| 摘要 |
PURPOSE:To attain the measurement with less error in a retention time of the hardware and software devices by incorporating a retention time measuring circuit to an exchange. CONSTITUTION:The retention time measuring device 5 is provided in a central controller (CC) of an electronic exchange. When a device number of an object device trunk TRK3 for measuring retention time is inputted to a registration circuit REG8, the REG8 registers it. When a subscriber telephone set A1 makes a call, the A1 is connected to the TRK3. When the TRK3 (ORT in this case) receives a calling number, an acquisition circuit HUNT10 transmits the acquired device number to an operation start time storage circuit STT12. The STT12 transmits it to a calculation circuit CAL21 as the read operation start time of a counter circuit CLK14. When the ORT completes the reception of the calling number, the ORT is released by an opening circuit IDL16 and the count value of the CLK14 is transmitted to the CAL21 as the operating end time. Thus, the retention time is calculated. |
