RS422 to TTL/UART/MCU Serial Port Signal Mutual Module with Over-Voltage Over-Current Protection-3.3V
VCC: + 3.3V
TXD : The module's TTL (UART) to send, connected to the microcontroller's RXD receiver pin;
RXD : The module's TTL (UART) receiver, connected to the microcontroller TXD send pin;
GND : The module ground wire (this wire must be connected with the ground wire of microcontroller system);