本帖最后由 wling597074509 于 2023-8-28 09:25 编辑
我想采用DMA改变PWM波的占空比,代码如下,将DMA模式设置为循环模式能够输出设定的占空比的波形,但是改成NORMAL模式就什么输出也没有了,调试时定时器CCR2的值也没有任何变化,想请教下是什么原因了?
[C] 纯文本查看 复制代码 #define NUM 24
ALIGN_32BYTES (uint32_t send_Buf[NUM] )= {0};
void main(void)
{
MX_TIM4_Init();
for(uint8_t i=0;i<NUM;i++)
{
send_Buf[i]=5*i+10;
}
SCB_CleanDCache_by_Addr((uint32_t *) send_Buf, sizeof(send_Buf) );
while(1)
{
HAL_TIM_PWM_Start_DMA(&htim4, TIM_CHANNEL_2, (uint32_t *)send_Buf, NUM);
bsp_DelayMS(100);
}
static void MX_TIM4_Init(void)
{
TIM_MasterConfigTypeDef sMasterConfig = {0};
TIM_OC_InitTypeDef sConfigOC = {0};
/*GPIO 初始化*/
GPIO_InitTypeDef GPIO_InitStruct = {0};
__HAL_RCC_GPIOD_CLK_ENABLE();
// HAL_GPIO_WritePin(GPIOD, GPIO_PIN_13, GPIO_PIN_RESET);
/*Configure GPIO pin : PD13 */
GPIO_InitStruct.Pin = GPIO_PIN_13;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
GPIO_InitStruct.Alternate = GPIO_AF2_TIM4;
HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);
/*DMA初始化*/
__HAL_RCC_DMA1_CLK_ENABLE();
hdma_tim4_ch2.Instance = DMA1_Stream0;
hdma_tim4_ch2.Init.Request = DMA_REQUEST_TIM4_CH2;
hdma_tim4_ch2.Init.Direction = DMA_MEMORY_TO_PERIPH;
hdma_tim4_ch2.Init.PeriphInc = DMA_PINC_DISABLE;
hdma_tim4_ch2.Init.MemInc = DMA_MINC_ENABLE;
hdma_tim4_ch2.Init.PeriphDataAlignment = DMA_PDATAALIGN_WORD;
hdma_tim4_ch2.Init.MemDataAlignment = DMA_MDATAALIGN_WORD;
hdma_tim4_ch2.Init.Mode = DMA_NORMAL;
hdma_tim4_ch2.Init.Priority = DMA_PRIORITY_HIGH;
hdma_tim4_ch2.Init.FIFOMode = DMA_FIFOMODE_DISABLE;
hdma_tim4_ch2.Init.FIFOThreshold = DMA_FIFO_THRESHOLD_FULL;
hdma_tim4_ch2.Init.MemBurst = DMA_MBURST_SINGLE;
hdma_tim4_ch2.Init.PeriphBurst = DMA_PBURST_SINGLE;
__HAL_LINKDMA(&htim4,hdma[TIM_DMA_ID_CC2],hdma_tim4_ch2);
if (HAL_DMA_Init(htim4.hdma[TIM_DMA_ID_CC2]) != HAL_OK)
{
Error_Handler(__FILE__, __LINE__);
}
HAL_NVIC_SetPriority(DMA1_Stream0_IRQn, 0, 0);
HAL_NVIC_EnableIRQ(DMA1_Stream0_IRQn);
__HAL_RCC_TIM4_CLK_ENABLE();
/*TIM4使用的是APB1时钟,因为APB1 prescaler != 1, 所以 APB1上的TIM4CLK = APB1 x 2 = 200MHz;*/
/*TIM4CLK = 200MHz/(Period + 1) / (Prescaler + 1)*/
htim4.Instance = TIM4;
htim4.Init.Prescaler = 0;
htim4.Init.CounterMode = TIM_COUNTERMODE_UP;
htim4.Init.Period = 249;
htim4.Init.RepetitionCounter=0;
htim4.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
htim4.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
if (HAL_TIM_PWM_Init(&htim4) != HAL_OK)
{
Error_Handler(__FILE__, __LINE__);
}
sConfigOC.OCMode = TIM_OCMODE_PWM1;
sConfigOC.Pulse = 0;
sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
sConfigOC.OCIdleState = TIM_OCIDLESTATE_RESET;
sConfigOC.OCNIdleState = TIM_OCNIDLESTATE_RESET;
if (HAL_TIM_PWM_ConfigChannel(&htim4, &sConfigOC, TIM_CHANNEL_2) != HAL_OK)
{
Error_Handler(__FILE__, __LINE__);
}
}
/**
* @brief This function handles DMA1 stream0 global interrupt.
*/
void DMA1_Stream0_IRQHandler(void)
{
HAL_DMA_IRQHandler(htim4.hdma[TIM_DMA_ID_CC2]);
}
// PWM DMA 完成回调函数
void HAL_TIM_PWM_PulseFinishedCallback(TIM_HandleTypeDef *htim)
{
HAL_TIM_PWM_Stop_DMA(&htim4, TIM_CHANNEL_2);
}
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