Datasheet

576
SAM9M10 [DATASHEET]
6355F–ATARM–12-Mar-13
32.10.5.7 Reversal after a Repeated Start
32.10.5.8 Reversal of Read to Write
The master initiates the communication by a read command and finishes it by a write command.
Figure 32-30 on page 576 describes the repeated start + reversal from Read to Write mode.
Figure 32-30. Repeated Start + Reversal from Read to Write Mode
1. TXCOMP is only set at the end of the transmission because after the repeated start, SADR is detected again.
32.10.5.9 Reversal of Write to Read
The master initiates the communication by a write command and finishes it by a read command.Figure 32-31 on
page 576 describes the repeated start + reversal from Write to Read mode.
Figure 32-31. Repeated Start + Reversal from Write to Read Mode
Notes: 1. In this case, if TWI_THR has not been written at the end of the read command, the clock is automatically stretched before
the ACK.
2. TXCOMP is only set at the end of the transmission because after the repeated start, SADR is detected again.
S SADR R ADATA 0A DATA1
SADRSr
NA
W A DATA 2 A DATA 3 A P
Cleared after read
DATA0 DATA 1
DATA2 DATA3
SVACC
SVREAD
TWD
TWI_THR
TWI_RHR
EOSACC
TXRDY
RXRDY
TXCOMP
As soon as a START is detected
S SADR W ADATA0A DATA 1
SADRSr
A
R A DATA2 A DATA 3 N A P
Cleared after read
DATA0
DATA2 DATA 3
DATA1
TXCOMP
TXRDY
RXRDY
As soon as a START is detected
Read TWI_RHR
SVACC
SVREAD
TWD
TWI_RHR
TWI_THR
EOSACC