63.7.11.7.1 TXRDY and RXRDY Configuration

The TXRDY flag indicates if one or more data can be written in the FIFO depending on the configuration of FLEX_US_FMR.TXRDYM/RXRDYM.

As an example, if a word (32-bit) is written in FLEX_US_THR, the TXRDYM field must be configured so that the TXRDY flag is at ‘1’ only when at least four data can be written in the Transmit FIFO.

In the same way, if a word (32-bit) is read in FLEX_US_RHR, the RXRDYM field must be configured so that the RXRDY flag is at ‘1’ only when at least four unread data are in the Receive FIFO.