RS-485 Transceiver Control

The hardware flow control can be used to control the direction of an RS-485 transceiver as shown in the following figure. The CTS input will be configured to be always enabled by setting the UxCTSPPS selection to an unimplemented PORT pin, such as RD0. When the signal and control lines are configured as shown in the figure below, the UART will not receive its own transmissions. To verify that there are no collisions on the RS-485 lines, the transceiver RE control can be disconnected from TXDE and tied low, thereby enabling loopback reception of all transmissions. See the Collision Detection section for more information.

Figure 1. RS-485 Configuration