October 2019 - vcf-midatlantic

Museum Report
by Chris Fala 28 Oct '19

28 Oct '19

I was docent yesterday. I have been "assistant" docent or "co-docent" before, but this was my first time completely solo. It is always fun spending time at the museum, I highly recommend it! Fairly slow day, likely due to the intense rain we had for most of the morning and early afternoon. There were two groups. Early in the afternoon, a large group of Boy Scouts came through. They seemed fairly interested, and a few of them asked some questions. One boy took pictures of pretty much everything. Later in the afternoon a young family with five small children came through. The oldest daughter seemed very interested and, like the boy scout from earlier, took pictures of everything. Chris

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someone once wanted PC-AT case, VESA/VLB bus motherboard
by Jeffrey Jonas 27 Oct '19

27 Oct '19

I remember someone once asking for a PC-AT case, and someone else asking for a VESA/VLB motherboard. I just happen to have a PC-AT tower case with a socket-3 ISA/VLB motherboard. Speak up if you still need it! -- jeff jonas

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Looking for an Apple //c Plus
by Jason Perkins 26 Oct '19

26 Oct '19

A friend is looking to buy a //c Plus. Does anyone have one they're looking to sell? Thanks! -- Jason Perkins 313 355 0085

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OT: 3D print design for ESP32 VGA dongle
by Bill Degnan 25 Oct '19

25 Oct '19

Hi - Any one have a 3d printer file URL or if it does not exibt be interested in a little ($paid) project to make an enclosure for this device: *https://tinyurl.com/yy8uhffv <https://tinyurl.com/yy8uhffv>* "LILYGO® TTGO VGA32 V1.2 Controller PS/2 Mouse And Keyboard Graphics Library Game Engine And ANSI/VT Terminal For The ESP32" I have the printer but I don't have a scanner.. This is for a product to be sold at the Kennett Classic shop. Contact me privately through vintagecomputer.net/contact.cfm Thanks Bill

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Big Beautiful Vintage Computers, and Where To Find Them
by Paul Birkel 25 Oct '19

25 Oct '19

Congratulations Dave. Hittin' the "Big Time" :->. https://hackaday.com/2019/10/23/big-beautiful-vintage-computers-and-where-to -find-them/ -----

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Re: [vcf-midatlantic] computer superstitions
by Jeffrey Jonas 25 Oct '19

25 Oct '19

> You need three sync's for it to work... > sync > sync > sync > halt I'm unsure there was a halt or shutdown for Unix v6. I think one just halted the CPU. There's a good reason for three syncs. The "sync" command only schedules/initiates the buffer/cache flush. The disk writes took time, so typing it 3x on a teletype was a simple way to delay the operator enough for the writes to complete before halting the system.

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computer superstitions
by Jeffrey Jonas 23 Oct '19

23 Oct '19

"Scandinavia and the World" is an online comic with an International flavor. This time literally: https://satwcomic.com/hangry-computer looking that up leads to: https://en.wikipedia.org/wiki/The_Kuai_Kuai_culture Kuai Kuai culture is a phenomenon in Taiwan wherein workers put snacks of the "Kuai Kuai" brand next to or on top of machines. Workers who do this believe that, because the name of the snack - "Kuai Kuai" - stands for "obedient" or "well-behaved," it will make a device so adorned function without errors. As such, it can be commonly found in myriad places of work in Taiwanese society. A rigid set of best practices has arisen surrounding the proper use of Kuai Kuai snacks, such as using green bags only, and ensuring the snacks are not expired. other programming/computer superstitions: https://www.red-gate.com/simple-talk/opinion/opinion-pieces/programmer-supe… and kinda related to that: http://catb.org/jargon/html/magic-story.html -- jeff jonas

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MORE ado about chording keyboards
by Jeffrey Jonas 21 Oct '19

21 Oct '19

William Arthur Stewart Buxton ... is known for being one of the pioneers in the human–computer interaction field. https://www.microsoft.com/buxtoncollection/type.aspx?t=Chord%20Keyboard chording keyboards from Bill Buxton's collection of unusual computer interface devices https://en.wikipedia.org/wiki/Bill_Buxton the photo shows Bill Buxton with a Microwriter chord input device his own web site: https://www.billbuxton.com/

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Museum Report 2019-10-19
by Jeffrey Brace 20 Oct '19

20 Oct '19

Good day at the museum. Maybe 20 people stopped by. About 1/4 of them were high interest, 1/2 medium interest and 1/4 low interest. It's always fun to see visitors who see things differently or ask questions that you have never gotten before. I love the new LED screens on the "top shelf" machines. I look forward to seeing demos for them soon. :) Steve Anderson stopped by and dropped off his Dig-Comp 1. We chatted for a while about what's new with VCF and he had some personal perspective on many of the artifacts and explained to me how some of them were used and operated. I appreciate that since I'm weaker on my knowledge of 50's and 60's machines. I also worked on my demo of Geck OS, which is Unix for the C64. Interesting piece of software. Quite impressive that it works on a C64. Mouse will be docent tomorrow. -- ========================================= Jeff Brace Vice President Vintage Computer Federation

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Sep 28 2019 workshop followup
by Jeffrey Jonas 19 Oct '19

19 Oct '19

I had a wonderful time at the Sep 28 2019 workshop. I could not attend Sunday in order to start the Jewish New Year properly with family and friends. I already followed up Eric Rangell's chording keyboard prototype with "much ado about chording keyboards". I was beyond impressed with Nevell Greenough's LPG-30 emulator. The front panel looks absolutely authentic, albeit with an LCD instead of the 3-trace oscilloscope. I frobbed an LGP-21 back in high school and I remember a lot about it. We geeked out about the strange opcodes that ENCOURAGED self modifying code, mostly out of necessity due to the lack of registers or stack. For example, there are 2 instructions for modifying the address field on an instuction. One saved the program counter plus 1 in the address field of an instruction. That's how it did subroutines: store the return address in the jump/branch instruction at the END of the subroutine, then jump to the subroutine start. Another saved the accumulator to the address field of an instruction. That was probably for address calculations in lieu of index registers. It's essentially a "move under mask" since the address field was NOT the entire word. http://ed-thelen.org/comp-hist/lgp-30.html <<< main page http://ed-thelen.org/comp-hist/lgp-30-man.html <<< programming manual But those intentionally PREVENTED any address overflow into the opcode. So how did Mel use an overflow to cause a branch? We think it's possible he incremented the address of a branch instruction by loading the entire instruction into the accumulator, adding to that and storing the accumulator back into (drum) storage. That's the only way to overflow the address over the 2 unused bits between the opcode and address to increment the jump into the instruction, which is a different jump/branch. And that's why Mel is *still* a "real programmer" :-) -- jeff jonas

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