Hi all,

I neeed to detect DTMF tones with a 16C61, I saw a design using this PIC.
The tone was applied to A/D conversor.
There was digital filters at 1380, 1500, 1620, 1740, 1860 e 1980 Hz.
I need to identify the combination of any two of this frequencies, all did in
software, any idea?

Octavio