The progress so far

A project log for Discrete YASEP

a 16-bits YASEP computer (mostly) made of DIP/SOIC chips like in the 70s and 80s... with 2010's twists!

yann-guidon-ygdesYann Guidon / YGDES 10/22/2015 at 01:150 Comments

Dear blog/wiki/reader,

October 22nd (2015), the project is on track :-)

In 2016 I expect to prototype the 3 "pages" that I have already presented (1A, 1B and 2). The 3 memory pages should follow, they are very similar, though the up/down increment will be another challenge. I'll test the schematics and parts on prototype boards before doing the kapton layout and fabrication.

The clock and the 7 segments display questions are solved. However other questions remain unanswered... I'm not sure yet how I will implement the keypad.

Another burning question : how do I implement some of the arbitrary logic with cheap and surface-mount devices ?

The original idea was to use DIP devices, diodes and other discrete stuff, I would use E(E)PROMs for logic blocks... Now, even something as simple as the lookup table of the 7 segments LED display is a headache !

Aren't there SOIC PALs ? (22V10 are in DIP AFAIK) Lattice has some interesting products (TQFP, low price, 3.3V compatible, ...) but isn't it overkill for the LED decoding application ?

ATF16V8 and ATF22V10 are available in PLCC20 and PLCC28 but I don't have any software or programming adapter (what's the protocol by the way ?)

What other solutions are out there ?