Detecting DTMF with voice modems

syking used Ask the Experts™
Can voice modems detect DTMF tones? I'm trying to write a software that simulates a call center, like you know "press 1 2 for...." Can I use the AT commands for this? If the DTMF functions are not part of Hayes Standard AT commands, does this means every manufacturers might have different commands with regards to DTMF?
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you can send AT commands to generate DTMF's, they call can do that. but modems don't ever send at's back to you, they only reply.

some can detect received dmtfs, some can't.
if it can't, that's ok, since the modem would probably store the audio in memory somewhere. You can read that memory, apply some DSP techniques (fast fourrier transform) to check what the frequencies in the signal are (and the duration), and if they meet the requirements, you've got a tone :)

I'd suggest you check the chip on your voicemodem and see whether there are any development tools for it.


I see. Hmmmm, I think I need a different approach

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