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CHAPTER 16 SERIAL INTERFACE IICA
User’s Manual U19780EJ2V0UD
446
16.5.2 Addresses
The address is defined by the 7 bits of data that follow the start condition.
An address is a 7-bit data segment that is output in order to select one of the slave devices that are connected to
the master device via the bus lines. Therefore, each slave device connected via the bus lines must have a unique
address.
The slave devices include hardware that detects the start condition and checks whether or not the 7-bit address
data matches the data values stored in the slave address register 0 (SVA0). If the address data matches the SVA0
values, the slave device is selected and communicates with the master device until the master device generates a
start condition or stop condition.
Figure 16-15. Address
SCLA0
SDAA0
INTIICA0
1
2
3
4
5
6
7
8
9
A6
A5
A4
A3
A2
A1
A0
R/W
Address
Note
Note
INTIICA0 is not issued if data other than a local address or extension code is received during slave device
operation.
Addresses are output when a total of 8 bits consisting of the slave address and the transfer direction described in
16.5.3 Transfer direction specification
are written to the IICA shift register (IICA). The received addresses are
written to IICA.
The slave address is assigned to the higher 7 bits of IICA.
16.5.3 Transfer direction specification
In addition to the 7-bit address data, the master device sends 1 bit that specifies the transfer direction.
When this transfer direction specification bit has a value of “0”, it indicates that the master device is transmitting
data to a slave device. When the transfer direction specification bit has a value of “1”, it indicates that the master
device is receiving data from a slave device.
Figure 16-16. Transfer Direction Specification
SCLA0
SDAA0
INTIICA0
1
2
3
4
5
6
7
8
9
A6
A5
A4
A3
A2
A1
A0
R/W
Transfer direction specification
Note
Note
INTIICA0 is not issued if data other than a local address or extension code is received during slave device
operation.