HF2221 serial server user manual, introduces the features and characteristics of the product, including support for TCP/IP/Telnet /Modbus TCP protocol, support 2 RS232/RS422/RS485 to Wi-Fi/Ethernet data transmission, serial rate up to 230400 bps, support wireless work STA/AP/AP+STA, support routing/bridging mode network architecture, support 2 Ethernet interfaces, support web and PC software simple configuration, support data TLS/AES/DES3 security encryption configuration, support web OTA wireless upgrade, wide voltage 5~36VDC power