[sdiy] rotary encoder?

[Ingo Debus]

Am 08.01.2009 um 19:52 schrieb Cary Roberts:

> I emailed Mark this suggestion privately last night.  But the only
> reason to do this over a microcontroller is if you wish to avoid  
> using a
> microcontroller.  A small PIC is a quarter of the cost (and less than
> half the board real estate) of a design using 74LS148s.

Hm, sure about the cost? We'd need a device with 16 I/Os here, 12 in  
and 4 out.

Here's another weird idea: you could make a switchable voltage  
divider (string of 11 resistors) and feed that into a 4 bit ADC. A 4  
bit ADC can be made of 4 opamps and a lot of resistors, something I  
learned here on this list many years ago. Of course you could use a  
microcontroller with on-chip ADC instead, this time with really low  
pin count.

Ingo