XRA1203 Datasheet, PDF (5/17 Pages) Exar Corporation – 16-BIT I2C/SMBUS GPIO EXPANDER WITH RESET

REV. 1.0.0
1.1.1 I²C-bus Addressing
XRA1203
16-BIT I2C/SMBUS GPIO EXPANDER WITH RESET
There could be many devices on the I²C-bus. To distinguish itself from the other devices on the I²C-bus, the
XRA1203 has up to 16 I²C slave addresses using the A1-A0 address lines. Table 1 below shows the different
addresses that can be selected.
TABLE 1: I²C ADDRESS MAP
A1
SCL
SCL
SDA
SDA
SCL
SCL
SDA
SDA
GND
GND
VCC
VCC
GND
GND
VCC
VCC
A0
GND
VCC
GND
VCC
SCL
SDA
SCL
SDA
GND
VCC
GND
VCC
SCL
SDA
SCL
SDA
I²C ADDRESS
0x20 (0010 000X)
0x22 (0010 001X)
0x24 (0010 010X)
0x26 (0010 011X)
0x30 (0011 000X)
0x32 (0011 001X)
0x34 (0011 010X)
0x36 (0011 011X)
0x40 (0100 000X)
0x42 (0100 001X)
0x44 (0100 010X)
0x46 (0100 011X)
0x50 (0101 000X)
0x52 (0101 001X)
0x54 (0101 010X)
0x56 (0101 011X)
1.1.2 I²C Read and Write
A read or write transaction is determined by bit-0 of the slave address. If bit-0 is ’0’, then it is a write
transaction. If bit-0 is ’1’, then it is a read transaction.
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