| 摘要 |
<p>PURPOSE:To reduce the energy consumption of the device by providing a means for detecting the use condition of a bus and a means for managing power. CONSTITUTION:When there is an input from an I/O equipment 5 to an I/O control means 3 or when there is an interruption from an MPU 1 to each control means, a bus 2 is made busy and turned to an occupied state. In the state of not using the bus 2, the operations of the control means at one part and a peripheral equipment are not required. At such a time, it is detected at a power managing means by using a bus use condition detecting means 101 that each control means does not use the bus 2 or any specified circuit uses the bus. Then, a power supply control means 102 controls the supply of power to each control means and the peripheral equipment sets the device from a normal state to a low energy consumption state or reversely sets the device from the low energy consumption state to the normal state. Thus, the useless energy consumption can be reduced.</p> |
