Some RS485 shields are already available for the Raspberry Pi on the market, but these extensions are not suitable for professional use, because they come without a galvanic isolation between the RS485 bus and the Raspberry Pi. Without such isolation a damaging of the Raspberry Pi or malfunction of the device is possible, because of the large distances of a RS485 bus. Furthermore a full-duplex mode (RS422) is also not integrated.
Our shield comes with a lot of additional features:
The RS485 is in use in many applications like industrial and home automation (for example MODBUS), lighting control (DMX), video surveillance (for example Pelco D) ...
If you like to know more about RS485 visit this website: http://www.radio-electronics.com/info/telecommunications_networks/rs485/rs-485-tutorial-basics.php