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#include "STM32F0xx.h"
#include "common.h"
/**
* Initialize the HSI clock source and reset the PLL configuration. This
* function is called by the startup_common.s file, just before calling the
* main() function.
*
* You can adapt this function to fit your needs, however, do not change its
* name! It is called in the startup code.
*/
void SystemInit (void) {
// Set HSION bit
RCC->CR |= (uint32_t)0x00000001U;
#if defined (STM32F051x8) || \
defined (STM32F058x8)
// Reset SW[1:0], HPRE[3:0], PPRE[2:0], ADCPRE and MCOSEL[2:0] bits
RCC->CFGR &= (uint32_t)0xF8FFB80CU;
#else
// Reset SW[1:0], HPRE[3:0], PPRE[2:0], ADCPRE, MCOSEL[2:0], MCOPRE[2:0] and PLLNODIV bits
RCC->CFGR &= (uint32_t)0x08FFB80CU;
#endif
// Reset HSEON, CSSON and PLLON bits
RCC->CR &= (uint32_t)0xFEF6FFFFU;
// Reset HSEBYP bit
RCC->CR &= (uint32_t)0xFFFBFFFFU;
// Reset PLLSRC, PLLXTPRE and PLLMUL[3:0] bits
RCC->CFGR &= (uint32_t)0xFFC0FFFFU;
// Reset PREDIV[3:0] bits
RCC->CFGR2 &= (uint32_t)0xFFFFFFF0U;
#if defined (STM32F072xB) || \
defined (STM32F078xx)
// Reset USART2SW[1:0], USART1SW[1:0], I2C1SW, CECSW, USBSW and ADCSW bits
RCC->CFGR3 &= (uint32_t)0xFFFCFE2CU;
#elif defined (STM32F071xB)
// Reset USART2SW[1:0], USART1SW[1:0], I2C1SW, CECSW and ADCSW bits
RCC->CFGR3 &= (uint32_t)0xFFFFCEACU;
#elif defined (STM32F091xC) || \
defined (STM32F098xx)
// Reset USART3SW[1:0], USART2SW[1:0], USART1SW[1:0], I2C1SW, CECSW and ADCSW bits
RCC->CFGR3 &= (uint32_t)0xFFF0FEACU;
#elif defined (STM32F030x6) || \
defined (STM32F030x8) || \
defined (STM32F031x6) || \
defined (STM32F038xx) || \
defined (STM32F030xC)
// Reset USART1SW[1:0], I2C1SW and ADCSW bits
RCC->CFGR3 &= (uint32_t)0xFFFFFEECU;
#elif defined (STM32F051x8) || \
defined (STM32F058xx)
// Reset USART1SW[1:0], I2C1SW, CECSW and ADCSW bits
RCC->CFGR3 &= (uint32_t)0xFFFFFEACU;
#elif defined (STM32F042x6) || \
defined (STM32F048xx)
// Reset USART1SW[1:0], I2C1SW, CECSW, USBSW and ADCSW bits
RCC->CFGR3 &= (uint32_t)0xFFFFFE2CU;
#elif defined (STM32F070x6) || \
defined (STM32F070xB)
// Reset USART1SW[1:0], I2C1SW, USBSW and ADCSW bits
RCC->CFGR3 &= (uint32_t)0xFFFFFE6CU;
// Set default USB clock to PLLCLK, since there is no HSI48
RCC->CFGR3 |= (uint32_t)0x00000080U;
#else
#warning "No target selected"
#endif
// Reset HSI14 bit
RCC->CR2 &= (uint32_t)0xFFFFFFFEU;
// Disable all interrupts
RCC->CIR = 0x00000000U;
}
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