This is a high-speed USB bus adapter module that realizes the function of USB to 8 TTL serial ports. It is used to expand the asynchronous serial port for the computer, or directly upgrade the ordinary serial port device or MCU to the USB bus. Built-in firmware, emulates the standard serial port, used to upgrade the serial port peripherals, or add additional serial ports through USB. The serial port application under the Windows operating system on the computer is fully compatible without modification. Supports Windows, Linux, Android, macos and other operating systems. Hardware full-duplex serial port, built-in independent transmit and receive buffer, communication baud rate supports 1200bps-6Mbps. The serial port supports 8 data bits, odd parity, even parity and no parity, and supports 1 or 2 stop bits. Each serial port has a built-in 2048-byte receive FIF0 and a 1024-byte transmit FIFO. Supports half-duplex, provides 4 TNOWs to indicate the serial port is sending status, which can be used to control RS485 transceiver switch. Supports RS232, RS485, RS422 and other interfaces through external level conversion devices. Indicator light: Red light: Connect USB, 3.3V power indicator light. Emerald green light: The computer driver has been successfully installed, and the emerald green light is on. Normal: It can be used only when both indicators are on. Colour:Black Material:PCB+Plastic Package Contents: 1 x USB to TTL Serial Port Module