| 摘要 |
PURPOSE:To register automatically a terminal kind to a terminal controller by applying a start from a 1st information transmission line or the 2nd information transmission line and detecting a response from the 2nd information transmission line or the 1st information transmission line. CONSTITUTION:When a non-telephone terminal connection presence signal is obtained from a phototransistor (PT) 1, a switch LSW(M) is turned on and a light emitting diode LED 5, a transformer T 3, a T line 31, a transformer T 1 and PT 7 form a closed circuit and a loop current flows. A terminal start signal LDET(S) is extracted from a photocoupler PC 5 by the current and a light emitting diode LED 4 is energized. A terminal controller start signal LDET(M) is extracted from the PT 6 of the photocoupler PC6. Then the registration sequence of inquiry/reply by terminal kind is attained between a terminal controller 1 and a non-telephone terminal 2 and the terminal kind is registered to the terminal controller 1.
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