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NUC126
Aug. 08, 2018
Page
365
of 943
Rev 1.03
NUC12
6 S
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CA
L R
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NCE
MA
NUA
L
I
2
C Status Register (I2C_STATUS)
Register
Offset
R/W Description
Reset Value
I2C_STATUS
0x0C
R
I
2
C Status Register 0
0x0000_00F8
31
30
29
28
27
26
25
24
Reserved
23
22
21
20
19
18
17
16
Reserved
15
14
13
12
11
10
9
8
Reserved
7
6
5
4
3
2
1
0
STATUS
Bits
Description
[31:8]
Reserved
Reserved.
[7:0]
STATUS
I
2
C Status
The three least significant bits are always 0. The five most significant bits contain the
status code. There are 28 possible status codes. When the content of I2C_STATUS is
F8H, no serial interrupt is requested. Others I2C_STATUS values correspond to defined
I
2
C states. When each of these states is entered, a status interrupt is requested (SI = 1). A
valid status code is present in I2C_STATUS one cycle after SI is set by hardware and is
still present one cycle after SI has been reset by software. In addition, states 00H stands
for a Bus Error. A Bus Error occurs when a START or STOP condition is present at an
illegal position in the formation frame. Example of illegal position are during the serial
transfer of an address byte, a data byte or an acknowledge bit.