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Post: Hi One method to get around the problem of switching the RS485 transceiver between transmit and receive is to use a transistor connected to the TX pin to switch the direction when the UART port is transmitting. We use this method on our RS485 Pi, you can find the [url=https://www.abelectronics.co.uk/docs/pdf/schematic-rs485pi.pdf]schematic for the board here[/url]. When transmitting the UART TX pin goes low causing the BSN20 transistor to switch off. This in turn sets the RE and DE pins on the RS485 transceiver high putting it into transmit mode. When the TX pin goes high the transistor switches on putting the RS485 transceiver into receive mode. On the RS485 Pi, we also included the option to use a separate GPIO 17 pin to control the direction by moving the 0R resistor from R6 to R7 but for the speeds supported by the SN65HVD72 transceiver, we found that switching the direction directly from the TX pin works adequately.