the half hole process design, plate thickness 0.8 mm, can be easily as composite plate, can also be used for welding terminal; Has the RXD, TXD signal indicator lights, send and receive status panoramic view; Utilizes standard 2.54 pitch design; 120 ohm matching resistor, short R0 to enable matching resistor, shorting is recommended for long distance transmission; Supports multi-computer communication, allowing connection to a bus of up to 128 devices