| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the manufacture cost of a circuit board and to reduce the useless consumption of power. SOLUTION: When power is supplied to a device 2, an oscillation circuit 4 outputs a clock pulse 15. The control circuit 5 inputs the clock pulse 15, and outputs the clock pulse 15 when a system 3 requires the function of the circuit substrate 1. When the system 3 does not require the function of the circuit substrate 1, the signal 16 of a prescribed level is outputted. A substrate slot 6 supplies a signal outputted from the control circuit 5. The circuit substrate 1 receives the clock pulse 15 or the signal 16 of the prescribed level and divides a frequency at a frequency division ratio which is previously decided by a frequency fluctuation circuit 7. An execution circuit 8 executes the previously decided function which the circuit substrate 1 has when the clock pulse 15 which is frequency-divided is inputted. When the signal 16 of the prescribed level is inputted, the previously decided function which the circuit substrate 1 has is not executed.</p> |
