TTL to RS485 Serial Port UART Hardware Automatic Flow Control 3.3V/5.0V Module,Flow Control 3.3V/5.0V Module TTL to RS485 Serial Port UART Hardware Automatic, high EMC, EMI performance, long-distance transmission in the field, the module "access to the earth" side access to the earth, can play well The anti-interference and lightning protection of the role of the 485 bus more secure; indoor short-distance transmission can not access the earth,(1) This module fully considered the 485 bus lightning protection design and anti-jamming design, Automatic Flow Control 3.3V/5.0V Module TTL to RS485 Serial Port UART Hardware.