DATA INFORMING METHOD AND COMMUNICATION INTERFACE DEVICE

PROBLEM TO BE SOLVED: To provide a communication interface device which can display previously registered telephone book data to a telephone set corresponding to busy information notice service connected to an analog port and can retrieve and display telephone book data with an operation from the telephone set. SOLUTION: An ISDN terminal adapter is provided with the analog port corresponding to pre-communication information notice service and busy information notice service and is provided with a function for writing telephone book data registered and edited by a computer through a data port to which the computer is connected and a function for reading data. In a data informing method, specified dial information transmitted from the telephone set connected to the analog port is detected and a data area which is previously written as telephone book data is retrieved. Telephone book data applied to specified dial information is noticed to an analog communication terminal connected to the analog port by busy information notice service.