... support for RXD, TXD, GND 3-line approach to work;RS422 support for RX-, RX +, TX-, TX + full-duplex mode;RS485 ... support for A, B half-duplex mode;RS422/485 Rate: 0-2M (optional 500K, 1M, 5M, 10M);Protection ... : RS422/485 with 600W sursge protection also has overload protection function. ...