at91sam9260-cj ATMEL Corporation, at91sam9260-cj Datasheet - Page 401

• Manufacturer Part Number: at91sam9260-cj
• Description: At91 Arm Thumb Microcontrollers
• Manufacturer: ATMEL Corporation

Figure 31-20. Programmer Sends Data While the Bus is Busy
Figure 31-21. Arbitration Cases
401
Data from a Master
TWI DATA transfer
TWI DATA transfer
Data from TWI
(DADR + W + START + Write THR)
(DADR + W + START + Write THR)
AT91SAM9260
ARBLST
TWCK
A transfer is programmed
TWCK
TWD
TWD
A transfer is programmed
TWCK
TWD
Note:
The flowchart shown in
in Multi-master mode.
7. If TWI has to be set in Slave mode, wait until TXCOMP flag is at 1 and then program the
Slave mode.
S
S
S
In the case where the arbitration is lost and TWI is addressed, TWI will not acknowledge even if it
is programmed in Slave mode as soon as ARBLST is set to 1. Then, the Master must repeat
SADR.
DATA sent by a master
1
1
1
Transfer is stopped
Bus is busy
0 0
0
0 0
1
STOP sent by the master
Transfer is kept
1 1
1 1
TWI stops sending data
Arbitration is lost
Figure 31-22 on page 402
(DADR + W + START + Write THR)
Transfer is programmed again
Data from the master
Bus is busy
Transfer is kept
Bus is free
Bus is considered as free
Transfer is initiated
P
P
Bus is free
gives an example of read and write operations
Bus is considered as free
Transfer is initiated
START sent by the TWI
S
S
S
1
1
1
0
0 0
0
DATA sent by the TWI
1
0
The master stops sending data
1 1
1 1
Arbitration is lost
6221G–ATARM–31-Jan-08
Data from the TWI