GD32VF103 User Manual
74
0xxx: CK_SYS selected
1000: (CK_SYS / 2) selected
1001: (CK_SYS / 4) selected
1010: (CK_SYS / 8) selected
1011: (CK_SYS / 16) selected
1100: (CK_SYS / 64) selected
1101: (CK_SYS / 128) selected
1110: (CK_SYS / 256) selected
1111: (CK_SYS / 512) selected
3:2
SCSS[1:0]
System clock switch status
Set and reset by hardware to indicate the clock source of system clock.
00: select CK_IRC8M as the CK_SYS source
01: select CK_HXTAL as the CK_SYS source
10: select CK_PLL as the CK_SYS source
11: reserved
1:0
SCS[1:0]
System clock switch
Set by software to select the CK_SYS source. Because the change of CK_SYS has
inherent latency, software should read SCSS to confirm whether the switching is
complete or not. The switch will be forced to IRC8M when leaving Deep-sleep and
Standby mode or HXTAL failure is detected by HXTAL clock monitor when HXTAL
is selected directly or indirectly as the clock source of CK_SYS
00: select CK_IRC8M as the CK_SYS source
01: select CK_HXTAL as the CK_SYS source
10: select CK_PLL as the CK_SYS source
11: reserved
5.3.3.
Clock interrupt register (RCU_INT)
Address offset: 0x08
Reset value: 0x0000 0000
This register can be accessed by byte(8-bit), half-word(16-bit) and word(32-bit)
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
Reserved
CKMIC
PLL2
STBIC
PLL1
STBIC
PLL
STBIC
HXTAL
STBIC
IRC8M
STBIC
LXTAL
STBIC
IRC40K
STBIC
w
w
w
w
w
w
w
w
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Reserved
PLL2
STBIE
PLL1
STBIE
PLL
STBIE
HXTAL
STBIE
IRC8M
STBIE
LXTAL
STBIE
IRC40K
STBIE
CKMIF
PLL2
STBIF
PLL1
STBIF
PLL
STBIF
HXTAL
STBIF
IRC8M
STBIF
LXTAL
STBIF
IRC40K
STBIF
rw
rw
rw
rw
rw
rw
rw
r
r
r
r
r
r
r
r