Shahzad Aslam wrote:
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but i can not dial any other number on the exchange.
pls don't tell me that my circuit is not generating other tones.

your circuit may be generating other tones but your local telephone exchange could not decode it.
The reasons may be timing or level or both. make sure that the tone period is 40ms and gap between digit is 40ms or more. If your MT8888CS is configured for burst mode you need not worry about this timing problem.

Build a dtmf decoder and feed your signal and decode it, still if you are getting only '1' and nothing else then check your software. make sure you are initialising MT8888 properly, configure it in burst mode and dual tone generation mode.


regards
Murugan AKT