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/**
******************************************************************************
* @file system_stm32l4xx.c
* @author MCD Application Team
* @version V1.1.1
* @date 29-April-2016
* @brief CMSIS Cortex-M4 Device Peripheral Access Layer System Source File
*
* This file provides two functions and one global variable to be called from
* user application:
* - SystemInit(): This function is called at startup just after reset and
* before branch to main program. This call is made inside
* the "startup_stm32l4xx.s" file.
*
* - SystemCoreClock variable: Contains the core clock (HCLK), it can be used
* by the user application to setup the SysTick
* timer or configure other parameters.
*
* - SystemCoreClockUpdate(): Updates the variable SystemCoreClock and must
* be called whenever the core clock is changed
* during program execution.
*
* After each device reset the MSI (4 MHz) is used as system clock source.
* Then SystemInit() function is called, in "startup_stm32l4xx.s" file, to
* configure the system clock before to branch to main program.
*
* This file configures the system clock as follows:
*=============================================================================
* System clock source | 1- PLL_HSE_EXTC | 3- PLL_HSI
* | (external 8 MHz clock) | (internal 16 MHz)
* | 2- PLL_HSE_XTAL | or PLL_MSI
* | (external 8 MHz xtal) | (internal 4 MHz)
*-----------------------------------------------------------------------------
* SYSCLK(MHz) | 48 | 80
*-----------------------------------------------------------------------------
* AHBCLK (MHz) | 48 | 80
*-----------------------------------------------------------------------------
* APB1CLK (MHz) | 48 | 80
*-----------------------------------------------------------------------------
* APB2CLK (MHz) | 48 | 80
*-----------------------------------------------------------------------------
* USB capable (48 MHz precise clock) | YES | NO
*-----------------------------------------------------------------------------
*=============================================================================
******************************************************************************
* @attention
*
* <h2><center>© COPYRIGHT(c) 2016 STMicroelectronics</center></h2>
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. Neither the name of STMicroelectronics nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
******************************************************************************
*/
/** @addtogroup CMSIS
* @{
*/
/** @addtogroup stm32l4xx_system
* @{
*/
/** @addtogroup STM32L4xx_System_Private_Includes
* @{
*/
#include "stm32l4xx.h"
#include "hal_tick.h"
#if !defined (HSE_VALUE)
#define HSE_VALUE ((uint32_t)8000000) /*!< Value of the External oscillator in Hz */
#endif /* HSE_VALUE */
#if !defined (MSI_VALUE)
#define MSI_VALUE ((uint32_t)4000000) /*!< Value of the Internal oscillator in Hz*/
#endif /* MSI_VALUE */
#if !defined (HSI_VALUE)
#define HSI_VALUE ((uint32_t)16000000) /*!< Value of the Internal oscillator in Hz*/
#endif /* HSI_VALUE */
/**
* @}
*/
/** @addtogroup STM32L4xx_System_Private_TypesDefinitions
* @{
*/
/**
* @}
*/
/** @addtogroup STM32L4xx_System_Private_Defines
* @{
*/
/************************* Miscellaneous Configuration ************************/
/*!< Uncomment the following line if you need to relocate your vector Table in
Internal SRAM. */
/* #define VECT_TAB_SRAM */
#define VECT_TAB_OFFSET 0x00 /*!< Vector Table base offset field.
This value must be a multiple of 0x200. */
/******************************************************************************/
/**
* @}
*/
/** @addtogroup STM32L4xx_System_Private_Macros
* @{
*/
// Select the clock sources (default is PLL_MSI) to start with (0=OFF, 1=ON)
#define USE_PLL_HSE_EXTC (1) // Use external clock
#define USE_PLL_HSE_XTAL (0) // Use external xtal
#define USE_PLL_HSI (0) // Use HSI/MSI internal clock (0=MSI, 1=HSI)
#define DEBUG_MCO (0) // Output the MCO on PA8 for debugging (0=OFF, 1=SYSCLK, 2=HSE, 3=HSI, 4=MSI)
/**
* @}
*/
/** @addtogroup STM32L4xx_System_Private_Variables
* @{
*/
/* The SystemCoreClock variable is updated in three ways:
1) by calling CMSIS function SystemCoreClockUpdate()
2) by calling HAL API function HAL_RCC_GetHCLKFreq()
3) each time HAL_RCC_ClockConfig() is called to configure the system clock frequency
Note: If you use this function to configure the system clock; then there
is no need to call the 2 first functions listed above, since SystemCoreClock
variable is updated automatically.
*/
uint32_t SystemCoreClock = 4000000;
const uint8_t AHBPrescTable[16] = {0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 6, 7, 8, 9};
const uint8_t APBPrescTable[8] = {0, 0, 0, 0, 1, 2, 3, 4};
const uint32_t MSIRangeTable[12] = {100000, 200000, 400000, 800000, 1000000, 2000000, \
4000000, 8000000, 16000000, 24000000, 32000000, 48000000};
/**
* @}
*/
/** @addtogroup STM32L4xx_System_Private_FunctionPrototypes
* @{
*/
#if (USE_PLL_HSE_XTAL != 0) || (USE_PLL_HSE_EXTC != 0)
uint8_t SetSysClock_PLL_HSE(uint8_t bypass);
#endif
#if (USE_PLL_HSI != 0)
uint8_t SetSysClock_PLL_HSI(void);
#endif
uint8_t SetSysClock_PLL_MSI(void);
/**
* @}
*/
/** @addtogroup STM32L4xx_System_Private_Functions
* @{
*/
/**
* @brief Setup the microcontroller system.
* @param None
* @retval None
*/
void SystemInit(void)
{
/* FPU settings ------------------------------------------------------------*/
#if (__FPU_PRESENT == 1) && (__FPU_USED == 1)
SCB->CPACR |= ((3UL << 10*2)|(3UL << 11*2)); /* set CP10 and CP11 Full Access */
#endif
/* Reset the RCC clock configuration to the default reset state ------------*/
/* Set MSION bit */
RCC->CR |= RCC_CR_MSION;
/* Reset CFGR register */
RCC->CFGR = 0x00000000;
/* Reset HSEON, CSSON , HSION, and PLLON bits */
RCC->CR &= (uint32_t)0xEAF6FFFF;
/* Reset PLLCFGR register */
RCC->PLLCFGR = 0x00001000;
/* Reset HSEBYP bit */
RCC->CR &= (uint32_t)0xFFFBFFFF;
/* Disable all interrupts */
RCC->CIER = 0x00000000;
/* Configure the Vector Table location add offset address ------------------*/
#ifdef VECT_TAB_SRAM
SCB->VTOR = SRAM_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal SRAM */
#else
SCB->VTOR = FLASH_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal FLASH */
#endif
/* Configure the Cube driver */
SystemCoreClock = MSI_VALUE; // At this stage the MSI is used as system clock
HAL_Init();
/* Configure the System clock source, PLL Multiplier and Divider factors,
AHB/APBx prescalers and Flash settings */
SetSysClock();
/* Reset the timer to avoid issues after the RAM initialization */
TIM_MST_RESET_ON;
TIM_MST_RESET_OFF;
}
/**
* @brief Update SystemCoreClock variable according to Clock Register Values.
* The SystemCoreClock variable contains the core clock (HCLK), it can
* be used by the user application to setup the SysTick timer or configure
* other parameters.
*
* @note Each time the core clock (HCLK) changes, this function must be called
* to update SystemCoreClock variable value. Otherwise, any configuration
* based on this variable will be incorrect.
*
* @note - The system frequency computed by this function is not the real
* frequency in the chip. It is calculated based on the predefined
* constant and the selected clock source:
*
* - If SYSCLK source is MSI, SystemCoreClock will contain the MSI_VALUE(*)
*
* - If SYSCLK source is HSI, SystemCoreClock will contain the HSI_VALUE(**)
*
* - If SYSCLK source is HSE, SystemCoreClock will contain the HSE_VALUE(***)
*
* - If SYSCLK source is PLL, SystemCoreClock will contain the HSE_VALUE(***)
* or HSI_VALUE(*) or MSI_VALUE(*) multiplied/divided by the PLL factors.
*
* (*) MSI_VALUE is a constant defined in stm32l4xx_hal.h file (default value
* 4 MHz) but the real value may vary depending on the variations
* in voltage and temperature.
*
* (**) HSI_VALUE is a constant defined in stm32l4xx_hal.h file (default value
* 16 MHz) but the real value may vary depending on the variations
* in voltage and temperature.
*
* (***) HSE_VALUE is a constant defined in stm32l4xx_hal.h file (default value
* 8 MHz), user has to ensure that HSE_VALUE is same as the real
* frequency of the crystal used. Otherwise, this function may
* have wrong result.
*
* - The result of this function could be not correct when using fractional
* value for HSE crystal.
*
* @param None
* @retval None
*/
void SystemCoreClockUpdate(void)
{
uint32_t tmp = 0, msirange = 0, pllvco = 0, pllr = 2, pllsource = 0, pllm = 2;
/* Get MSI Range frequency--------------------------------------------------*/
if((RCC->CR & RCC_CR_MSIRGSEL) == RESET)
{ /* MSISRANGE from RCC_CSR applies */
msirange = (RCC->CSR & RCC_CSR_MSISRANGE) >> 8;
}
else
{ /* MSIRANGE from RCC_CR applies */
msirange = (RCC->CR & RCC_CR_MSIRANGE) >> 4;
}
/*MSI frequency range in HZ*/
msirange = MSIRangeTable[msirange];
/* Get SYSCLK source -------------------------------------------------------*/
switch (RCC->CFGR & RCC_CFGR_SWS)
{
case 0x00: /* MSI used as system clock source */
SystemCoreClock = msirange;
break;
case 0x04: /* HSI used as system clock source */
SystemCoreClock = HSI_VALUE;
break;
case 0x08: /* HSE used as system clock source */
SystemCoreClock = HSE_VALUE;
break;
case 0x0C: /* PLL used as system clock source */
/* PLL_VCO = (HSE_VALUE or HSI_VALUE or MSI_VALUE/ PLLM) * PLLN
SYSCLK = PLL_VCO / PLLR
*/
pllsource = (RCC->PLLCFGR & RCC_PLLCFGR_PLLSRC);
pllm = ((RCC->PLLCFGR & RCC_PLLCFGR_PLLM) >> 4) + 1 ;
switch (pllsource)
{
case 0x02: /* HSI used as PLL clock source */
pllvco = (HSI_VALUE / pllm);
break;
case 0x03: /* HSE used as PLL clock source */
pllvco = (HSE_VALUE / pllm);
break;
default: /* MSI used as PLL clock source */
pllvco = (msirange / pllm);
break;
}
pllvco = pllvco * ((RCC->PLLCFGR & RCC_PLLCFGR_PLLN) >> 8);
pllr = (((RCC->PLLCFGR & RCC_PLLCFGR_PLLR) >> 25) + 1) * 2;
SystemCoreClock = pllvco/pllr;
break;
default:
SystemCoreClock = msirange;
break;
}
/* Compute HCLK clock frequency --------------------------------------------*/
/* Get HCLK prescaler */
tmp = AHBPrescTable[((RCC->CFGR & RCC_CFGR_HPRE) >> 4)];
/* HCLK clock frequency */
SystemCoreClock >>= tmp;
}
/**
* @brief Configures the System clock source, PLL Multiplier and Divider factors,
* AHB/APBx prescalers and Flash settings
* @note This function should be called only once the RCC clock configuration
* is reset to the default reset state (done in SystemInit() function).
* @param None
* @retval None
*/
void SetSysClock(void)
{
/* 1- Try to start with HSE and external clock */
#if USE_PLL_HSE_EXTC != 0
if (SetSysClock_PLL_HSE(1) == 0)
#endif
{
/* 2- If fail try to start with HSE and external xtal */
#if USE_PLL_HSE_XTAL != 0
if (SetSysClock_PLL_HSE(0) == 0)
#endif
{
/* 3- If fail start with HSI or MSI clock */
#if (USE_PLL_HSI != 0)
if (SetSysClock_PLL_HSI() == 0)
#else
if (SetSysClock_PLL_MSI() == 0)
#endif
{
while(1)
{
// [TODO] Put something here to tell the user that a problem occured...
}
}
}
}
// Output clock on MCO1 pin(PA8) for debugging purpose
#if DEBUG_MCO == 1
HAL_RCC_MCOConfig(RCC_MCO1, RCC_MCO1SOURCE_SYSCLK, RCC_MCODIV_1);
#endif
}
#if (USE_PLL_HSE_XTAL != 0) || (USE_PLL_HSE_EXTC != 0)
/******************************************************************************/
/* PLL (clocked by HSE) used as System clock source */
/******************************************************************************/
uint8_t SetSysClock_PLL_HSE(uint8_t bypass)
{
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
// Used to gain time after DeepSleep in case HSI is used
if (__HAL_RCC_GET_FLAG(RCC_FLAG_HSIRDY) != RESET)
{
return 0;
}
// Select MSI as system clock source to allow modification of the PLL configuration
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_SYSCLK;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_MSI;
HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0);
// Enable HSE oscillator and activate PLL with HSE as source
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE | RCC_OSCILLATORTYPE_HSI;
if (bypass == 0)
{
RCC_OscInitStruct.HSEState = RCC_HSE_ON; // External 8 MHz xtal on OSC_IN/OSC_OUT
}
else
{
RCC_OscInitStruct.HSEState = RCC_HSE_BYPASS; // External 8 MHz clock on OSC_IN
}
RCC_OscInitStruct.HSIState = RCC_HSI_OFF;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE; // 8 MHz
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
// Non-USB configuration : sysclock = 80MHz
//RCC_OscInitStruct.PLL.PLLM = 1; // VCO input clock = 8 MHz (8 MHz / 1)
//RCC_OscInitStruct.PLL.PLLN = 20; // VCO output clock = 160 MHz (8 MHz * 20)
//RCC_OscInitStruct.PLL.PLLP = 7; // PLLSAI3 clock = 22 MHz (160 MHz / 7)
//RCC_OscInitStruct.PLL.PLLQ = 4; // USB clock (PLL48M1) = 40 MHz (160 MHz / 4) --> Not good for USB
//RCC_OscInitStruct.PLL.PLLR = 2; // PLL clock = 80 MHz (160 MHz / 2)
// USB configuration : sysclock = 48 MHz
RCC_OscInitStruct.PLL.PLLM = 1; // VCO input clock = 8 MHz (8 MHz / 1)
RCC_OscInitStruct.PLL.PLLN = 24; // VCO output clock = 192 MHz (8 MHz * 24)
RCC_OscInitStruct.PLL.PLLP = 7; // PLLSAI3 clock = 27.4 MHz (192 MHz / 7)
RCC_OscInitStruct.PLL.PLLQ = 4; // USB clock (PLL48M1) = 48 MHz (192 MHz / 4) --> OK for USB
RCC_OscInitStruct.PLL.PLLR = 4; // PLL clock = 48 MHz (192 MHz / 4)
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
return 0; // FAIL
}
// Select PLL clock as system clock source and configure the HCLK, PCLK1 and PCLK2 clocks dividers
RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK; // 80 MHz or 48 MHz
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1; // 80 MHz or 48 MHz
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1; // 80 MHz or 48 MHz
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1; // 80 MHz or 48 MHz
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_4) != HAL_OK)
{
return 0; // FAIL
}
// Disable MSI Oscillator
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_MSI;
RCC_OscInitStruct.MSIState = RCC_MSI_OFF;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE; // No PLL update
HAL_RCC_OscConfig(&RCC_OscInitStruct);
// Output clock on MCO1 pin(PA8) for debugging purpose
#if DEBUG_MCO == 2
if (bypass == 0)
HAL_RCC_MCOConfig(RCC_MCO1, RCC_MCO1SOURCE_HSE, RCC_MCODIV_2); // 4 MHz
else
HAL_RCC_MCOConfig(RCC_MCO1, RCC_MCO1SOURCE_HSE, RCC_MCODIV_1); // 8 MHz
#endif
return 1; // OK
}
#endif
#if (USE_PLL_HSI != 0)
/******************************************************************************/
/* PLL (clocked by HSI) used as System clock source */
/******************************************************************************/
uint8_t SetSysClock_PLL_HSI(void)
{
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
// Select MSI as system clock source to allow modification of the PLL configuration
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_SYSCLK;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_MSI;
HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0);
// Enable HSI oscillator and activate PLL with HSI as source
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI | RCC_OSCILLATORTYPE_HSE;
RCC_OscInitStruct.HSEState = RCC_HSE_OFF;
RCC_OscInitStruct.HSIState = RCC_HSI_ON;
RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI; // 16 MHz
RCC_OscInitStruct.PLL.PLLM = 2; // VCO input clock = 8 MHz (16 MHz / 2)
RCC_OscInitStruct.PLL.PLLN = 20; // VCO output clock = 160 MHz (8 MHz * 20)
RCC_OscInitStruct.PLL.PLLP = 7; // PLLSAI3 clock = 22 MHz (160 MHz / 7)
RCC_OscInitStruct.PLL.PLLQ = 4; // USB clock (PLL48M1) = 40 MHz (160 MHz / 4) --> Not good for USB
RCC_OscInitStruct.PLL.PLLR = 2; // PLL clock = 80 MHz (160 MHz / 2)
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
return 0; // FAIL
}
// Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2 clocks dividers
RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK; // 80 MHz
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1; // 80 MHz
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1; // 80 MHz
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1; // 80 MHz
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_4) != HAL_OK)
{
return 0; // FAIL
}
// Disable MSI Oscillator
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_MSI;
RCC_OscInitStruct.MSIState = RCC_MSI_OFF;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE; // No PLL update
HAL_RCC_OscConfig(&RCC_OscInitStruct);
// Output clock on MCO1 pin(PA8) for debugging purpose
#if DEBUG_MCO == 3
HAL_RCC_MCOConfig(RCC_MCO1, RCC_MCO1SOURCE_HSI, RCC_MCODIV_1); // 16 MHz
#endif
return 1; // OK
}
#endif
/******************************************************************************/
/* PLL (clocked by MSI) used as System clock source */
/******************************************************************************/
uint8_t SetSysClock_PLL_MSI(void)
{
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
// Enable LSE Oscillator to automatically calibrate the MSI clock
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSE;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE; // No PLL update
RCC_OscInitStruct.LSEState = RCC_LSE_ON; // External 32.768 kHz clock on OSC_IN/OSC_OUT
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) == HAL_OK) {
RCC->CR |= RCC_CR_MSIPLLEN; // Enable MSI PLL-mode
}
// Enable MSI oscillator and activate PLL with MSI as source
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_MSI | RCC_OSCILLATORTYPE_HSI | RCC_OSCILLATORTYPE_HSE;
RCC_OscInitStruct.MSIState = RCC_MSI_ON;
RCC_OscInitStruct.HSEState = RCC_HSE_OFF;
RCC_OscInitStruct.HSIState = RCC_HSI_OFF;
RCC_OscInitStruct.MSIClockRange = RCC_MSIRANGE_6;
RCC_OscInitStruct.MSICalibrationValue = RCC_MSICALIBRATION_DEFAULT;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_MSI; // 4 MHz
RCC_OscInitStruct.PLL.PLLM = 1; // VCO input clock = 4 MHz (4 MHz / 1)
RCC_OscInitStruct.PLL.PLLN = 40; // VCO output clock = 160 MHz (4 MHz * 40)
RCC_OscInitStruct.PLL.PLLP = 7; // PLLSAI3 clock = 22.86 MHz (160 MHz / 7)
RCC_OscInitStruct.PLL.PLLQ = 4; // USB clock (PLL48M1) = 40 MHz (160 MHz / 4) --> Not good for USB
RCC_OscInitStruct.PLL.PLLR = 2; // PLL clock = 80 MHz (160 MHz / 2)
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
return 0; // FAIL
}
// Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2 clocks dividers
RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK; // 80 MHz
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1; // 80 MHz
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1; // 80 MHz
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1; // 80 MHz
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_4) != HAL_OK)
{
return 0; // FAIL
}
// Output clock on MCO1 pin(PA8) for debugging purpose
#if DEBUG_MCO == 4
HAL_RCC_MCOConfig(RCC_MCO1, RCC_MCO1SOURCE_MSI, RCC_MCODIV_2); // 2 MHz
#endif
return 1; // OK
}
/**
* @}
*/
/**
* @}
*/
/**
* @}
*/
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/