Communications shield provides easy implementation of UART data transmission

Analog Devices EVAL-CN0416-ARDZ RS-485 Communications Shield is an isolated and non-isolated RS-485 transceiver board. This board provides easy implementation of asynchronous serial (UART) data transmission between multiple Arduino form factor systems or nodes, particularly over long distances. The circuit uses the ADM2682E RS-485 transceiver for isolated communications and the LTC2865 for non-isolated RS-485 communications. Either device can be configured to both full-duplex or half-duplex operation and with open or terminated transmission lines.

The circuit has onboard RJ-45 ports which enable the usage of the common CAT5 cable for fast physical wiring of nodes. The termination resistance is provided by default to the CAT5 cable characteristic impedance of 100Ohm but can be configured to support the standard RS485 cable impedance of 120Ohm. The cable also carries power supply lines which are by default unpowered but can be connected to a 3.3V supply from the board's low-dropout voltage regulator, ADP7102. The system has an onboard 10-pin connector compatible with the ADALM-UARTJTAG which provides for serial connections to a PC or other device.