[sdiy] Logic for rotary encoders

[Leif]

Hi

I have a microcontroller that is going to do some midi and control a dsp...

I've been looking into putting some controllers, rotary encoders... 40 of 
them to be exact... + some switches as well.

I know that I can do groups of 16 and 16 encoders, and then use 74hc165 * 4 
(8 bit parallel to serial shift registers) per group of 16 to do a 
conversion of the data from 16 parallel inputs to a serial data 
stream...  but for 40 controllers we would get 12 chips... which is a lot.

I only have a 8 bit port to use for the controllers, so I find the shift 
register thing ok, but not very good... Anyone know a better way to do it ?

I might of course use a small microcontroller just to take care of the 
counting and data, then send it to the first, but that is a expensive design..

cheers,
Leif