Peripheral Clocks Configuration Functions - ST STM32F31xx User Manual

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Decreasing the CPU frequency
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RCC_SYSCLKConfig()
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RCC_GetSYSCLKSource()
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RCC_HCLKConfig()
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RCC_PCLK1Config()
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RCC_PCLK2Config()
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RCC_GetClocksFreq()
18.2.4

Peripheral clocks configuration functions

This section provide functions allowing to configure the Peripheral clocks.
1. The RTC clock which is derived from the LSE, LSI or HSE_Div32 (HSE divided by
32).
2. After restart from Reset or wakeup from STANDBY, all peripherals are off except
internal SRAM, Flash and SWD. Before to start using a peripheral you have to enable
its interface clock. You can do this using RCC_AHBPeriphClockCmd(),
RCC_APB2PeriphClockCmd() and RCC_APB1PeriphClockCmd() functions.
3. To reset the peripherals configuration (to the default state after device reset) you can
use RCC_AHBPeriphResetCmd(), RCC_APB2PeriphResetCmd() and
RCC_APB1PeriphResetCmd() functions.
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RCC_ADCCLKConfig()
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RCC_I2CCLKConfig()
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RCC_TIMCLKConfig()
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RCC_USARTCLKConfig()
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RCC_USBCLKConfig()
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RCC_RTCCLKConfig()
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RCC_I2SCLKConfig()
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RCC_RTCCLKCmd()
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RCC_BackupResetCmd()
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RCC_AHBPeriphClockCmd()
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RCC_APB2PeriphClockCmd()
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RCC_APB1PeriphClockCmd()
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RCC_AHBPeriphResetCmd()
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RCC_APB2PeriphResetCmd()
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RCC_APB1PeriphResetCmd()
Check that the new number of WS is taken into account by reading FLASH_ACR
Modify the CPU clock source, using "RCC_SYSCLKConfig()" function
If needed, modify the CPU clock prescaler by using "RCC_HCLKConfig()"
function
Check that the new CPU clock source is taken into account by reading the clock
source status, using "RCC_GetSYSCLKSource()" function
Modify the CPU clock source, using "RCC_SYSCLKConfig()" function
If needed, modify the CPU clock prescaler by using "RCC_HCLKConfig()"
function
Check that the new CPU clock source is taken into account by reading the clock
source status, using "RCC_GetSYSCLKSource()" function
Program the new number of WS, using "FLASH_SetLatency()" function
Check that the new number of WS is taken into account by reading FLASH_ACR
Disable the Flash Prefetch buffer using "FLASH_PrefetchBufferCmd(DISABLE)"
function
Check that Flash Prefetch buffer deactivation is taken into account by reading
FLASH_ACR using the FLASH_GetPrefetchBufferStatus() function.
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Reset and clock control (RCC)
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