Decoding DTMF


#1

Hello,

I need to decode DTMF signals to control my robot but how can I do this with GSM module?
Do you know which GSM module support this feature? and how?

Thanks alot


#2

Why do you need to use DTMF?

It’s not a terribly effective way to use a GSM link…


#3

I want to use cellphone numbers 1-9 to control my robot. That is the reason.


#4

Isn’t that going to work out rather expensive…?


#5

yes but I need this to control my system whereever I want. Not like RF, wi-fi or bluetooth.


#6

“RF” just stands for “Radio Frequency” - GSM is, of course, an RF connection…

(as are WiFi and Bluetooth)…


#7

For RF I mean RF com. modules. Thanks for RF explication. Can you help me for DTMF or not?
I dont want to discuss details. thanks.


#8

Note that, when you press the buttons on a cell phone, the phone itself doesn’t actually generate DTMF; instead, it sends signalling messages to the GSM network, and the GSM network generates the tones as they leave its digital network.

The GSM speech codecs are optimised for speech, and don’t carry DTMF too well - but Wavecom do claim to be able to do this with the DSP features in some modules.

Download the latest SDK, and look in the ADL User Guide under “Audio Services”…


#9

Thanks. Yes I heard that the wavecom modules have this feature.

I couldnt find the SDK, where can I download?


#10

viewtopic.php?f=3&t=3155&p=11729&hilit=SDKs#p11729