| 摘要 |
<p>PURPOSE:To control the power supply of a terminal equipment with a small quantity of hardware by controlling the application of power supply of the terminal equipment after detection of a transmission start signal for data/control information and performing the power cut control of the terminal equipment in case the transmission start signal is not detected fro a fixed time. CONSTITUTION:The output signal of a communication controller 1 detects the start for the data and the control information sent via a start bit detecting circuit 5 after the level change and resets a flip-flop 7 and a counter 6. A counter 8 functions as a timer to set a flip-flop 9 after a delay of the count signal transmission time and also to start the counting action of a counter 10. The counter 10 sends the count output signal to shift register 11 as a pulse signal. The register 11 shifts the single side output signal of the flip-flop 9, and a driver circuit 12 instructs the application of power supply of a terminal equipment while the output signal of the flip-flop 9 is kept ON. Then the circuit 12 instructs the cut of power supply of the terminal equipment when the output signal of the flip-flop 9 is kept OFF. Thus it is possible to perform the power supply control of the terminal equipment connected to the controller 1 with use of a simple circuit.</p> |
