| The project is designed to display the number dialed on telephone on seven segment display for better visibility. The project uses DTMF concept where every button of the telephone produces a unique frequency on being pressed which is received and decoded by a DTMF decoder. These decoded signals are then provided to microcontroller (of 8051 family) using buffer circuits for processing. The output thus generated by the microcontroller is delivered to parallel connected seven segment display. The seven segment display operates in high multiplexing mode that displays the numbers instantaneously as soon as dialed. The DTMF receiver is connected to the ear phone socket for receiving data. |
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