A portable game machine comprising:
- a game machine housing;
- a game drive circuit for activating a game;
- a game control circuit for issuing a control signal for activating a game;
- a high-power short-life first power supply serving as a battery for activating the game drive circuit and the game control circuit;
- and
- a low-power long-life second power supply serving as a battery for activating the game drive circuit and the game control circuit, the game machine housing being configured to prevent access to the second power supply without the use of a tool;
- the portable game machine further comprising:
- a power switch for turning on or off power supply to the game drive circuit from the first power supply;
- and
- a power management system for controlling a power supply channel from the first power supply and a power supply channel from the second power supply, the power management system having the function of performing control operation (I) indispensably and at least one control operation selected from the group consisting of (ii), (iii), (iv), and (v):
- (i) an operation for, in principle, supplying power to the game drive circuit from the first power supply, as well as for supplying power to the game control circuit from the first power supply when the first power supply has sufficient power supply ability and supplementally supplying power from the second power supply;
- (ii) an operation for supplying power to the game control circuit from the first power supply, when it is detected that the power supply capability of the second power supply has dropped to a predetermined level or lower;
- (iii) an operation for preventing power supply to the game control circuit from the second power supply even though the power switch is turned on, when it is detected that the power supply capability of the first power supply has dropped to a predetermined level or lower;
- (iv) an operation for preventing power supply to the game drive circuit from the first power supply without involvement of power supply to the game control circuit from the second power supply when it is detected that the power supply capability of the first power supply has dropped to a predetermined level or lower, as well as for preventing power supply to the game control circuit from the second power supply even though the power switch is turned on;
- and
- (v) an operation for supplying power supply to the game drive circuit from the first power supply when runaway of a control circuit provided within circuitry is detected.