AT32UC3L064_1 Datasheet, PDF (494/825 Pages) ATMEL Corporation – AVR32 32-bit Microcontroller

AT32UC3L
5. Wait until SR.TXRDY==1, then write third data byte to transfer to THR.
6. Wait until SR.TXRDY==1, then write fourth data byte to transfer to THR.
22.8.7.2
Read Followed by Read
Consider the following transfer:
START, DADR+R, DATA+A, DATA+NA, REPSTART, DADR+R, DATA+A, DATA+NA, STOP.
To generate this transfer:
1. Program CMDR with START=1, STOP=0, DADR, NBYTES=2 and READ=1.
2. Program NCMDR with START=1, STOP=1, DADR, NBYTES=2 and READ=1.
3. Wait until SR.RXRDY==1, then read first data byte received from RHR.
4. Wait until SR.RXRDY==1, then read second data byte received from RHR.
5. Wait until SR.RXRDY==1, then read third data byte received from RHR.
6. Wait until SR.RXRDY==1, then read fourth data byte received from RHR.
If combining several transfers, without any STOP or REPEATED START between them,
remember to set the ACKLAST bit in CMDR to keep from ending each of the partial transfers
with a NACK.
22.8.7.3
Write Followed by Read
Consider the following transfer:
START, DADR+W, DATA+A, DATA+A, REPSTART, DADR+R, DATA+A, DATA+NA, STOP.
Figure 22-12. Combining a Write and Read Transfer
TWI_THR
DATA0
DATA1
TWD
S ADR W A DATA0 A DATA1 NA Sr ADR R A DATA2 A DATA3 A P
TWI_RHR
TXRDY
RXRDY
DATA2
DATA3
TCOMP
22.8.7.4
To generate this transfer:
1. Program CMDR with START=1, STOP=0, DADR, NBYTES=2 and READ=0.
2. Program NCMDR with START=1, STOP=1, DADR, NBYTES=2 and READ=1.
3. Wait until SR.TXRDY==1, then write first data byte to transfer to THR.
4. Wait until SR.TXRDY==1, then write second data byte to transfer to THR.
5. Wait until SR.RXRDY==1, then read first data byte received from RHR.
6. Wait until SR.RXRDY==1, then read second data byte received from RHR.
Read Followed by Write
Consider the following transfer:
32099A–AVR32–06/09
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