![](http://datasheet.mmic.net.cn/90000/MC80C32E-12-883-D_datasheet_2371307/MC80C32E-12-883-D_228.png)
228
8272E–AVR–04/2013
ATmega164A/PA/324A/PA/644A/PA/1284/P
Figure 21-14. Formats and states in the Master Receiver mode.
21.7.3
Slave Receiver mode
In the Slave Receiver mode, a number of data bytes are received from a Master Transmitter
(see
Figure 21-15). All the status codes mentioned in this section assume that the prescaler bits
are zero or are masked to zero.
Figure 21-15. Data transfer in Slave Receiver mode.
To initiate the Slave Receiver mode, TWAR and TWCR must be initialized as follows:
S
SLA
R
A
DATA
A
$08
$40
$50
SLA
R
$10
AP
$48
A or A
$38
Other master
continues
$38
Other master
continues
W
A
$68
Other master
continues
$78
$B0
To corresponding
states in slave mode
MR
MT
Successfull
reception
from a slave
receiver
Next transfer
started with a
repeated start
condition
Not acknowledge
received after the
slave address
Arbitration lost in slave
address or data byte
Arbitration lost and
addressed as slave
DATA
A
n
From master to slave
From slave to master
Any number of data bytes
and their associated acknowledge bits
This number (contained in TWSR) corresponds
to a defined state of the Two-Wire Serial Bus. The
prescaler bits are zero or masked to zero
P
DATA
A
$58
A
RS
TWAR
TWA6
TWA5
TWA4
TWA3
TWA2
TWA1
TWA0
TWGCE
value
Device’s Own Slave Address
Device 3
Device n
SDA
SCL
........
R1
R2
V
CC
Device 2
MASTER
TRANSMITTER
Device 1
SLAVE
RECEIVER