Carefully optimised circuitry for communication rates up to 12Mbps TTL compatible 5V level On-board DC5V power supply interface, 500MA current output, improve load capacity On-board, can be configured to JRAG/SPI and other interface forms through FTPROG software All available I0 are exported. Each serial port has an independent transceiver indicator LED, easy to observe the serial port status four serial ports are connected at the same time, you can observe the data at the same time VCC: power (5.0V); RXD: module comes with the port of the receiving pin (TTL level, can not be directly connected to the RS232 level!) Can be connected to the microcontroller's TXD; TXD: module comes with the port's receive pin (TTL level, can not be directly connected to the RS232 level!) Can be connected to the RXD of the microcontroller; GND: Ground Supply Voltage:Power(5.0V);Current:50MA;Baud Rate:1200-921600;Transmission Rate:12MBPS;Operating Temperature:-40 to 85；This is a 5V/3.3VTTL level Shen port, do not connect RS-232 level devices (+-5V to +-15V) This module USB power supply with a load shall not exceed 500mA, otherwise the module or the computer USB has the risk of overload damage (communication only GND/TX/RX three wires)