13.8. Calling Line Identification (Caller ID)Function:The caller ID is a chargeable ID which the user ofa telephone circuit obtains by entering a contract with the telephone companyto utilize a caller ID service. For this reason, the operation ofthis circuit assumes that a caller ID service contract has beenentered for the circuit being used.The Caller-ID data from exchange is supplied to the telephone using either method of FSK or DTMF. The method is chosenaccording to the exchange of telephone office. This unit is available to receive the data with both methods and displays thereceived data on LCD.•••• FSK (Frequency Shift Keying) format•••• DTMF formatIt is the method to send the telephone number of calling party with DTMF to the telephone. DTMF is sent before the first bellsignal.The data is sent in turn; first the start code, secondly the telephone number of calling party, lastly end code.The DTMF is chosen from A (1633Hz and 697Hz), B (1633Hz and 770Hz), C (1633Hz and 852Hz) and D (1633Hz and 941Hz)as the start code and end code according to the exchange.57KX-TG2480BXS / KX-TGA248BXS
