
M0A21/M0A23 Series
May 06, 2022
Page
201
of 746
Rev 1.02
M0
A21
/M
0
A
2
3
SE
RIES
TEC
H
NICAL
RE
FEREN
C
E
M
ANUAL
Clock Status Monitor Register (CLK_STATUS)
The bits in this register are used to monitor if the chip clock source is stable or not, and whether the
clock switch is failed.
Register
Offset
R/W
Description
Reset Value
CLK_STATUS
0x50
R
Clock Status Monitor Register
0x0000_00XX
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
CLKSFAIL
Reserved
HIRCSTB
LIRCSTB
Reserved
LXTSTB
HXTSTB
Bits Description
[31:8]
Reserved
Reserved.
[7]
CLKSFAIL
Clock Switching Fail Flag (Read Only)
This bit is updated when software switches system clock source. If switch target clock is stable, this bit will be
set to 0. If switch target clock is not stable, this bit will be set to 1.
0 = Clock switching success.
1 = Clock switching failure.
Note:
Write 1 to clear the bit to 0.
[6:5]
Reserved
Reserved.
[4]
HIRCSTB
HIRC Clock Source Stable Flag (Read Only)
0 = Internal high speed RC oscillator (HIRC) clock is not stable or disabled.
1 = Internal high speed RC oscillator (HIRC) clock is stable and enabled.
[3]
LIRCSTB
LIRC Clock Source Stable Flag (Read Only)
0 = Internal low speed RC oscillator (LIRC) clock is not stable or disabled.
1 = Internal low speed RC oscillator (LIRC) clock is stable and enabled.
[2]
Reserved
Reserved.
[1]
LXTSTB
LXT Clock Source Stable Flag (Read Only)
0 = External low speed crystal oscillator (LXT) clock is not stable or disabled.
1 = External low speed crystal oscillator (LXT) clock is stabled and enabled.
[0]
HXTSTB
HXT Clock Source Stable Flag (Read Only)
0 = External high speed crystal oscillator (HXT) clock is not stable or disabled.
1 = External high speed crystal oscillator (HXT) clock is stable and enabled.