The Maximum Read Turnaround time is the time that the Controller will wait before reading
the data it requested for Private Transactions. This delay can be specified in the I3CxMRT
Maximum Read Turnaround register. This is useful when the user is expecting data read
delays for Private Read Transactions due to any reason. The Controller can be notified
of this delay by setting the BCR0 bit during setup, to signify that the device is speed-limited. After
the Controller reads the I3CxBCR register during the Dynamic Address Assignment process, the Controller can then read the I3CxMRT register by
using the Get Maximum Data Speed GETMXDS Common Command Code (CCC). Figure 1 below demonstrates an instance where the
Controller waits for the Maximum Read Turnaround time before reading data from the
Target.
Figure 1. Example Instance of Maximum Read
Turnaround Time
Important: The Controller can
choose to not wait for Maximum Read Turnaround time before attempting to read from the
Target. If the data is not available in the Transmit FIFO yet, then a Transmit Underrun
error is generated, the TXUIF interrupt flag is set, and the read request is NACKed in
which case the Controller will attempt to read again. Alternatively, the Target may have
the data ready to be read in the Transmit FIFO before the time reported. Refer to Transmit and Receive Buffers section for more information about Transmit Underrun error.