37.6.11 Loop-Back Mode

For debugging purposes, the I²S can be configured to loop back the Transmitter to the Receiver. Writing a '1' to the Loop-Back Test Mode bit in the Rx Serializer Control register (RXCTRL.RXLOOP) will connect SDO to SDI, so that transmitted data is also received.

Writing RXCTRL.RXLOOP=0 will restore the normal behavior and connection between Receive Serializer and SDI pin input. As for other changes to the Serializers configuration, the Receive Serializer must be disabled before writing the TXCTRL register to update TXCTRL.RXLOOP.