[Introduction]：E810-U21S is an industrial-grade USB to 2-way RS485 conversion module. With an external USB interface, you can convert 2 independent RS485 interfaces without affecting each other. It is suitable for scenarios where the computer is connected to multiple RS485 networks at the same time. Built-in RS485 automatic transceiver switching circuit, independent pin control switching, making RS485 communication more reliable and able to connect more devices at the same time. It can convert single-ended USB signals into RS-485 signals without external power supply.