dtmf decoder

[shahtejasm]

how to get incoming no using 8051 microcontroller?
is caller id facility needed from telephone exchange??

 

[blueroomelectronics]

Caller ID is sent from the exchange.

 

[shahtejasm]

Caller ID is sent from the exchange.

hi..
that's true but i want to know that when we connect microcontroller with telephone line then is it needed that caller id facility is available for my telephone no from exchange or it is not needed??

i m able to detect dialled no from telephone one by one and display it to LCD

but i dont able to get incoming number using mt8870 whwn std pin is high.

it display only one random character.

 

[blueroomelectronics]

The MT8870 is a touch tone decoder. What does this have to do with caller ID?
http://electronics.howstuffworks.com/question409.htm

 

[john.l]

can you please post circuit diagram of interfacing of dtmf encoder with microcontroller...... please.... i need for my final year academic project...

 

[shahtejasm]

Re: DTMF Deocder

Hi john
i am sending u a circuit diagram of dtmf decoder with 8051 microcontroller.

 

[rushi53]

Hi John.L
shahtejasm has given correct circuit diagram,
for more information u can view the datasheet of the IC

can you tell us what is ur application? so that we can guide you more in this regard.