Software DTMF

Good evening!

Is there a software implementation of encoder/decoder DTMF for Arduino?


DTMF = Dual Tone Multiple frequency

To decode you need an integer FFT to determine the frequencies To encode a signal in software is more difficult as the Arduino has no analog out, so you need extra hardware and if you buy extra HW why not a DTMF chip directly ...

What is your project/goal with the DTMF? can you tell us more? maybe there are other solutions.

ASAIK, no. But there is atmel's application note AVR314 (DTMF generator: To decode, you can use FFT code: Other option, re-write code AN219 (Goertzel algorithm) from Silabs:

Try tone library, it works