ELECTRONIC EQUIPMENT, ITS CONTROL METHOD, AND STORAGE MEDIUM

摘要

PROBLEM TO BE SOLVED: To excellently connect a host and electronic equipment together by limiting the power supply to a connected device when the device exceeds the power supply permissible capacity of the electronic equipment. SOLUTION: A constitution descriptor acquires information regarding the detailed constitution of a connected universal serial bus(USB) device such as whether the device whose connection is detected by a device connection detecting means 23 needs to be supplied with electric power and the power consumption of the connected device. When the power consumption of the connected device is larger than the permissible capacity of power supply from the power source, the electric power which is large enough to drive the connected device cannot be supplied, so a digital camera (USB host) inhibits the connection of the device. Then the power supply started in a previously selected operation mode 'maximum current 100 mA operation mode' is stopped and a suspend operation mode based upon USB is entered. In this mode, the current supplied to a connected device is set to a small current value of up to 500 μA to minimize influence on the power source of the digital camera side.