
Build Your Own FPGA (2012) - hinzundcode
http://blog.notdot.net/2012/10/Build-your-own-FPGA
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tyingq
Don't miss the gem in the comments...someone answers this question there:

 _" Hi. Is possible use this like a "industrial" fpga? For example, for
minning bitcoin? Because the fpga is very expensive here in Brazil, and the
7400 is cheap. "_

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progre
Top comment on the post (from 2012) is by Lee_Felsenstein [1] of Homebrew
Computer Club fame and designer of the Osborne 1, the first successfull
portable computer (Lee had no part on tanking the company though, Osborne did
that all by himself). Quite awesome to have such legents comment on your
project.

[1]
[https://en.wikipedia.org/wiki/Lee_Felsenstein](https://en.wikipedia.org/wiki/Lee_Felsenstein)

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osamagirl69
I love the idea of this! It reminds me of the megaprocessor project[1] but
much more accessible in its scale, and way easier to understand.

The writeup is very clear, and the boards themselves are very easy to follow
in operation. The more I think about it, the more I feel the need for a wall
sized array of them acting as a clock. Maybe with a flipdot display for the
time? The main issue I see is that the busses are pretty narrow and the there
isn't a dedicated crossbar for the routing so the placement is going to be
really challenging and probably involve a lot of 'inactive' modules that are
just acting as a passthrough for the wiring.

[1][http://megaprocessor.com/](http://megaprocessor.com/)

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remexre
Hm, this makes me wonder, are there any hand-assembled TTL computers that can
send UDP packets on the internet? ChaCha20 is easy enough to implement and
simple enough that you could probably do encrypted chat between two almost-
definitely-not-backdoored computers if so.

EDIT: though, I supposed you don't need your NIC to be trusted any more than
your ISP's router, so an esp8266 might be sufficient.

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Teknoman117
[http://www.homebrewcpu.com/](http://www.homebrewcpu.com/)

A computer built from 74-series logic running Minix (with a full tcp/ip
stack). Once upon a time you could telnet into it.

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amelius
Perhaps someone can design an FPGA and have it fabbed by Google for free! See:
[1]

[1]
[https://news.ycombinator.com/item?id=23755693](https://news.ycombinator.com/item?id=23755693)

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pabs3
Another open FPGA project:

[https://github.com/haojunliu/OpenFPGA](https://github.com/haojunliu/OpenFPGA)
[https://www.eecs.berkeley.edu/Pubs/TechRpts/2014/EECS-2014-4...](https://www.eecs.berkeley.edu/Pubs/TechRpts/2014/EECS-2014-43.html)

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tripletao
I like this. Real FPGAs use the same realization of an n-input LUT as a 2^n
bit shift register plus a mux, which is why e.g. Xilinx lets you have an SRL16
for the same cost as a LUT4--the shift register is primarily intended to hold
the LUT configuration bitstream, but you can repurpose it as user logic.

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dfox
The form factor kinda reminds me of mostly misguided project I toyed with in
early 00's. The idea was to get useful amount of computing power for massively
parallel applications on shoestring budget by building 2D network of boards in
this form factor that either contained “8051 on steroids” MCU or small-ish
Altera CPLD.

~~~
pkaye
Tilera was doing this but it never caught on. Probably just hard to build
applications that fully utilize its capabilities.

And Green Arrays did the same on the lower end but with forth language
processors.

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dang
If curious see also

2017
[https://news.ycombinator.com/item?id=14643474](https://news.ycombinator.com/item?id=14643474)

Discussed at the time:
[https://news.ycombinator.com/item?id=4726724](https://news.ycombinator.com/item?id=4726724)

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kazinator
The circuit board modules that make up the cells of the FPGA are reminiscent
of PLC's.

[https://en.wikipedia.org/wiki/Programmable_logic_controller](https://en.wikipedia.org/wiki/Programmable_logic_controller)

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rectang
This is a blog post from 2012, which should be noted in the title of the HN
discussion by appending "[2012]".

~~~
dang
Added. Thanks!

