Initial commit
This commit is contained in:
259
Core/Src/system_stm32f7xx.c
Normal file
259
Core/Src/system_stm32f7xx.c
Normal file
@@ -0,0 +1,259 @@
|
||||
/**
|
||||
******************************************************************************
|
||||
* @file system_stm32f7xx.c
|
||||
* @author MCD Application Team
|
||||
* @brief CMSIS Cortex-M7 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_stm32f7xx.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.
|
||||
*
|
||||
*
|
||||
******************************************************************************
|
||||
* @attention
|
||||
*
|
||||
* Copyright (c) 2016 STMicroelectronics.
|
||||
* All rights reserved.
|
||||
*
|
||||
* This software is licensed under terms that can be found in the LICENSE file
|
||||
* in the root directory of this software component.
|
||||
* If no LICENSE file comes with this software, it is provided AS-IS.
|
||||
*
|
||||
******************************************************************************
|
||||
*/
|
||||
|
||||
/** @addtogroup CMSIS
|
||||
* @{
|
||||
*/
|
||||
|
||||
/** @addtogroup stm32f7xx_system
|
||||
* @{
|
||||
*/
|
||||
|
||||
/** @addtogroup STM32F7xx_System_Private_Includes
|
||||
* @{
|
||||
*/
|
||||
|
||||
#include "stm32f7xx.h"
|
||||
|
||||
#if !defined (HSE_VALUE)
|
||||
#define HSE_VALUE ((uint32_t)25000000) /*!< Default value of the External oscillator in Hz */
|
||||
#endif /* HSE_VALUE */
|
||||
|
||||
#if !defined (HSI_VALUE)
|
||||
#define HSI_VALUE ((uint32_t)16000000) /*!< Value of the Internal oscillator in Hz*/
|
||||
#endif /* HSI_VALUE */
|
||||
|
||||
/**
|
||||
* @}
|
||||
*/
|
||||
|
||||
/** @addtogroup STM32F7xx_System_Private_TypesDefinitions
|
||||
* @{
|
||||
*/
|
||||
|
||||
/**
|
||||
* @}
|
||||
*/
|
||||
|
||||
/** @addtogroup STM32F7xx_System_Private_Defines
|
||||
* @{
|
||||
*/
|
||||
|
||||
/************************* Miscellaneous Configuration ************************/
|
||||
|
||||
/* Note: Following vector table addresses must be defined in line with linker
|
||||
configuration. */
|
||||
/*!< Uncomment the following line if you need to relocate the vector table
|
||||
anywhere in Flash or Sram, else the vector table is kept at the automatic
|
||||
remap of boot address selected */
|
||||
/* #define USER_VECT_TAB_ADDRESS */
|
||||
|
||||
#if defined(USER_VECT_TAB_ADDRESS)
|
||||
/*!< Uncomment the following line if you need to relocate your vector Table
|
||||
in Sram else user remap will be done in Flash. */
|
||||
/* #define VECT_TAB_SRAM */
|
||||
#if defined(VECT_TAB_SRAM)
|
||||
#define VECT_TAB_BASE_ADDRESS RAMDTCM_BASE /*!< Vector Table base address field.
|
||||
This value must be a multiple of 0x200. */
|
||||
#define VECT_TAB_OFFSET 0x00000000U /*!< Vector Table base offset field.
|
||||
This value must be a multiple of 0x200. */
|
||||
#else
|
||||
#define VECT_TAB_BASE_ADDRESS FLASH_BASE /*!< Vector Table base address field.
|
||||
This value must be a multiple of 0x200. */
|
||||
#define VECT_TAB_OFFSET 0x00000000U /*!< Vector Table base offset field.
|
||||
This value must be a multiple of 0x200. */
|
||||
#endif /* VECT_TAB_SRAM */
|
||||
#endif /* USER_VECT_TAB_ADDRESS */
|
||||
/******************************************************************************/
|
||||
|
||||
/**
|
||||
* @}
|
||||
*/
|
||||
|
||||
/** @addtogroup STM32F7xx_System_Private_Macros
|
||||
* @{
|
||||
*/
|
||||
|
||||
/**
|
||||
* @}
|
||||
*/
|
||||
|
||||
/** @addtogroup STM32F7xx_System_Private_Variables
|
||||
* @{
|
||||
*/
|
||||
|
||||
/* This 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 = 16000000;
|
||||
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};
|
||||
|
||||
/**
|
||||
* @}
|
||||
*/
|
||||
|
||||
/** @addtogroup STM32F7xx_System_Private_FunctionPrototypes
|
||||
* @{
|
||||
*/
|
||||
|
||||
/**
|
||||
* @}
|
||||
*/
|
||||
|
||||
/** @addtogroup STM32F7xx_System_Private_Functions
|
||||
* @{
|
||||
*/
|
||||
|
||||
/**
|
||||
* @brief Setup the microcontroller system
|
||||
* Initialize the Embedded Flash Interface, the PLL and update the
|
||||
* SystemFrequency variable.
|
||||
* @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
|
||||
|
||||
/* Configure the Vector Table location -------------------------------------*/
|
||||
#if defined(USER_VECT_TAB_ADDRESS)
|
||||
SCB->VTOR = VECT_TAB_BASE_ADDRESS | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal SRAM */
|
||||
#endif /* USER_VECT_TAB_ADDRESS */
|
||||
}
|
||||
|
||||
/**
|
||||
* @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 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(*) multiplied/divided by the PLL factors.
|
||||
*
|
||||
* (*) HSI_VALUE is a constant defined in stm32f7xx_hal_conf.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 stm32f7xx_hal_conf.h file (default value
|
||||
* 25 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, pllvco = 0, pllp = 2, pllsource = 0, pllm = 2;
|
||||
|
||||
/* Get SYSCLK source -------------------------------------------------------*/
|
||||
tmp = RCC->CFGR & RCC_CFGR_SWS;
|
||||
|
||||
switch (tmp)
|
||||
{
|
||||
case 0x00: /* HSI used as system clock source */
|
||||
SystemCoreClock = HSI_VALUE;
|
||||
break;
|
||||
case 0x04: /* HSE used as system clock source */
|
||||
SystemCoreClock = HSE_VALUE;
|
||||
break;
|
||||
case 0x08: /* PLL used as system clock source */
|
||||
|
||||
/* PLL_VCO = (HSE_VALUE or HSI_VALUE / PLL_M) * PLL_N
|
||||
SYSCLK = PLL_VCO / PLL_P
|
||||
*/
|
||||
pllsource = (RCC->PLLCFGR & RCC_PLLCFGR_PLLSRC) >> 22;
|
||||
pllm = RCC->PLLCFGR & RCC_PLLCFGR_PLLM;
|
||||
|
||||
if (pllsource != 0)
|
||||
{
|
||||
/* HSE used as PLL clock source */
|
||||
pllvco = (HSE_VALUE / pllm) * ((RCC->PLLCFGR & RCC_PLLCFGR_PLLN) >> 6);
|
||||
}
|
||||
else
|
||||
{
|
||||
/* HSI used as PLL clock source */
|
||||
pllvco = (HSI_VALUE / pllm) * ((RCC->PLLCFGR & RCC_PLLCFGR_PLLN) >> 6);
|
||||
}
|
||||
|
||||
pllp = (((RCC->PLLCFGR & RCC_PLLCFGR_PLLP) >>16) + 1 ) *2;
|
||||
SystemCoreClock = pllvco/pllp;
|
||||
break;
|
||||
default:
|
||||
SystemCoreClock = HSI_VALUE;
|
||||
break;
|
||||
}
|
||||
/* Compute HCLK frequency --------------------------------------------------*/
|
||||
/* Get HCLK prescaler */
|
||||
tmp = AHBPrescTable[((RCC->CFGR & RCC_CFGR_HPRE) >> 4)];
|
||||
/* HCLK frequency */
|
||||
SystemCoreClock >>= tmp;
|
||||
}
|
||||
|
||||
/**
|
||||
* @}
|
||||
*/
|
||||
|
||||
/**
|
||||
* @}
|
||||
*/
|
||||
|
||||
/**
|
||||
* @}
|
||||
*/
|
||||
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
|
||||
Reference in New Issue
Block a user