Atmel Evaluation Kit for AT32uC3A0512, 32-Bit AVR Microcontroller Atmel ATEVK1105 ATEVK1105 Data Sheet
Product codes
ATEVK1105
244
AT32UC3A
24.13.7
Reversal after a Repeated Start
24.13.7.1
Reversal of Read to Write
The master initiates the communication by a read command and finishes it by a write command.
describes the repeated start + reversal from Read to Write mode.
Figure 24-28.
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.
24.13.7.2
Reversal of Write to Read
The master initiates the communication by a write command and finishes it by a read com-
mand.
describes the repeated start + reversal from Write to Read
mode.
Figure 24-29.
Repeated Start + Reversal from Write to Read Mode
Notes: 1. In this case, if 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
A
DATA0
A
DATA1
SADR
Sr
NA
W
A
DATA2
A
DATA3
A
P
Cleared after read
DATA0
DATA1
DATA2
DATA3
SVACC
SVREAD
TWD
TWI_THR
TWI_RHR
EOSACC
TXRDY
RXRDY
TXCOMP
As soon as a START is detected
S
SADR
W
A
DATA0
A
DATA1
SADR
Sr
A
R
A
DATA2
A
DATA3
NA
P
Cleared after read
DATA0
DATA2
DATA3
DATA1
TXCOMP
TXRDY
RXRDY
As soon as a START is detected
Read TWI_RHR
SVACC
SVREAD
TWD
TWI_RHR
TWI_THR
EOSACC
32058K AVR32-01/12