3-in-1 serial port: RS-232, RS-422, or RS-485 Versatile operation modes including TCP Server, TCP Client, UDP, Ethernet Modem, and Pair Connection Real COM/TTY drivers for Windows and Linux 10M and 100M Ethernet speeds detected automatically 2-wire RS-485 with patented Automatic Data Direction Control (ADDC®) Built-in 15 KV ESD protection for all serial signals