... , zero delay automatic transmit Support EIA RS-232, RS-485 standard RS-232 signal TX , RX, GND RS-485 signal D+, D-, GND Asynchronism ... sense serial signal rate Support 128 point loopback RS-485 side 1200M (9600bps), RS-232 side less than 5M 600W surge protection ... power supply needed, powered from TXD, RTS, DTR signal in RS-232 port Consumption: Static consumption less than 20mA, dynamic consumption ...