[sdiy] Rotary encoder

[Louis van Dompselaar]

However, as 74C922 are pretty expensive ($7.50 even at Futurlec), it's 
probably
not an ideal solution...

> I seem to have been mistaken in being mistaken about turning
> 3x4 rotary switches into a marix.  At least some of them.
> I just looked at a Lorlin 3x4 and that just needs the stop
> removed to turn it into a 12-step switch.  If you then
> connect:
>  1-5-9 to Y1
>  2-6-10 to Y2
>  3-7-11 to Y3
>  4-8-12 to Y4
> and
>  A to X1
>  B to X2
>  C to X3
> it should probably work with he 74C922.