 May '16

All, As discussed on the forums ( http://www.vcfed.org/forum/showthread.php?52343-Anyone-Selling-XT-IDE-Cards ) I'm doing a revision 3 of the XT-IDE board. The design is simplified and the routing is completely redone, and much cleaner! To gauge interest and try and guess at what size of initial order I need to do, I've put together a preorder form: http://www.glitchwrks.com/xt-ide/preorder This allows you to specify how many bare boards, kits, and/or assembled+tested units you're interested in. You'll get a confirmation email with a link to validate your preorder. If you don't validate within 48 hours, the preorder will be dropped. Thanks, Jonathan

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VT320 CRT replacement?
by David Riley 03 May '16

03 May '16

I have a VT320 with a pretty bad case of Being Old. The screen is so dim that even with all the lights off in the basement, it's difficult to read (and if it gets switched to 132-character mode, next to impossible). I know surplus caches of these CRTs pop up every once in a while, and I know other mono CRTs of the same size are often mechanically and electrically compatible, but I'm a bit at sea. Does anyone have pointers for acquiring such things? The current tube is amber, but I really don't care what color it is as long as it's legible. Failing that, how well do rejuvenators really work on these? My understanding is that it's usually a pretty temporary fix at best (like Retr0Brite). - Dave

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