STA326
6.4 READ OPERATION
6.4.1 Current Address Byte Read
Following the START condition the master sends a device select code with the RW bit set to 1. The
STA326 acknowledges this and then responds by sending one byte of data. The master then terminates
the transfer by generating a STOP condition.
6.4.1.1Current Address Multi-byte Read
The multi-byte read modes can start from any internal address. Sequential data bytes will be read from
sequential addresses within the STA326. The master acknowledges each data byte read and then gen-
erates a STOP condition terminating the transfer.
6.4.2 Random Address Byte Read
Following the START condition the master sends a device select code with the RW bit set to 0. The
STA326 acknowledges this and then the master writes the internal address byte. After receiving, the in-
ternal byte address the STA326 again responds with an acknowledgement. The master then initiates an-
other START condition and sends the device select code with the RW bit set to 1. The STA326
acknowledges this and then responds by sending one byte of data. The master then terminates the trans-
fer by generating a STOP condition.
6.4.2.1Random Address Multi-byte Read
The multi-byte read modes could start from any internal address. Sequential data bytes will be read from
sequential addresses within the STA326. The master acknowledges each data byte read and then gen-
erates a STOP condition terminating the transfer.
6.5 Write Mode Sequence
Figure 9. I2C Write Procedure
ACK
ACK
ACK
ACK
ACK
ACK
BYTE
WRITE
DEV-ADDR
SUB-ADDR
SUB-ADDR
DATA IN
DATA IN
START
START
RW
RW
STOP
ACK
MULTIBYTE
WRITE
DEV-ADDR
DATA IN
STOP
6.6 Read Mode Sequence
Figure 10. I2C Read Procedure
ACK
NO ACK
CURRENT
ADDRESS
READ
DEV-ADDR
DEV-ADDR
DEV-ADDR
DEV-ADDR
DATA
SUB-ADDR
DATA
START
START
START
START
RW
ACK
STOP
ACK
ACK
ACK
ACK
NO ACK
RANDOM
ADDRESS
READ
DEV-ADDR
DATA
RW
RW=
START
RW
STOP
STOP
ACK
ACK
NO ACK
HIGH
SEQUENTIAL
CURRENT
READ
DATA
DATA
DATA
ACK
ACK
ACK
ACK
NO ACK
SEQUENTIAL
RANDOM
READ
SUB-ADDR
DEV-ADDR
DATA
DATA
RW
START
RW
STOP
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STMICROELECTRONICS [ ST ]
