Data communication apparatus

摘要

A data communication apparatus in which if it is determined that a distant station presently in communication is a called station by a distant-station discriminating means, and a call-waiting signal is detected by a call-waiting-signal detecting means, a call-waiting-telephone controlling means is activated. This call-waiting-telephone controlling means switches over the line to the interrupting-station side by controlling a line switching means, and commences processing for an interrupt communication by a call-waiting telephone. Thereby, even if there has been an interrupt request signal, an interrupt communication is not allowed if a distant station presently in communication is in a chargeable state.