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CH32V003
Reference Manual
V1.3
19
0111: SYSCLK divided by 8.
1000: SYSCLK divided by 2.
1001: SYSCLK divided by 4.
1010: SYSCLK divided by 8.
1011: SYSCLK divided by 16.
1100: SYSCLK divided by 32.
1101: SYSCLK divided by 64.
1110: SYSCLK divided by 128.
1111: SYSCLK divided by 256.
Note: When the prescaler factor of the AHB clock source is
greater than 1, the prefetch buffer must be turned on.
[3:2]
SWS
RO
System clock (SYSCLK) status (hardware set).
00: the system clock source is HSI.
01: The system clock source is HSE.
10: The system clock source is a PLL.
11: Not available.
0
[1:0]
SW
RW
Select the system clock source.
00: HSI as system clock.
01: HSE as system clock.
10: PLL output as system clock.
11: Not available.
Note: With Clock Safe enabled (CSSON=1), HSI is forced
by hardware to be selected as the system clock when
returning from Standby and Stop mode or when the
external oscillator HSE used as the system clock fails.
0
3.4.3 Clock interrupt register (RCC_INTR)
Offset address: 0x04
31
30
29
28
27
26
25
24
23 22
21
20
19
18
17
16
Reserved
CS
SC Reserved
PLL
RDY
C
HSE
RDY
C
HSI
RDY
C
Reser
ved
LSI
RDY
C
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Reserved
PLL
RDYI
E
HSE
RDYI
E
HSI
RDYI
E
Reserv
ed
LSI
RDYIE
CS
SF Reserved
PLL
RDY
F
HSE
RDY
F
HSI
RDY
F
Reser
ved
LSI
RDY
F
Bit
Name
Access
Description
Reset
value
[31:24] Reserved
RO Reserved
0
23
CSSC
WO
Clear the clock security system interrupt flag bit (CSSF).
1: Clear the CSSF interrupt flag.
0: No action.
0
[22:21] Reserved
RO Reserved
0
20
PLLRDYC
WO
Clear the PLL-ready interrupt flag bit.
1: Clear the PLLRDYF interrupt flag.
0: No action.
0
19
HSERDYC
WO
Clear the HSE oscillator ready interrupt flag bit.
1: Clear the HSERDYF interrupt flag.
0: No action.
0
18
HSIRDYC
WO
Clear the HSI oscillator ready interrupt flag bit.
1: Clear the HSIRDYF interrupt flag.
0: No action.
0
17
Reserved
RO Reserved
0
16
LSIRDYC
WO
Clear the LSI oscillator ready interrupt flag bit.
1: Clear the LSIRDYF interrupt flag.
0