| 摘要 |
PURPOSE:To prevent the lowering of the switching capability of a central processing unit, by controlling the greater part of the sending of charging pulses against servicing communication lines with a monitoring signal transmitting device. CONSTITUTION:A central processing unit CC changes a monitoring signal SS stored in an address corresponding to a communication line, from which a response from a called subscriber is detected, of a line condition memory SSM in a monitoring signal transmitting device SSS, from ''1'' to ''0'', and when a charging pulse P is to be sent to said communication line, a charging signal ACT1 and initial values of a timer value TC and a remaining timer value WK are stored in appropriate addresses of control memories CM1, CM2, and CM3 respectively. Therefore, in the monitoring signal transmitting device SSS, a charging pulse cycle generating circuit PT2 scans the control memory CM1 at a prescribed operational cycle and autonomously sends the charging pulse P. |
