NuMicro® NUC029LEE/NUC029SEE
32-bit Arm
®
Cortex
®
-M0 Microcontroller
Aug, 2018
Page
141
of
497
Rev 1.00
N
U
MICRO
®
N
UC02
9L
E
E
/N
UC029
S
E
E
T
E
CHN
ICA
L R
E
F
E
R
E
NC
E
M
A
NU
A
L
Frequency Divider Control Register (FRQDIV)
Register
Offset
R/W
Description
Reset Value
FRQDIV
0x24
R/W
Frequency Divider Control Register
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
Reserved
7
6
5
4
3
2
1
0
Reserved
CLKO_1HZ_E
N
DIVIDER1
DIVIDER_EN
FSEL
Bits
Description
[31:7]
Reserved
Reserved.
[6]
CLKO_1HZ_EN
Clock Output 1Hz Enable Bit
0 = 1 Hz clock output for 32.768 kHz external low speed crystal oscillator clock frequency
compensation Disabled.
1 = 1 Hz clock output for 32.768 kHz external low speed crystal oscillator clock frequency
compensation Enabled.
[5]
DIVIDER1
Frequency Divider One Enable Bit
0 = Frequency divider will output clock with source frequency divided by FSEL.
1 = Frequency divider will output clock with source frequency.
[4]
DIVIDER_EN
Frequency Divider Enable Bit
0 = Frequency Divider function Disabled.
1 = Frequency Divider function Enabled.
[3:0]
FSEL
Divider Output Frequency Selection Bits
The formula of output frequency is
F
out
= F
in
/2
(N+1).
F
in
is the input clock frequency.
F
out
is the frequency of divider output clock.
N is the 4-bit value of FSEL[3:0].