Single-chip microcomputer TTL to RS485 module 485 to UART serial port Level conversion, automatic hardware control Unique network ID, 3.3V and 5.0V power supply RS485 signal perfectly compatible with automatic control module RXD, TXD signal indicator lights to monitor transmission and reception status Standard 2.54 pitch design for easy secondary development Color: Blue Material: Metal Operating Temperature: -40°C to +85°C Size: 42.8mm x 15.22mm x 0.8mm Industrial-grade chip and design for strong anti-interference and enhanced protection Suitable for industrial environments and harsh field conditions Recommended use within 800m with 2 x 1.5 cable; use repeaters for distances over 800m Half-hole process design with 0.8mm thickness, can be used on motherboards or soldered Includes 120 Ohm matching resistor for short-distance transmission Supports multi-machine communication, up to 128 devices on the bus Hot-pluggable module, prevents signal switch failure during hot-plugging Copper plating to prevent signal interference