STM32H7的DMA双缓冲控制IO输出脉冲-编程知识

STM32H7的DMA双缓冲控制IO输出脉冲

keil的sct文件配置
MPU配置
初始化DMA双缓冲
初始化TIM12用处触发DMAMUX的请求发生器

keil的sct文件配置

; *************************************************************
; *** Scatter-Loading Description File generated by uVision ***
; *************************************************************LR_IROM1 0x08000000 0x00200000  {    ; load region size_regionER_IROM1 0x08000000 0x00200000  {  ; load address = execution address*.o (RESET, +First)*(InRoot$$Sections).ANY (+RO)}RW_IRAM1 0x20000000 0x00020000  {  ; RW data - 128KB DTCM.ANY (+RW +ZI)}RW_IRAM2 0x24000000 0x00080000  {  ; RW data - 512KB AXI SRAM*(.RAM_D1) }RW_IRAM3 0x30000000 0x00048000  {  ; RW data - 128KB SRAM1(0x30000000) + 128KB SRAM2(0x3002 0000) + 32KB SRAM3(0x30040000)*(.RAM_D2)}RW_IRAM4 0x38000000 0x00010000  {  ; RW data - 64KB SRAM4(0x38000000)*(.RAM_D3)}
}

MPU配置

/* 配置 SRAM4 的属性为 Write through, read allocate，no write allocate */
MPU_InitStruct.Enable = MPU_REGION_ENABLE;
MPU_InitStruct.BaseAddress = 0x38000000;
MPU_InitStruct.Size = ARM_MPU_REGION_SIZE_64KB;
MPU_InitStruct.AccessPermission = MPU_REGION_FULL_ACCESS;
MPU_InitStruct.IsBufferable = MPU_ACCESS_NOT_BUFFERABLE;
MPU_InitStruct.IsCacheable = MPU_ACCESS_CACHEABLE;
MPU_InitStruct.IsShareable = MPU_ACCESS_NOT_SHAREABLE;
MPU_InitStruct.Number = MPU_REGION_NUMBER2;
MPU_InitStruct.TypeExtField = MPU_TEX_LEVEL0;
MPU_InitStruct.SubRegionDisable = 0x00;
MPU_InitStruct.DisableExec = MPU_INSTRUCTION_ACCESS_ENABLE;
HAL_MPU_ConfigRegion(&MPU_InitStruct);

初始化DMA双缓冲

在这里插入图片描述

/*初始化变量*/
#elif defined ( __CC_ARM )
ALIGN_32BYTES(__attribute__((section (".RAM_D3"))) uint32_t IO_Toggle[8]) ={ 0x00000002U, 0x00020000U, 0x00000002U, 0x00020000U, 0x00000002U, 0x00020000U, 0x00000002U, 0x00020000U, };
ALIGN_32BYTES(__attribute__((section (".RAM_D3"))) uint32_t IO_Toggle1[8]) ={ 0x00000002U, 0x00020000U, 0x00000002U, 0x00020000U, 0x00000002U, 0x00020000U, 0x00000002U, 0x00020000U, };
#endif

void bsp_InitTimDMA(void)
{GPIO_InitTypeDef  GPIO_InitStruct;DMA_HandleTypeDef DMA_Handle = {0};HAL_DMA_MuxRequestGeneratorConfigTypeDef dmamux_ReqGenParams = {0};/*##-1- 配置PB1用于PWM输出 ##################################################*/__HAL_RCC_GPIOB_CLK_ENABLE();GPIO_InitStruct.Pin = GPIO_PIN_1;GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;GPIO_InitStruct.Pull = GPIO_NOPULL;GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);/*##-2- 使能DMA1时钟并配置 ##################################################*/__HAL_RCC_DMA1_CLK_ENABLE();DMA_Handle.Instance                 = DMA1_Stream1;            /* 使用的DMA1 Stream1 */DMA_Handle.Init.Request             = DMA_REQUEST_GENERATOR0;  /* 请求类型采用的DMAMUX请求发生器通道0 */  DMA_Handle.Init.Direction           = DMA_MEMORY_TO_PERIPH;    /* 传输方向是从存储器到外设 */  DMA_Handle.Init.PeriphInc           = DMA_PINC_DISABLE;        /* 外设地址自增禁止 */ DMA_Handle.Init.MemInc              = DMA_MINC_ENABLE;         /* 存储器地址自增使能 */  DMA_Handle.Init.PeriphDataAlignment = DMA_PDATAALIGN_WORD;     /* 外设数据传输位宽选择字，即32bit */     DMA_Handle.Init.MemDataAlignment    = DMA_MDATAALIGN_WORD;     /* 存储器数据传输位宽选择字，即32bit */    DMA_Handle.Init.Mode                = DMA_CIRCULAR;            /* 循环模式 */   DMA_Handle.Init.Priority            = DMA_PRIORITY_LOW;        /* 优先级低 */  DMA_Handle.Init.FIFOMode            = DMA_FIFOMODE_DISABLE;    /* 禁止FIFO*/DMA_Handle.Init.FIFOThreshold       = DMA_FIFO_THRESHOLD_FULL; /* 禁止FIFO此位不起作用，用于设置阀值 */DMA_Handle.Init.MemBurst            = DMA_MBURST_SINGLE;       /* 禁止FIFO此位不起作用，用于存储器突发 */DMA_Handle.Init.PeriphBurst         = DMA_PBURST_SINGLE;       /* 禁止FIFO此位不起作用，用于外设突发 *//* 初始化DMA */if(HAL_DMA_Init(&DMA_Handle) != HAL_OK){Error_Handler(__FILE__, __LINE__);     }/* 开启DMA1 Stream1的中断 */HAL_NVIC_SetPriority(DMA1_Stream1_IRQn, 2, 0);HAL_NVIC_EnableIRQ(DMA1_Stream1_IRQn); /*##-4- 配置DMAMUX ###########################################################*/dmamux_ReqGenParams.SignalID  = HAL_DMAMUX1_REQ_GEN_TIM12_TRGO;         /* 请求触发器选择LPTIM2_OUT */dmamux_ReqGenParams.Polarity  = HAL_DMAMUX_REQ_GEN_RISING;              /* 上升沿触发  */dmamux_ReqGenParams.RequestNumber = 1;                                  /* 触发后，传输进行1次DMA传输 */HAL_DMAEx_ConfigMuxRequestGenerator(&DMA_Handle, &dmamux_ReqGenParams); /* 配置DMAMUX */HAL_DMAEx_EnableMuxRequestGenerator (&DMA_Handle);                      /* 使能DMAMUX请求发生器 */   /*##-4- 启动DMA双缓冲传输 ################################################*//*1、此函数会开启DMA的TC，TE和DME中断2、如果用户配置了回调函数DMA_Handle.XferHalfCpltCallback，那么函数HAL_DMA_Init会开启半传输完成中断。3、如果用户使用了DMAMUX的同步模式，此函数会开启同步溢出中断。4、如果用户使用了DMAMUX的请求发生器，此函数会开始请求发生器溢出中断。*/HAL_DMAEx_MultiBufferStart_IT(&DMA_Handle, (uint32_t)IO_Toggle, (uint32_t)&GPIOB->BSRRL,(uint32_t)IO_Toggle1, 8);/* 用不到的中断可以直接关闭 *///DMA1_Stream1->CR &= ~DMA_IT_DME; //DMA1_Stream1->CR &= ~DMA_IT_TE;//DMAMUX1_RequestGenerator0->RGCR &= ~DMAMUX_RGxCR_OIE;TIM12_Config(0);
}

初始化TIM12用处触发DMAMUX的请求发生器

/*
*********************************************************************************************************
*	函 数 名: TIM12_Config
*	功能说明: 配置TIM12，用于触发DMAMUX的请求发生器
*	形    参: _Mode 
*             0 表示配置为100KHz触发频率,配置为100KHz触发频率，如果DMAMUX配置为单边沿触发，那么输出PWM频
*               率是50KHz，双边沿是100KHz。
*			  1 表示配置为10KHz触发频率，如果DMAMUX配置为单边沿触发，那么输出PWM频率是5KHz，双边沿是10KHz。									  
*	返 回 值: 无
*********************************************************************************************************
*/
void TIM12_Config(uint8_t _Mode)
{TIM_HandleTypeDef  htim ={0};TIM_MasterConfigTypeDef sMasterConfig = {0};TIM_OC_InitTypeDef sConfig = {0};uint32_t Period[2] = {1999, 19999};uint32_t Pulse[2]  = {999, 9999};/* 使能时钟 */  __HAL_RCC_TIM12_CLK_ENABLE();/*-----------------------------------------------------------------------bsp.c 文件中 void SystemClock_Config(void) 函数对时钟的配置如下: System Clock source       = PLL (HSE)SYSCLK(Hz)                = 400000000 (CPU Clock)HCLK(Hz)                  = 200000000 (AXI and AHBs Clock)AHB Prescaler             = 2D1 APB3 Prescaler         = 2 (APB3 Clock  100MHz)D2 APB1 Prescaler         = 2 (APB1 Clock  100MHz)D2 APB2 Prescaler         = 2 (APB2 Clock  100MHz)D3 APB4 Prescaler         = 2 (APB4 Clock  100MHz)因为APB1 prescaler != 1, 所以 APB1上的TIMxCLK = APB1 x 2 = 200MHz;因为APB2 prescaler != 1, 所以 APB2上的TIMxCLK = APB2 x 2 = 200MHz;APB4上面的TIMxCLK没有分频，所以就是100MHz;APB1 定时器有 TIM2, TIM3 ,TIM4, TIM5, TIM6, TIM7, TIM12, TIM13, TIM14，LPTIM1APB2 定时器有 TIM1, TIM8 , TIM15, TIM16，TIM17APB4 定时器有 LPTIM2，LPTIM3，LPTIM4，LPTIM5TIM12CLK = 200MHz/(Period + 1) / (Prescaler + 1)函数bsp_InitTimDMA1中DMAMUX1选择的是单边沿触发，每个时钟可以触发两次。----------------------------------------------------------------------- */  HAL_TIM_Base_DeInit(&htim);htim.Instance = TIM12;htim.Init.Period            = Period[_Mode];htim.Init.Prescaler         = 0;htim.Init.ClockDivision     = 0;htim.Init.CounterMode       = TIM_COUNTERMODE_UP;htim.Init.RepetitionCounter = 0;HAL_TIM_Base_Init(&htim);sConfig.OCMode     = TIM_OCMODE_PWM1;sConfig.OCPolarity = TIM_OCPOLARITY_LOW;/* 占空比50% */sConfig.Pulse = Pulse[_Mode];  if(HAL_TIM_OC_ConfigChannel(&htim, &sConfig, TIM_CHANNEL_1) != HAL_OK){Error_Handler(__FILE__, __LINE__);}/* 启动OC1 */if(HAL_TIM_OC_Start(&htim, TIM_CHANNEL_1) != HAL_OK){Error_Handler(__FILE__, __LINE__);}/* TIM12的TRGO用于触发DMAMUX的请求发生器 */sMasterConfig.MasterOutputTrigger = TIM_TRGO_OC1REF;sMasterConfig.MasterOutputTrigger2 = TIM_TRGO2_RESET;sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;HAL_TIMEx_MasterConfigSynchronization(&htim, &sMasterConfig);
}