Figure 21-16. Formats and States in the Slave Receiver Mode
Reception of the own
S
SLA
W
A
DATA
A
DATA
A
P or S
slave address and one or
more data bytes. All are
acknowledged
$60
$80
$80
A
$A0
Last data byte received
is not acknowledged
P or S
$88
Arbitration lost as master
and addressed as slave
A
$68
A
Reception of the general call
address and one or more data
bytes
General Call
DATA
A
DATA
A
P or S
$70
$90
$90
A
$A0
Last data byte received is
not acknowledged
P or S
$98
Arbitration lost as master and
addressed as slave by general call
A
$78
Any number of data bytes
and their associated acknowledge bits
From master to slave
From slave to master
DATA
A
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
n
21.7.4
Slave Transmitter Mode
In the Slave Transmitter mode, a number of data bytes are transmitted to a Master Receiver
(see Figure 21-17). All the status codes mentioned in this section assume that the prescaler bits
are zero or are masked to zero.
Figure 21-17. Data Transfer in Slave Transmitter Mode
VCC
Device 1
SLAVE
TRANSMITTER
Device 2
MASTER
RECEIVER
Device 3
Device n
R1
R2
........
SDA
SCL
232
ATmega48/88/168
2545M–AVR–09/07
ATMEL [ ATMEL ]
