i soldered a circuit for dtmf to bcd convertor using CM8870.it works fine with landline telephone.i want to use it with a cellphone.it isnt working with cellphone.i cut the wire to speaker of handsfree of a mobile and connected to the input of ic.still its not working.i intend to use it as a remote control by calling the mobile with another mobile.plz help ,its urgent.
dear,
your cellphone should able to produnye DTMF signal caose otherwise it wont't work.
and signal from cellphone should connect to input of MT8870
regards
Like e_eja said, I think u should enable the TONE mode for the keypad in the "PHONE settings" for ur mobile, and also set it to 'LONG' tone mode.
I think it should work, we regularly use it for reaching the help desk for automated service for our service providers, they use the same thing.. -
This should do it i guess..
today i tried again.but this time i called from another cell,then i received the call,then asked the caller to press any key .it worked perfectly fine.i dont wha twas the problem.at first i used to press the key of the same cell with keypad tone activated.well anyway it worked out fine.