| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To allow both a host device and a device unit to enter normal mode from power-saving mode or restore the normal mode from the power-saving mode without reducing user convenience, and to reduce power consumption of the device unit. <P>SOLUTION: The operation unit 1 including a main controller 100 and an operation panel 200 connected communicably by a USB interface 300 including a power supply line 301 includes: a power supply monitoring part 204 for monitoring a power supply voltage of the power supply line 301; and an OR circuit 205, a switching circuit 206 and a switching circuit 210 for switching between the normal mode and the power-saving mode on the basis of a monitoring result by the power supply monitoring part 204. An OR circuit 205, the switching circuit 206 and the switching circuit 210 stop the supply of power supply voltage of a control part 201, a USB controller 202 and an operation display part 211 upon switching from the normal mode to the power saving mode. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
