| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem in which in a deep sleep mode, a communication device cannot shift to a power off mode even if the communication device changes to a state unconnected with a network during the deep sleep mode because the communication device cannot detect connection with the network.SOLUTION: A communication device capable of connecting with and communicating through a plurality of lines and its control method shift the communication device to a deep sleep mode if a transition condition to the sleep mode is satisfied, clock a time the deep sleep mode is continuing, have the communication device return from the deep sleep mode when the clocked time reaches a prescribed time, and determine whether or not the communication device is connected with at least one of the plurality of lines. If they determine that the communication device is connected with at least one of the plurality of lines, they control the communication device not to turn off power but to shift to the deep sleep mode.SELECTED DRAWING: Figure 6 |
