Datasheet

197
ATmega48/88/168 Automotive [DATASHEET]
7530K–AVR–07/14
Figure 19-17. Formats and States in the Slave Receiver Mode
0xA0 A STOP condition or
repeated START condition
has been received while still
addressed as Slave
No action 0
0
1
1
0
0
0
0
1
1
1
1
0
1
0
1
Switched to the not addressed slave mode;
no recognition of own SLA or GCA
Switched to the not addressed slave mode;
own SLA will be recognized; GCA will be
recognized if TWGCE = “1”
Switched to the not addressed slave mode;
no recognition of own SLA or GCA;
a START condition will be transmitted when
the bus becomes free
Switched to the not addressed slave mode;
own SLA will be recognized; GCA will be
recognized if TWGCE = “1”;a START
condition will be transmitted when the bus
becomes free
Table 19-6. Status Codes for Slave Receiver Mode (Continued)
Status Code
(TWSR)
Prescaler
Bits are 0
Status of the 2-wire Serial
Bus and 2-wire Serial
Interface Hardware
Application Software Response
Next Action Taken by TWI Hardware
To/from TWDR To TWCR
STA STO TWINT TWEA
S
Reception of the own
slave address and one or
more data bytes. All are
acknowledged
Last data byte received
is not acknowledged
Last data byte received
is not acknowledged
Arbitration lost as master
and addressed as slave
Arbitration lost as master
and as slave by general call
From master to slave
Any number of data bytes
and their associated acknowledge bits
This number (contained in TWSR) corresponds
to a defined state of the 2-Wire Serial Bus.
The prescaler bits are zero or masked to zero
From slave to master
SLA W A DATAAP or S
A
DATA
ADATA
$60
$68
$80 $80 $A0
$88
A
P or SA
n
$90 $90 $A0
$98
P or SA
Reception of the general call
address and one or more
data bytes
A
$70
General Call DATAAP or S
A
DATA
$78
A