18.2.7.2 SDA Hold Timeout

When using the I²C in slave mode, it will be important to set a SDA hold time which assures that the master will be able to pick up the bit sent from the slave. The SDA hold time makes sure that this is the case by holding the data line low for a given period after the negative edge on the clock.

The SDA hold time is also available for the master driver, but is not a necessity.