Table 167. Status for Master Transmitter Mode
Application Software Response
To SSCON
SSSTO SSI
Status
Code Status of the TWI Bus
SSSTA and TWI Hardware
To/From SSDAT
SSSTA
SSAA Next Action Taken by TWI Hardware
A START condition has Write SLA+W
been transmitted
SLA+W will be transmitted.
X
08h
X
0
0
Write SLA+W
SLA+W will be transmitted.
X
X
X
0
0
0
0
A repeated START
condition has been
10h
Write SLA+R
transmitted
SLA+R will be transmitted.
X
Logic will switch to master receiver mode
Write data Byte
Data Byte will be transmitted.
X
0
1
0
0
0
1
0
0
0
No SSDAT action
SLA+W has been
Repeated START will be transmitted.
X
No SSDAT action
STOP condition will be transmitted and SSSTO flag
will be reset.
18h
20h
28h
transmitted; ACK has
been received
X
No SSDAT action
STOP condition followed by a START condition will
be transmitted and SSSTO flag will be reset.
1
1
0
X
Write data Byte
Data Byte will be transmitted.
X
0
1
0
0
0
1
0
0
0
No SSDAT action
SLA+W has been
Repeated START will be transmitted.
X
No SSDAT action
STOP condition will be transmitted and SSSTO flag
will be reset.
transmitted; NOT ACK
X
has been received
No SSDAT action
STOP condition followed by a START condition will
be transmitted and SSSTO flag will be reset.
1
1
0
X
Write data Byte
Data Byte will be transmitted.
X
0
1
0
0
0
1
0
0
0
No SSDAT action
Repeated START will be transmitted.
X
Data Byte has been
transmitted; ACK has
been received
No SSDAT action
STOP condition will be transmitted and SSSTO flag
will be reset.
X
No SSDAT action
STOP condition followed by a START condition will
be transmitted and SSSTO flag will be reset.
1
1
0
X
Write data Byte
Data Byte will be transmitted.
X
0
1
0
0
0
1
0
0
0
No SSDAT action
Repeated START will be transmitted.
X
Data Byte has been
transmitted; NOT ACK
No SSDAT action
STOP condition will be transmitted and SSSTO flag
will be reset.
30h
38h
X
has been received
No SSDAT action
STOP condition followed by a START condition will
be transmitted and SSSTO flag will be reset.
1
1
0
X
No SSDAT action
Arbitration lost in
TWI bus will be released and not addressed slave
mode will be entered.
0
1
0
0
0
0
X
SLA+W or data Bytes
No SSDAT action
A START condition will be transmitted when the bus
becomes free.
X
190
AT8xC51SND2C
4341D–MP3–04/05
ATMEL [ ATMEL ]
