Single chip microcomputer ,TTL turn RS485 module, 485 turn UART serial port, Level transfers, Hardware automatic flow control. 3.3V and 5.0V power supply, RS485 signal perfectly compatible with automatic flow control module. Without "Receive - launch" control, this module is as simple to use with your serial port operations.   Highlights: Compatible with 3.3V and 5.0V power supply. Compatible with 3.3V and 5.0V signal.(3) Absolute using imported chips; industrial design; anti-interference ability; while using more effective 485 lightning protection design can be used in the industrial field and harsh field environments; the working temperature of -40 to + 85 Degree Celsius ;transmission distance up to 1 kilometer (made with 850 meters of cable F1.5 tests recommended using in the 800 meters,when more than 800m please add repeaters). Semi-hole process design, thickness 0.8mm, can easily use as a picture board, it can also be welded terminal use. Has RXD, TXD signal indicator lights, monitor send and receive status.   Features: The module is fully considered lightning protection design,when long-distance transmission in the wild, the module "Connected to the ground" terminal is connected to the ground, can play a very good jamming and anti-lightning effect,so more secure; it can not connect with the ground when the indoor short-distance transmission. Using the standard 2.54 pitch design, easy to secondary development. Has a 120 ohm termination resistors, shorted R0 to enable the matching resistor. Support multi-machine communication, allowing access at up to 128 devices on the bus The module can be hot swapped, the signal does not appear dead phenomenon. A large area of copper to prevent signal interference.   Package list: 1 x TTL to RS485 Converter Module