| 摘要 |
PURPOSE:To reduce the power consumption, by making a current flow into the diode only when a data is transmitted, and reading a data of the terminal equipment, in the data transmission device for executing a remote inspection of the working amount. CONSTITUTION:When a clock pulse which is provided to the terminal A is in a high level, the voltage of the point E in the data gathering station 10 side becomes same as the supply voltage since the transistor Tr0 is turned off and a current does not flow to the terminal equipment 20 side. In case when the clock pulse is in a low level, the transistor Tr0 is turned on and a current flows to the terminal equipment 20 side, and therefore, the potential of the point E drops by the voltage drop portion of the resistor R0. Accordingly, a data of the terminal equipment 20 can be read by supervising the potential of the point E in the data gathering station 10. |
