/* USER CODE BEGIN Header */
/**
******************************************************************************
* @file Examples_LL/RCC/RCC_UseHSEasSystemClock/Src/main.c
* @author MCD Application Team
* @brief This example describes how to use the RCC LL API how to start the HSE
* and use it as system clock.
******************************************************************************
* @attention
*
* Copyright (c) 2020 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.
*
******************************************************************************
*/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
/* USER CODE END Includes */
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
__IO uint8_t ubReadyState = 0;
/* USER CODE END PTD */
/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
#if (USE_TIMEOUT == 1)
#define TIMEOUT_VALUE 1000 /* Time-out set to 1 sec */
#endif /* USE_TIMEOUT */
/* USER CODE END PD */
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
/* USER CODE END PM */
/* Private variables ---------------------------------------------------------*/
/* USER CODE BEGIN PV */
/* USER CODE END PV */
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
/* USER CODE BEGIN PFP */
void StartHSE(void);
uint32_t RCC_WaitForHSEReady(void);
void LED_On(void);
void LED_Blinking(uint32_t Period);
/* USER CODE END PFP */
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
/* USER CODE END 0 */
/**
* @brief The application entry point.
* @retval int
*/
int main(void)
{
/* USER CODE BEGIN 1 */
register uint32_t frequency = 0;
/* USER CODE END 1 */
/* MCU Configuration--------------------------------------------------------*/
/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
/* System interrupt init*/
NVIC_SetPriorityGrouping(NVIC_PRIORITYGROUP_4);
/* USER CODE BEGIN Init */
/* USER CODE END Init */
/* Configure the system clock */
SystemClock_Config();
/* USER CODE BEGIN SysInit */
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_GPIO_Init();
/* USER CODE BEGIN 2 */
/* Configure Systick to 1 ms with the current frequency which should be MSI */
frequency = __LL_RCC_CALC_MSI_FREQ(LL_RCC_MSI_IsEnabledRangeSelect(), \
(LL_RCC_MSI_IsEnabledRangeSelect() ? \
LL_RCC_MSI_GetRange() : \
LL_RCC_MSI_GetRangeAfterStandby()));
LL_Init1msTick(frequency);
/* Start HSE */
StartHSE();
if (RCC_WaitForHSEReady() == RCC_ERROR_NONE)
{
/* Turn-on LED2 to indicate that HSE is ready */
LED_On();
ubReadyState = 1 ;
}
else
{
/* Problem to switch to HSE, blink LED2 */
LED_Blinking(LED_BLINK_ERROR);
ubReadyState = 0xE ;
}
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}
/**
* @brief System Clock Configuration
* @retval None
*/
void SystemClock_Config(void)
{
LL_FLASH_SetLatency(LL_FLASH_LATENCY_2);
while(LL_FLASH_GetLatency() != LL_FLASH_LATENCY_2)
{
}
LL_PWR_SetRegulVoltageScaling(LL_PWR_REGU_VOLTAGE_SCALE1);
LL_RCC_MSI_Enable();
/* Wait till MSI is ready */
while(LL_RCC_MSI_IsReady() != 1)
{
}
LL_RCC_MSI_EnableRangeSelection();
LL_RCC_MSI_SetRange(LL_RCC_MSIRANGE_11);
LL_RCC_MSI_SetCalibTrimming(0);
LL_RCC_SetSysClkSource(LL_RCC_SYS_CLKSOURCE_MSI);
/* Wait till System clock is ready */
while(LL_RCC_GetSysClkSource() != LL_RCC_SYS_CLKSOURCE_STATUS_MSI)
{
}
LL_RCC_SetAHBPrescaler(LL_RCC_SYSCLK_DIV_1);
LL_RCC_SetAHB3Prescaler(LL_RCC_SYSCLK_DIV_1);
LL_RCC_SetAPB1Prescaler(LL_RCC_APB1_DIV_1);
LL_RCC_SetAPB2Prescaler(LL_RCC_APB2_DIV_1);
LL_Init1msTick(48000000);
/* Update CMSIS variable (which can be updated also through SystemCoreClockUpdate function) */
LL_SetSystemCoreClock(48000000);
}
/**
* @brief GPIO Initialization Function
* @param None
* @retval None
*/
static void MX_GPIO_Init(void)
{
LL_GPIO_InitTypeDef GPIO_InitStruct = {0};
/* GPIO Ports Clock Enable */
LL_AHB2_GRP1_EnableClock(LL_AHB2_GRP1_PERIPH_GPIOB);
/**/
LL_GPIO_ResetOutputPin(LED2_GPIO_Port, LED2_Pin);
/**/
GPIO_InitStruct.Pin = LED2_Pin;
GPIO_InitStruct.Mode = LL_GPIO_MODE_OUTPUT;
GPIO_InitStruct.Speed = LL_GPIO_SPEED_FREQ_LOW;
GPIO_InitStruct.OutputType = LL_GPIO_OUTPUT_PUSHPULL;
GPIO_InitStruct.Pull = LL_GPIO_PULL_NO;
LL_GPIO_Init(LED2_GPIO_Port, &GPIO_InitStruct);
}
/* USER CODE BEGIN 4 */
/**
* Brief This function enables the interruption HSE ready,
* and start the HSE as external clock.
* @param None
* Retval None
*/
void StartHSE(void)
{
/* Configure NVIC for RCC */
NVIC_EnableIRQ(RCC_IRQn);
NVIC_SetPriority(RCC_IRQn, 0);
/* Enable interrupt on HSE ready */
/* Enable the CSS
Enable HSE */
/* Note : the clock is switched to HSE in the RCC_IRQHandler ISR */
LL_RCC_EnableIT_HSERDY();
LL_RCC_HSE_EnableCSS();
LL_RCC_HSE_EnableTcxo();
LL_RCC_HSE_Enable();
}
/**
* @brief Wait for HSE ready
* @param None
* @retval RCC_ERROR_NONE if no error
*/
uint32_t RCC_WaitForHSEReady()
{
#if (USE_TIMEOUT == 1)
/* Set timeout to 1 sec */
uint32_t timeout = TIMEOUT_VALUE;
#endif /* USE_TIMEOUT */
/* Check that the condition is met */
while (LL_RCC_GetSysClkSource() != LL_RCC_SYS_CLKSOURCE_STATUS_HSE)
{
#if (USE_TIMEOUT == 1)
/* Check Systick counter flag to decrement the time-out value */
if (LL_SYSTICK_IsActiveCounterFlag())
{
if (--timeout == 0)
{
/* Time-out occurred. Return an error */
return RCC_ERROR_TIMEOUT;
}
}
#endif /* USE_TIMEOUT */
}
return RCC_ERROR_NONE;
}
/**
* @brief Turn-on LED2.
* @param None
* @retval None
*/
void LED_On(void)
{
/* Turn LED2 on */
LL_GPIO_SetOutputPin(LED2_GPIO_Port, LED2_Pin);
}
/**
* @brief Set LED2 to Blinking mode for an infinite loop (toggle period based on value provided as input parameter).
* @param Period : Period of time (in ms) between each toggling of LED
* This parameter can be user defined values. Pre-defined values used in that example are :
* @arg LED_BLINK_FAST : Fast Blinking
* @arg LED_BLINK_SLOW : Slow Blinking
* @arg LED_BLINK_ERROR : Error specific Blinking
* @retval None
*/
void LED_Blinking(uint32_t Period)
{
/* Turn LED2 on */
LL_GPIO_SetOutputPin(LED2_GPIO_Port, LED2_Pin);
/* Toggle IO in an infinite loop */
while (1)
{
/* Error if LED2 is slowly blinking (1 sec. period) */
LL_GPIO_TogglePin(LED2_GPIO_Port, LED2_Pin);
LL_mDelay(Period);
}
}
/******************************************************************************/
/* USER IRQ HANDLER TREATMENT */
/******************************************************************************/
/**
* @brief This function handles the HSE ready detection (called in RCC_IRQHandler)
* @param None
* @retval None
*/
void HSEReady_Callback(void)
{
/* Switch the system clock to HSE */
LL_RCC_SetSysClkSource(LL_RCC_SYS_CLKSOURCE_HSE);
/* 1ms config with HSE 32MHz*/
LL_Init1msTick(HSE_VALUE);
}
/**
* @brief This function handles failure detected on the HSE clock (called in NMI_Handler)
* @param None
* @retval None
*/
void HSEFailureDetection_Callback(void)
{
LED_Blinking(LED_BLINK_ERROR);
}
/* USER CODE END 4 */
/**
* @brief This function is executed in case of error occurrence.
* @retval None
*/
void Error_Handler(void)
{
/* USER CODE BEGIN Error_Handler_Debug */
/* User can add his own implementation to report the HAL error return state */
/* USER CODE END Error_Handler_Debug */
}
#ifdef USE_FULL_ASSERT
/**
* @brief Reports the name of the source file and the source line number
* where the assert_param error has occurred.
* @param file: pointer to the source file name
* @param line: assert_param error line source number
* @retval None
*/
void assert_failed(uint8_t *file, uint32_t line)
{
/* USER CODE BEGIN 6 */
/* User can add his own implementation to report the file name and line number,
ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
/* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */