Yup, you're right, as always!

This guy manages to connect bucket loads of switches with just 4 lines,
however they have to be separate switches, not a matrixed array.

For those who may be interested it is app note DD4012 at:

http://www.microchip.com/Download/Appnote/Category/12CXXX/Logic/index.htm

Regards

Mike Rigby-Jones
mrjones@nortelnetworks.com


> Check the Microchip website.  As I recall, a Russian did a fantastic
> general-purpose keypad which significantly reduces I/O rqts using diodes.
>
> Andy Kunz - Statistical Research, Inc. - Westfield, New Jersey USA
>