| 摘要 |
<p>PROBLEM TO BE SOLVED: To keep the deviation between the clock of a slave device and that of a master device within a desired time range in a system in which the master device and slave device are connected to each other through a circuit network using the D channel of the ISDN. SOLUTION: The master device M transmits a packet to the slave device S at decided timing by regarding the existing time as reference time. Upon receiving the reference time, the slave device S starts to count time from the received reference time and, at the same time, returns the received reference time to the master device M. Upon receiving the reference time from the slave device S, the master device M finds the transmitting time and, when the transmitting time is shorter than allowable time, instructs the slave device S to execute time correction. Consequently, the slave device S adopts the clock counting the time from the reference time as a new clock.</p> |
