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GD32F403xx User Manual
88
111: (CK_AHB / 16) selected
10:8
APB1PSC[2:0]
APB1 prescaler selection
Set and reset by software to control the APB1 clock division ratio.
Note
: The CK_APB1 output frequency must not exceed
84 MHz.
0xx: CK_AHB selected
100: (CK_AHB / 2) selected
101: (CK_AHB / 4) selected
110: (CK_AHB / 8) selected
111: (CK_AHB / 16) selected
7:4
AHBPSC[3:0]
AHB prescaler selection
Set and reset by software to control the AHB clock division ratio
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
Содержание GD32F403 Series
Страница 1: ...GigaDevice Semiconductor Inc GD32F403xx Arm Cortex M4 32 bit MCU User Manual Revision 2 6 Jul 2022 ...
Страница 177: ...GD32F403xx UserManual 177 Peripheral Channel 0 Channel 1 Channel 2 Channel 3 Channel 4 SDIO SDIO ...
Страница 217: ...GD32F403xx UserManual 217 ensures that no conversion is in progress ...