Atmel Evaluation Kit AT91SAM9M10-G45-EK AT91SAM9M10-G45-EK Data Sheet

Product codes
AT91SAM9M10-G45-EK
Page of 1361
 585
SAM9M10 [DATASHEET]
6355F–ATARM–12-Mar-13
32.11.6
TWI  Status  Register
Name: TWI_SR
Addresses:
0xFFF84020 (0), 0xFFF88020 (1)
Access: Read-only
Reset: 
0x0000F009
• TXCOMP:  Transmission  Completed  (automatically  set  /  reset)
TXCOMP used in Master mode: 
0 = During the length of the current frame.
1 = When both holding and shifter registers are empty and STOP condition has been sent.
TXCOMP behavior in Master mode
TXCOMP used in Slave mode:
0 = As soon as a Start is detected.
1 = After a Stop or a Repeated Start + an address different from SADR is detected.
TXCOMP behavior in Slave mode
.
• RXRDY:  Receive  Holding  Register  Ready  (automatically  set  /  reset)
0 = No character has been received since the last TWI_RHR read operation.
1 = A byte has been received in the TWI_RHR since the last read.
RXRDY behavior in Master mode
.
RXRDY behavior in Slave mode
 can be seen in 
.
• TXRDY:  Transmit  Holding  Register  Ready  (automatically  set  /  reset)
TXRDY used in Master mode:
0 = The transmit holding register has not been transferred into shift register. Set to 0 when writing into TWI_THR register.
1 = As soon as a data byte is transferred from TWI_THR to internal shifter or if a NACK error is detected, TXRDY is set at
the same time as TXCOMP and NACK. TXRDY is also set when MSEN is set (enable TWI).
TXRDY behavior in Master mode
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EOSACC
SCLWS
ARBLST
NACK
7
6
5
4
3
2
1
0
OVRE
GACC
SVACC
SVREAD
TXRDY
RXRDY
TXCOMP