RS-485 Arduino Module

The modules operate from a standard 5V power supply and use 5V logic levels allowing them to be interfaced to the hardware serial ports of microcontrollers such as Arduino/PIC etc. The direction of communication can be controlled with just one digital pin (see diagram). It is also possible to connect multiple modules together for communication between 2 or more devices. For even greater distances two modules can be configured as a repeater.

Each module contains one driver and one receiver. Drivers are short-circuited current limited and are protected against excessive power dissipation by thermal shutdown circuitry that places the driver outputs into a high-impedance state. The receiver input has a fail-safe feature that guarantees a logic-high output if the input is open circuit.