46.6.5.8 Alternative Command
In Client mode, Alternative Command mode is useful when SMBus mode is enabled to send or check the PEC byte.
Alternative Command mode is enabled by setting the ACMEN bit of the TWIHS Control Register and the transfer is configured in TWIHS_ACR.
For a combined transfer with PEC, only TWIHS_ACR.NPEC must be set, as the PEC byte is sent once at the end of the frame.
See Client Read Write Flowcharts for detailed flowcharts.