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MS51
Dec. 17, 2019
Page
98
of 316
Rev 1.01
M
S51
SE
RIES
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CHNICA
L REF
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CE MA
NU
A
L
I2ADDR
– I
2
C Own Slave Address
Regiser
Address
Reset Value
I2ADDR
C1H, all pages
0000_0000b
7
6
5
4
3
2
1
0
I2ADDR[7:1]
GC
R/W
R/W
Bit
Name
Description
7:1
I2ADDR[7:1]
I
2
C device’s own slave address
In master mode:
These bits have no effect.
In slave mode:
These 7 bits define the slave address of this I
2
C device by user. The master should address
I
2
C device by sending the same address in the first byte data after a START or a repeated
START condition. If the AA flag is set, this I
2
C device will acknowledge the master after
receiving its own address and become an addressed slave. Otherwise, the addressing from
the master will be ignored.
Note that I2ADDR[7:1] should not remain its default value of all 0, because address 0x00 is
reserved for General Call.
6
GC
General Call bit
In master mode:
This bit has no effect.
In slave mode:
0 = The General Call is always ignored.
1 = The General Call is recognized if AA flag is 1; otherwise, it is ignored if AA is 0.