Method for indicating a communicating duration of an office line in a

Abstract

There is disclosed a method capable of indicating a communicating duration on a displaying means (LCD) of a key-phone upon a communication via the public telephone office line in a key-phone system. The method includes the steps of: a first process for driving a communicating duration starting timer and informing that communication is started; second process for initializing a buffer storing a communicating duration and driving the communicating duration increasing timer; third proces for driving said communicating duration increasing timer and then checking if it is in a state of a public telephone office line reserving, and terminating in a state of accumuating the communicating duration to a buffer; fourth process for producing present communicating duration data and transmitting the data to a key-phone; and fifth process for increasing a count value of communicating duration storing buffer, driving the communication increasing timer, and advancing to said third process.