Abstract: A power source device of an expansion unit determines whether an electric device is connected to the expansion unit, and supplies an operating power source voltage CC to the electric device only when the electric device is connected to the expansion unit. Further, the power source device outputs a preset command to the electric device, and supplies a charging power source voltage B-CC to the electric device in accordance with device kind indicating information output from the electric device in response to the preset command. Also, when the power supply device of the expansion unit is in an abnormal state, the power supply device of the expansion unit detects the abnormal state, and outputs the electric device to a state signal representing the abnormal state and execute power source interruption processing of the power source device. In the electric device, power source interruption processing of a power source device of the electric device is performed in response to the state signal.

Abstract: A function expanding apparatus for a compact electronic device includes a casing having a supporting portion and a supporting plate attached to the casing to be movable in a predetermined direction. A pair of retaining portions are formed on the supporting plate. The rear portion of the electronic device is mounted on the supporting portion and is positioned in its width direction by a pair of positioning members provided at the supporting portion. The front end portion of the electronic device is mounted on the supporting plate and the retaining portions engage the front edge of the electronic device so as to restrain the movement of the electronic device in the depth direction thereof. The position of the retaining portion is adjusted by moving the supporting plate, in accordance with the depth of the mounted electronic device.

Abstract: A function expanding apparatus for electronic devices having a mechanism for supporting a connector body. Two elastic members hold a connector body which is freely slidable between the two elastic members. The connector body is movable in multiple directions so as to connect to the electronic apparatus.

Abstract: In a battery-driven computer system, a flip-flop circuit selects one of two switches for switching a power supply to the computer system in accordance with the terminal voltages of batteries detected by detecting circuits. When the first switch is switched on, the first battery coupled to the first switch supplies its power to the computer system. In this case, the second switch is switched off and the power from the second battery coupled to the second switch is not supplied to the computer system. When the terminal voltage of the first battgnal representing the power condition of the batteries.