PURPOSE: To prevent the data collection of a program or the like at a controller side from being changed regardless of increase/decrease in a terminal equipment in a signal transmitter formed by connecting plural terminal equipments to a controller.
CONSTITUTION: The transmitter is provided with a power supply means 23A supplying power supply periodically to a controller 11 and a current supply gate 22. Then a terminal equipment controls a current supplied from transmission lines L1, L2 based on an address set by an address setting circuit and a switch output of a detected medium every time power supply is supplied sequentially. The controller 11 controls the current into a voltage and comparators 25, 26 make discrimination. Then a discrimination means 23B discriminates a binary signal and an identification means 23C identifies the address and data to collect data from the terminal equipment.
OKUNO HIROYUKI
YAMAMOTO SABURO
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