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Bio: Restored Apollo Guidance Computer, Xerox Alto. Reverse-engineering old chips. Analog computing. Added â‚ż to Unicode. Charger teardowns. Arduino IRremote library.
Location: Silicon Valley
Maybe you got there from yesterday's HN discussion? Strangely, the Klein bottles are made by Clifford Stoll, author of the famous hacker hunt book The Cuckoo's Egg.
news.ycombinator.com/item?id=245602…
news.ycombinator.com/item?id=245602…
I've never understood the framing where rising house prices are an inherently good thing and falling house prices are a bad thing. It's good for some people and bad for others.
Very cool!
In your left photo, you have the AD633 analog multiplier, which sells for $10. On the right, you have the Raytheon RC4200 analog multiplier which sells for 85 cents on eBay. Profit!
Attached is the mask pattern from the RC4200 datasheet, which exactly matches your die photo. pic.twitter.com/7XA5PElqbd
Great! It's a 7400-series IC? @babbageboole has reverse-engineered a bunch of those from die photos and has schematics. (Just in case anyone wants schematics; I don't think they will help with your problem specifically.)
project5474.org/index.php?titl…
project5474.org/index.php?titl…
Sounds like your chip is getting powered through the input protection diodes (see link). Datasheets often show this circuit. There's no easy way to get more information than the datasheet provides but I don't think a full IC schematic would help anyway.
microchip.com/forums/m514494…
microchip.com/forums/m514494…
My first thought was no, then I remembered the oatmeal box crystal radio. What about a wire-around-a-nail electromagnet? Does that count as an inductor?
A variable is any single letter, or a letter followed by one digit. That's what you're allowed in BASIC. I don't make the rules.
dartmouth.edu/basicfifty/bas… pic.twitter.com/X5jzlyoF1G
dartmouth.edu/basicfifty/bas…
Orange is the polysilicon layer, forming transistor gates or sometimes capacitors. Squiggles indicate a high-current driver transistor. The squiggle shape helps fit a larger gate into the area.
A couple of interesting things in that 1957 ad. First: "Aircraft Nuclear Propulsion". That was a real plan back then. Second, blatant sexism: "Immediate openings for men"..."Men who join General Electric"..."Also a few high-level openings for men with nuclear background"...
twitter.com/tannewt/status…
twitter.com/tannewt/status…
The Intel 8008 processor, made into a 1000-piece jigsaw puzzle. That averages 3.5 transistors per piece. twitter.com/tannewt/status…
NED: Noise Emitting Diode
Here's an article explaining why 6502 undefined opcodes work the way they do. It may be what you're looking for.
pagetable.com/?p=39
The HP Nanoprocessor (1974) was a fast control processor for HP devices, but it couldn't even add. I reverse-engineered its simple circuits from the masks including the comparator, inc/decrementer, and accumulator. righto.com/2020/09/hp-nan… pic.twitter.com/m2APtyN8si
In comparison, Canada distributed millions of free masks at drive-through Tim Hortons donut shops, which seems very Canadian.
edmontonjournal.com/news/local-new…
edmontonjournal.com/news/local-new…
Material Zoom: youtu.be/7_22lyMh0PM •–– written/produced by @saleem_ali, directed/edited by @_alextyson, with research by @lifewinning, @kenshirriff, and David S. Chun. Score by @TroyHerion, w/ footage by @videoconsortium members.
twitter.com/kenshirriff/st…
Look at the part I highlighted in red: "the virus that causes coronavirus". That's nonsense.
:-)
Seriously though, the Xilinx die numbers are a bit puzzling since they don't match the part numbers. Discussion here: siliconpr0n.org/archive/doku.p…
siliconpr0n.org/archive/doku.p…
What are they manufacturing on Venus? The first microprocessor in space was the Intel 4004, which landed on Venus in 1978 in a probe as part of a mass spectrometer. So Venus lifeforms could be manufacturing 4004 clones.
drewexmachina.com/2016/06/13/nas…
drewexmachina.com/2016/06/13/nas…
nature.com/articles/d4158…
Phosphine gas is used as a dopant in semiconductor manufacturing to create n-type silicon. Phosphine was just discovered in the clouds of Venus. The obvious conclusion is that there is life on Venus and it is manufacturing semiconductors.
nature.com/articles/s4155…
Yes, the configuration needed to be loaded into the FPGA on power on, but the FPGA handled much of the loading. You could attach a 2Kx8 EPROM or Xilinx's special serial PROM, or do terrible hacks as described here: news.ycombinator.com/item?id=244634…
news.ycombinator.com/item?id=244634…
I'd hate to be doing things that get worse and worse :-)
The Xilinx XC2064 was the first FPGA, introduced in 1985. Built from a grid of 64 tiles, each combining routing and a configurable logic block. It is programmed by memory cells across the die holding configuration data. I reverse-engineered its circuitry:
righto.com/2020/09/revers… pic.twitter.com/J45xch7SCE
The diagram is on Page 72H of the Saturn IB/V Instrument Unit System Description and Component Data.
twitter.com/kenshirriff/st…
A few people mentioned OFAC sanctions, so I investigated a bit more. In Dec 2019, US Dept of Treasury sanctioned companies linked to Serbian arms dealer Slobodan Tesic, including Cyprus-based Tardigrade Ltd. So PayPal flags tardigrade ornaments by mistake.
home.treasury.gov/news/press-rel…
home.treasury.gov/news/press-rel…
"Histories of Computing", Mahoney, has a lot about the development of new disciplines by their practitioners and their formulation of agendas. You might find it interesting although it has a focus on computing.
In the analog computer days, they used motor-controlled multi-turn potentiometers. Probably not the solution you're looking for, but I'll throw it out there.
Well, that's a pretty big drop, but if it still works then I guess nothing broke. There's a lot of foam holding stuff in place so I guess it worked. But don't blame me if anything goes wrong :-)
The die photo came out of my microscope. You're the first to see it :-) pic.twitter.com/FQT5Uhp5dD
Pretty much. The serial processor is also 5 times faster, so it is able to keep up with high-speed serial protocols better than the 8-bit processor.
The Intel 8273 is an interface chip for IBM's SDLC/HDLC network protocol. Two separate processors in one chip: a high-speed serial processor (top third) and a multitasking 8-bit processor (bottom). The same overly-complex design as the 8271 floppy controller but different code. pic.twitter.com/xmIVGAN4kV
You're asking about the white gunk on the surface? When I see something like that, I usually try vigorously to clean the die and destroy it in the process. So you might want to take advice from someone else...
In case people are confused, the #GlendowerFire is now officially called the #AlmedaDriveFire. Almeda, not Alameda. The fire started near Glendower St and Almeda Drive in Ashland; the two roads are near each other. I don't know why they changed the name. pic.twitter.com/ip4uLdvMhR
I've tried "high-level" ways of reverse-engineering microprocessors, but the only thing that works for me is tracing out all the circuitry to the transistor level. Neuroscience has too many black boxes: even in c.elegans neuron map, neurons are mysteries
ncbi.nlm.nih.gov/pmc/articles/P…
ncbi.nlm.nih.gov/pmc/articles/P…
I do it for historical interest, to reveal the unknown, to see how real circuits work, for education, it's fun like sudoku. My start: seeing the Visual 6502 simulator, cool but incomprehensible. As a programmer I felt I should understand computers better.
visual6502.org/JSSim/index.ht…
visual6502.org/JSSim/index.ht…
Probably because the images were http and thus unsecure. Try loading the page with https now: righto.com/2020/09/inside…