最近項目需要使用到動态調節方波占空比，通過網上查閱資料，結合晶片手冊，發現STM32G071的TIM1中的PWM可以通過DMA來實作動态修改。
原理就是通過DMA将使用者定義的脈沖占空比數組發送到TIM1_CCRn寄存器，數組的大小決定了脈沖的數量，數組的值決定了每個脈沖的占空比。
話不多說，先上Cube進行最基本的配置（時鐘，定時器，DMA）:
主函數
/* USER CODE BEGIN Header */
/**
******************************************************************************
* @file : main.c
* @brief : Main program body
******************************************************************************
* @attention
*
* <h2><center>© Copyright (c) 2021 STMicroelectronics.
* All rights reserved.</center></h2>
*
* This software component is licensed by ST under BSD 3-Clause license,
* the "License"; You may not use this file except in compliance with the
* License. You may obtain a copy of the License at:
* opensource.org/licenses/BSD-3-Clause
*
******************************************************************************
*/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "dma.h"
#include "tim.h"
#include "gpio.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
/* USER CODE END Includes */
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
/* USER CODE END PTD */
/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* 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);
/* USER CODE BEGIN PFP */
/* USER CODE END PFP */
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
#define NUM 100
uint16_t send_Buf[NUM]={0}; /* 建立一個數組用于測試 */
/* USER CODE END 0 */
/**
* @brief The application entry point.
* @retval int
*/
int main(void)
{
/* USER CODE BEGIN 1 */
for(int i=0;i<NUM;i++)
{
send_Buf[i]=100*(i%5); /* 設定不同的占空比 */
}
/* USER CODE END 1 */
/* MCU Configuration--------------------------------------------------------*/
/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
HAL_Init();
/* 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();
MX_DMA_Init();
MX_TIM1_Init();
/* USER CODE BEGIN 2 */
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
HAL_Delay(200);
HAL_TIM_PWM_Start_DMA(&htim1, TIM_CHANNEL_2,(uint32_t*)send_Buf,NUM);/* 開啟TIM1通道2的DMA傳輸 */
HAL_TIM_PWM_Start_DMA(&htim1, TIM_CHANNEL_3,(uint32_t*)send_Buf,NUM);/* 開啟TIM1通道3的DMA傳輸 */
}
/* USER CODE END 3 */
}
/* 傳輸完一幀資料以後暫停DMA */
void HAL_TIM_PWM_PulseFinishedCallback(TIM_HandleTypeDef *htim)
{
if(htim->Channel==HAL_TIM_ACTIVE_CHANNEL_2)
{
HAL_TIM_PWM_Stop_DMA(htim, TIM_CHANNEL_2);
}else if(htim->Channel==HAL_TIM_ACTIVE_CHANNEL_3)
{
HAL_TIM_PWM_Stop_DMA(htim, TIM_CHANNEL_3);
}
}
/**
* @brief System Clock Configuration
* @retval None
*/
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
RCC_PeriphCLKInitTypeDef PeriphClkInit = {0};
/** Configure the main internal regulator output voltage
*/
HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1);
/** Initializes the RCC Oscillators according to the specified parameters
* in the RCC_OscInitTypeDef structure.
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
RCC_OscInitStruct.HSIState = RCC_HSI_ON;
RCC_OscInitStruct.HSIDiv = RCC_HSI_DIV1;
RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
RCC_OscInitStruct.PLL.PLLM = RCC_PLLM_DIV1;
RCC_OscInitStruct.PLL.PLLN = 8;
RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2;
RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
Error_Handler();
}
/** Initializes the CPU, AHB and APB buses clocks
*/
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
|RCC_CLOCKTYPE_PCLK1;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
{
Error_Handler();
}
/** Initializes the peripherals clocks
*/
PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_TIM1;
PeriphClkInit.Tim1ClockSelection = RCC_TIM1CLKSOURCE_PCLK1;
if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
{
Error_Handler();
}
}
/* USER CODE BEGIN 4 */
/* 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 */
__disable_irq();
while (1)
{
}
/* 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 */
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
定時器配置
/**
******************************************************************************
* @file tim.c
* @brief This file provides code for the configuration
* of the TIM instances.
******************************************************************************
* @attention
*
* <h2><center>© Copyright (c) 2021 STMicroelectronics.
* All rights reserved.</center></h2>
*
* This software component is licensed by ST under BSD 3-Clause license,
* the "License"; You may not use this file except in compliance with the
* License. You may obtain a copy of the License at:
* opensource.org/licenses/BSD-3-Clause
*
******************************************************************************
*/
/* Includes ------------------------------------------------------------------*/
#include "tim.h"
/* USER CODE BEGIN 0 */
/* USER CODE END 0 */
TIM_HandleTypeDef htim1;
DMA_HandleTypeDef hdma_tim1_ch2;
DMA_HandleTypeDef hdma_tim1_ch3;
/* TIM1 init function */
void MX_TIM1_Init(void)
{
TIM_ClockConfigTypeDef sClockSourceConfig = {0};
TIM_MasterConfigTypeDef sMasterConfig = {0};
TIM_OC_InitTypeDef sConfigOC = {0};
TIM_BreakDeadTimeConfigTypeDef sBreakDeadTimeConfig = {0};
htim1.Instance = TIM1;
htim1.Init.Prescaler = 63;
htim1.Init.CounterMode = TIM_COUNTERMODE_UP;
htim1.Init.Period = 1000;
htim1.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
htim1.Init.RepetitionCounter = 0;
htim1.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
if (HAL_TIM_Base_Init(&htim1) != HAL_OK)
{
Error_Handler();
}
sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
if (HAL_TIM_ConfigClockSource(&htim1, &sClockSourceConfig) != HAL_OK)
{
Error_Handler();
}
if (HAL_TIM_PWM_Init(&htim1) != HAL_OK)
{
Error_Handler();
}
sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
sMasterConfig.MasterOutputTrigger2 = TIM_TRGO2_RESET;
sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
if (HAL_TIMEx_MasterConfigSynchronization(&htim1, &sMasterConfig) != HAL_OK)
{
Error_Handler();
}
sConfigOC.OCMode = TIM_OCMODE_PWM2;/* PWM2模式下
a)如果設定TIM_OCPolarity_High:
TIMx_CNT<TIMx_CCR輸出為低電平
TIMx_CNT>TIMx_CCR輸出為高電平
b)如果設定TIM_OCPolarity_Low:
TIMx_CNT<TIMx_CCR輸出為高電平
TIMx_CNT>TIMx_CCR輸出為低電平*/
sConfigOC.Pulse = 0;
sConfigOC.OCPolarity = TIM_OCPOLARITY_LOW;
sConfigOC.OCNPolarity = TIM_OCNPOLARITY_HIGH;
sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
sConfigOC.OCIdleState = TIM_OCIDLESTATE_RESET;
sConfigOC.OCNIdleState = TIM_OCNIDLESTATE_RESET;
if (HAL_TIM_PWM_ConfigChannel(&htim1, &sConfigOC, TIM_CHANNEL_2) != HAL_OK)
{
Error_Handler();
}
sConfigOC.OCMode = TIM_OCMODE_PWM1;/* PWM1模式下
a)如果設定TIM_OCPolarity_High:
TIMx_CNT<TIMx_CCR輸出為高電平
TIMx_CNT>TIMx_CCR輸出為低電平
b)如果設定TIM_OCPolarity_Low:
TIMx_CNT<TIMx_CCR輸出為低電平
TIMx_CNT>TIMx_CCR輸出為高電平*/
sConfigOC.OCIdleState = TIM_OCIDLESTATE_SET;
if (HAL_TIM_PWM_ConfigChannel(&htim1, &sConfigOC, TIM_CHANNEL_3) != HAL_OK)
{
Error_Handler();
}
sBreakDeadTimeConfig.OffStateRunMode = TIM_OSSR_DISABLE;
sBreakDeadTimeConfig.OffStateIDLEMode = TIM_OSSI_DISABLE;
sBreakDeadTimeConfig.LockLevel = TIM_LOCKLEVEL_OFF;
sBreakDeadTimeConfig.DeadTime = 0;
sBreakDeadTimeConfig.BreakState = TIM_BREAK_DISABLE;
sBreakDeadTimeConfig.BreakPolarity = TIM_BREAKPOLARITY_HIGH;
sBreakDeadTimeConfig.BreakFilter = 0;
sBreakDeadTimeConfig.BreakAFMode = TIM_BREAK_AFMODE_INPUT;
sBreakDeadTimeConfig.Break2State = TIM_BREAK2_DISABLE;
sBreakDeadTimeConfig.Break2Polarity = TIM_BREAK2POLARITY_HIGH;
sBreakDeadTimeConfig.Break2Filter = 0;
sBreakDeadTimeConfig.Break2AFMode = TIM_BREAK_AFMODE_INPUT;
sBreakDeadTimeConfig.AutomaticOutput = TIM_AUTOMATICOUTPUT_DISABLE;
if (HAL_TIMEx_ConfigBreakDeadTime(&htim1, &sBreakDeadTimeConfig) != HAL_OK)
{
Error_Handler();
}
HAL_TIM_MspPostInit(&htim1);
}
void HAL_TIM_Base_MspInit(TIM_HandleTypeDef* tim_baseHandle)
{
if(tim_baseHandle->Instance==TIM1)
{
/* USER CODE BEGIN TIM1_MspInit 0 */
/* USER CODE END TIM1_MspInit 0 */
/* TIM1 clock enable */
__HAL_RCC_TIM1_CLK_ENABLE();
/* TIM1 DMA Init */
/* TIM1_CH2 Init */
hdma_tim1_ch2.Instance = DMA1_Channel1;
hdma_tim1_ch2.Init.Request = DMA_REQUEST_TIM1_CH2;
hdma_tim1_ch2.Init.Direction = DMA_MEMORY_TO_PERIPH;
hdma_tim1_ch2.Init.PeriphInc = DMA_PINC_DISABLE;
hdma_tim1_ch2.Init.MemInc = DMA_MINC_ENABLE;
hdma_tim1_ch2.Init.PeriphDataAlignment = DMA_PDATAALIGN_HALFWORD;
hdma_tim1_ch2.Init.MemDataAlignment = DMA_MDATAALIGN_HALFWORD;
hdma_tim1_ch2.Init.Mode = DMA_NORMAL;
hdma_tim1_ch2.Init.Priority = DMA_PRIORITY_MEDIUM;
if (HAL_DMA_Init(&hdma_tim1_ch2) != HAL_OK)
{
Error_Handler();
}
__HAL_LINKDMA(tim_baseHandle,hdma[TIM_DMA_ID_CC2],hdma_tim1_ch2);
/* TIM1_CH3 Init */
hdma_tim1_ch3.Instance = DMA1_Channel2;
hdma_tim1_ch3.Init.Request = DMA_REQUEST_TIM1_CH3;
hdma_tim1_ch3.Init.Direction = DMA_MEMORY_TO_PERIPH;
hdma_tim1_ch3.Init.PeriphInc = DMA_PINC_DISABLE;
hdma_tim1_ch3.Init.MemInc = DMA_MINC_ENABLE;
hdma_tim1_ch3.Init.PeriphDataAlignment = DMA_PDATAALIGN_WORD;
hdma_tim1_ch3.Init.MemDataAlignment = DMA_MDATAALIGN_WORD;
hdma_tim1_ch3.Init.Mode = DMA_NORMAL;
hdma_tim1_ch3.Init.Priority = DMA_PRIORITY_MEDIUM;
if (HAL_DMA_Init(&hdma_tim1_ch3) != HAL_OK)
{
Error_Handler();
}
__HAL_LINKDMA(tim_baseHandle,hdma[TIM_DMA_ID_CC3],hdma_tim1_ch3);
/* USER CODE BEGIN TIM1_MspInit 1 */
/* USER CODE END TIM1_MspInit 1 */
}
}
void HAL_TIM_MspPostInit(TIM_HandleTypeDef* timHandle)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
if(timHandle->Instance==TIM1)
{
/* USER CODE BEGIN TIM1_MspPostInit 0 */
/* USER CODE END TIM1_MspPostInit 0 */
__HAL_RCC_GPIOB_CLK_ENABLE();
/**TIM1 GPIO Configuration
PB3 ------> TIM1_CH2
PB6 ------> TIM1_CH3
*/
GPIO_InitStruct.Pin = GPIO_PIN_3|GPIO_PIN_6;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
GPIO_InitStruct.Alternate = GPIO_AF1_TIM1;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
/* USER CODE BEGIN TIM1_MspPostInit 1 */
/* USER CODE END TIM1_MspPostInit 1 */
}
}
void HAL_TIM_Base_MspDeInit(TIM_HandleTypeDef* tim_baseHandle)
{
if(tim_baseHandle->Instance==TIM1)
{
/* USER CODE BEGIN TIM1_MspDeInit 0 */
/* USER CODE END TIM1_MspDeInit 0 */
/* Peripheral clock disable */
__HAL_RCC_TIM1_CLK_DISABLE();
/* TIM1 DMA DeInit */
HAL_DMA_DeInit(tim_baseHandle->hdma[TIM_DMA_ID_CC2]);
HAL_DMA_DeInit(tim_baseHandle->hdma[TIM_DMA_ID_CC3]);
/* USER CODE BEGIN TIM1_MspDeInit 1 */
/* USER CODE END TIM1_MspDeInit 1 */
}
}
/* USER CODE BEGIN 1 */
/* USER CODE END 1 */
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
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