ISD94100 Series Technical Reference Manual
Sep 9, 2019
Page
160
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Rev1.09
IS
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S
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C
HN
ICA
L
RE
F
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RE
NCE
M
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U
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Clock Source Select Control Register 2
(CLK_CLKSEL2)
Before clock switching, the related clock sources (pre-select and new-select) must be turned on.
Register
Offset
R/W Description
Reset Value
CLK_CLKSEL2
0x18
R/W Clock Source Select Control Register 2
0x0000_00A9
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
DPWMSEL
DMICSEL
Reserved
7
6
5
4
3
2
1
0
SPI2SEL
SPI1SEL
SPI0SEL
Reserved
PWM0SEL
Bits
Description
[31:14]
Reserved
Reserved. Any values read should be ignored. When writing to this field always write with
reset value.
[13:12]
DPWMSEL
DPWM Clock Source Selection
00 = Clock source from external high speed crystal oscillator (HXT).
01 = Clock source from PLL.
10 = Clock source from PCLK0.
11 = Clock source from internal high speed RC oscillator (HIRC).
[11:10]
DMICSEL
DMIC Clock Source Selection
00 = Clock source from external high speed crystal oscillator (HXT).
01 = Clock source from PLL.
10 = Clock source from PCLK1.
11 = Clock source from internal high speed RC oscillator (HIRC).
[9:8]
Reserved
Reserved. Any values read should be ignored. When writing to this field always write with
reset value.
[7:6]
SPI2SEL
SPI2 Clock Source Selection
00 = Clock source from external high speed crystal oscillator (HXT).
01 = Clock source from PLL.
10 = Clock source from PCLK0.
11 = Clock source from internal high speed RC oscillator (HIRC).
[5:4]
SPI1SEL
SPI1 Clock Source Selection
00 = Clock source from external high speed crystal oscillator (HXT).
01 = Clock source from PLL.
10 = Clock source from PCLK1.
