232 Two-way Optical Fiber Loop Network System with RS232C Interface

摘要

PURPOSE: A two-way optical loop network system using RS232C communication is provided to carry out a relay function without data analysis at a terminal device side. CONSTITUTION: A terminal device(400a) and a terminal access device(300a) comprise two channels respectively. The terminal device(400a) outputs the first transmit request signal(RTS1) and the second transmit request signal(RTS2) through its own channels(Ch1,Ch2). The first transmit request signal output part and the second transmit request signal output part are respectively connected with the first relay circuit part(500) and the second relay circuit part(510). The first relay circuit part(500) is composed of the first diode(D1), the first resistor(R1), the first relay(SW1), and the second relay(SW2). The first diode(D1), of which the cathode is connected with the first transmit request signal output part, is operated according to the first transmit request signal(RTS1). The first resistor(R1) is connected with the anode of the first diode(D1) and the first power terminal(V1). The first and second relays(SW1,SW2) are switched according to the operations of the first diode(D1).