[vcf-midatlantic] much ado about chording keyboards

[Eric Rangell]

Hi Jonathan,
Let me know if this diagram has what you are looking for:

https://github.com/erangell/VCFEast2019/blob/master/KeyboardDecoder.png

When a key is pressed, it will connect a Pad to a Rail, so the Q key
connects pin 12 to pin 21.  The decoder can then send current through each
pin and see if any of the other pins are receiving the voltage.  Control
and Shift can be read independently of other keys using pins 2, 3, and 23.
My encoder board is from The Keyboard Company, model # KB20-0016-00.  The
encoder chip is labelled: 331-0931-B  KR3600-070  SMC  8151 with another
marking of 8-82.

Eric