37.2.12.1 HDR Enter Pattern

When the Controller enters an HDR mode, it has a bus-wide effect and the whole I3C bus is configured in the selected HDR mode. Once entered, the HDR mode remains in effect until the end of the transaction.

The OPMD Operating Mode bits also change to reflect that the bus is operating in HDR mode (OPMD = 1x). While the bus is operating in HDR mode, the Start, Restart, and Stop bits (SCIF, RSCIF, and PCIF) become non-operational until the Target recognizes the HDR Exit Pattern and the bus starts to operate in SDR mode again.

To enter an HDR mode, the Controller broadcasts an Enter HDR Mode CCC (ENTHDR0 through ENTHDR7 CCCs). Even though the HDR modes and their corresponding CCCs are not supported by this Target module, the Target module detects when the Controller is entering an HDR mode and ignores all traffic on the bus until it detects an HDR Exit Pattern.