/**
******************************************************************************
* @file TIM/TIM_TimeBase/Src/main.c
* @author MCD Application Team
* @version V1.5.0
* @date 14-April-2017
* @brief This sample code shows how to use STM32F1xx TIM HAL API to generate
* a time base of one second with the corresponding Interrupt request.
******************************************************************************
* @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.
*
******************************************************************************
*/
/* Includes ------------------------------------------------------------------*/
#include "main.h"
/** @addtogroup STM32F1xx_HAL_Examples
* @{
*/
/** @addtogroup TIM_TimeBase
* @{
*/
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* TIM handle declaration */
TIM_HandleTypeDef TimHandle;
/* Prescaler declaration */
uint32_t uwPrescalerValue = 0;
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void Error_Handler(void);
/* Private functions ---------------------------------------------------------*/
/**
* @brief Main program
* @param None
* @retval None
*/
int main(void)
{
/* STM32F1xx HAL library initialization:
- Configure the Flash prefetch
- Systick timer is configured by default as source of time base, but user
can eventually implement his proper time base source (a general purpose
timer for example or other time source), keeping in mind that Time base
duration should be kept 1ms since PPP_TIMEOUT_VALUEs are defined and
handled in milliseconds basis.
- Set NVIC Group Priority to 4
- Low Level Initialization
*/
HAL_Init();
/* Configure the system clock to 24 MHz */
SystemClock_Config();
/* Configure LED3 & LED4 */
BSP_LED_Init(LED3);
BSP_LED_Init(LED4);
/*##-1- Configure the TIM peripheral #######################################*/
/* -----------------------------------------------------------------------
In this example TIM3 input clock (TIM3CLK) is set to APB1 clock (PCLK1),
since APB1 prescaler is equal to 1.
TIM3CLK = PCLK1
PCLK1 = HCLK
=> TIM3CLK = HCLK = SystemCoreClock
To get TIM3 counter clock at 10 KHz, the Prescaler is computed as following:
Prescaler = (TIM3CLK / TIM3 counter clock) - 1
Prescaler = (SystemCoreClock /10 KHz) - 1
Note:
SystemCoreClock variable holds HCLK frequency and is defined in system_stm32f1xx.c file.
Each time the core clock (HCLK) changes, user had to update SystemCoreClock
variable value. Otherwise, any configuration based on this variable will be incorrect.
This variable is updated in three ways:
1) by calling CMSIS function SystemCoreClockUpdate()
2) by calling HAL API function HAL_RCC_GetSysClockFreq()
3) each time HAL_RCC_ClockConfig() is called to configure the system clock frequency
----------------------------------------------------------------------- */
/* Compute the prescaler value to have TIMx counter clock equal to 10000 Hz */
uwPrescalerValue = (uint32_t)(SystemCoreClock / 10000) - 1;
/* Set TIMx instance */
TimHandle.Instance = TIMx;
/* Initialize TIMx peripheral as follows:
+ Period = 10000 - 1
+ Prescaler = (SystemCoreClock/10000) - 1
+ ClockDivision = 0
+ Counter direction = Up
*/
TimHandle.Init.Period = 10000 - 1;
TimHandle.Init.Prescaler = uwPrescalerValue;
TimHandle.Init.ClockDivision = 0;
TimHandle.Init.CounterMode = TIM_COUNTERMODE_UP;
TimHandle.Init.RepetitionCounter = 0;
TimHandle.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
if (HAL_TIM_Base_Init(&TimHandle) != HAL_OK)
{
/* Initialization Error */
Error_Handler();
}
/*##-2- Start the TIM Base generation in interrupt mode ####################*/
/* Start Channel1 */
if (HAL_TIM_Base_Start_IT(&TimHandle) != HAL_OK)
{
/* Starting Error */
Error_Handler();
}
while (1)
{
}
}
/**
* @brief Period elapsed callback in non blocking mode
* @param htim : TIM handle
* @retval None
*/
void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)
{
BSP_LED_Toggle(LED3);
}
/**
* @brief System Clock Configuration
* The system Clock is configured as follow :
* System Clock source = PLL (HSE)
* SYSCLK(Hz) = 24000000
* HCLK(Hz) = 24000000
* AHB Prescaler = 1
* APB1 Prescaler = 1
* APB2 Prescaler = 1
* HSE Frequency(Hz) = 8000000
* HSE PREDIV1 = 2
* PLLMUL = 6
* Flash Latency(WS) = 0
* @param None
* @retval None
*/
void SystemClock_Config(void)
{
RCC_ClkInitTypeDef clkinitstruct = {0};
RCC_OscInitTypeDef oscinitstruct = {0};
/* Enable HSE Oscillator and activate PLL with HSE as source */
oscinitstruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
oscinitstruct.HSEState = RCC_HSE_ON;
oscinitstruct.HSEPredivValue = RCC_HSE_PREDIV_DIV2;
oscinitstruct.PLL.PLLState = RCC_PLL_ON;
oscinitstruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
oscinitstruct.PLL.PLLMUL = RCC_PLL_MUL6;
if (HAL_RCC_OscConfig(&oscinitstruct)!= HAL_OK)
{
/* Initialization Error */
while(1);
}
/* Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2
clocks dividers */
clkinitstruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
clkinitstruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
clkinitstruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
clkinitstruct.APB2CLKDivider = RCC_HCLK_DIV1;
clkinitstruct.APB1CLKDivider = RCC_HCLK_DIV1;
if (HAL_RCC_ClockConfig(&clkinitstruct, FLASH_LATENCY_0)!= HAL_OK)
{
/* Initialization Error */
while(1);
}
}
/**
* @brief This function is executed in case of error occurrence.
* @param None
* @retval None
*/
static void Error_Handler(void)
{
/* Turn LED4 on */
BSP_LED_On(LED4);
while (1)
{
}
}
#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 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) */
/* Infinite loop */
while (1)
{
}
}
#endif
/**
* @}
*/
/**
* @}
*/
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/ |
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