W90N745CD Datasheet, PDF (349/422 Pages) Winbond – 16/32-bit ARM microcontroller

W90N745CD/W90N745CDG
I²C Prescale Register 0/1 (I²C_DIVIDER 0 /1)
REGISTER
I²C_DIVIDER0
I²C_DIVIDER1
ADDRESS
0xFFF8_6004
0xFFF8_6104
R/W
R/W
R/W
DESCRIPTION
I²C Clock Prescale Register 0
I²C Clock Prescale Register 1
RESET VALUE
0x0000_0000
0x0000_0000
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
DIVIDER[15:8]
7
6
5
4
3
2
1
0
DIVIDER[7:0]
BITS
[15:0]
DIVIDER
DESCRIPTIONS
Clock Prescale Register
It is used to prescale the SCL clock line. Due to the structure of the I²C
interface, the core uses a 5*SCL clock internally. The prescale register must
be programmed to this 5*SCL frequency (minus 1). Change the value of the
prescale register only when the “I²C_EN” bit is cleared.
Example: pclk = 32MHz, desired SCL = 100KHz
prescale = ^{32 MHz} − 1 = 63 ( dec ) = 3 F ( hex )
5 ∗ 100 KHz
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