| 摘要 |
PROBLEM TO BE SOLVED: To suppress the time errors of all slave devices connected to a network within the range of the allowable time errors of respective devices. SOLUTION: A master device 1 and a slave device 3 are connected to each other through a network line 2. The device 3 is provided with a time management part 31 for outputting a time inquiry request signal to the master side, inputting a time inquiry response signal from the master side, measuring communication time from the output of the request signal up to the input of the response signal, and when the communication time is within a prescribed value at the time of comparing the time with past average communication time, outputting prescribed time setting information to set up the time of a clock part 30, a time statistic processing part 33 for calculating the average communication time from plural past communication time information data supplied from the time management part 31 and a transmission/reception managing part 32 for transmitting/receiving a time inquiry request signal/a time inquiry response signal. The device 1 is provided with a transmission/reception managing part 12 and a time management part 11 for reading out master side time from a clock part 10 at the time of receiving the time inquiry request signal and returning the read result as the time inquiry response signal. |
