1992: Intel ETANN

Intel developed an EPROM based analog NN chip called the ETANN, Electronically Trainable Analog Neural Network.  Mark Holler was the Program Manager in Santa Clara.  They wanted customers to be able to experiment with it by wiring many together for a large network interfaced to external data sources and sinks.  I produced this board solution.  ETANN was a 256 pin device and needed 8×256 pin zero-insertion force 3M sockets for the whole system.  To allow arbitrary wiring every pin needed to be accessible.  So I brought out every pin to a press fit wire wrap header.  Most boards were shipped with a bag of 8 position jumper blocks so that people could use shunt bussed connections where appropriate.  The corner socket was for the interface to their PC-based software development system which you can see deployed in the smaller insert photo.  So there were about 4500 press fit socket pins on board, areas for prototyping along with opto-couplers for interfacing to the analog.

ETANN Multichip Board with host system

I had a mechanical design mentor who was a top machinist with a shop, Frank Mertsoc.  He built me a test fixture that I used to crank the sockets into place very carefully several at a time on a milling machine using it as a deep-throated press that he also loaned use of.   Without that, I’d still be working on this project.  Thank you Frank, RIP.

Intel ETANN Multichip Board (EMB)