63.9.5.4.6 SMBus Mode

SMBus mode is enabled when the FLEX_TWI_CR.SMEN bit is written to one. SMBus mode operation is similar to I²C operation with the following exceptions:

1. Only 7-bit addressing can be used.
2. The SMBus standard describes a set of timeout values to ensure progress and throughput on the bus. These timeout values must be programmed into FLEX_TWI_SMBTR.
3. Transmissions can optionally include a CRC byte, called Packet Error Check (PEC).
4. A set of addresses have been reserved for protocol handling, such as alert response address (ARA) and host header (HH) address. Address matching on these addresses can be enabled by configuring FLEX_TWI_CR appropriately.