STM32L4R5的DMAMUX异常

浮云流水zjf 提问时间：2019-5-29 17:50 /

问答
是否解决:

__HAL_RCC_DMA1_CLK_ENABLE();
__HAL_RCC_DMAMUX1_CLK_ENABLE();
/*##-3- Configure the DMA ##################################################*/
/* Configure the DMA handler for Transmission process (DMA的发送通道)*/
hdma_tx.Instance                = DMA1_Channel5; //DMA1_Channel3
hdma_tx.Init.Request          = DMA_REQUEST_GENERATOR0; // DMA_REQUEST_SPI2_TX
hdma_tx.Init.Direction          = DMA_MEMORY_TO_PERIPH; //内存到外设
hdma_tx.Init.PeriphInc          = DMA_PINC_DISABLE;
hdma_tx.Init.MemInc             = DMA_MINC_ENABLE; //DMA_MINC_ENABLE  DMA_MINC_DISABLE
hdma_tx.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE; //DMA_PDATAALIGN_WORD  DMA_PDATAALIGN_BYTE
hdma_tx.Init.MemDataAlignment = DMA_MDATAALIGN_BYTE; // DMA_MDATAALIGN_BYTE  DMA_MDATAALIGN_WORD
hdma_tx.Init.Mode             = DMA_CIRCULAR; //由 DMA_NORMAL 改为循环发送 DMA_CIRCULAR
hdma_tx.Init.Priority          = DMA_PRIORITY_HIGH;

HAL_DMA_Init(&hdma_tx);
/* Associate the initialized DMA handle to the the SPI handle */
__HAL_LINKDMA(&ads1298_hspi, hdmatx, hdma_tx);
/* Register Error Callback */
HAL_DMA_RegisterCallback(&hdma_tx, HAL_DMA_XFER_ERROR_CB_ID, &HAL_TransferError);

/* NVIC configuration for DMA transfer complete interrupt*/
HAL_NVIC_SetPriority(DMA1_Channel5_IRQn, 3, 0);
HAL_NVIC_EnableIRQ(DMA1_Channel5_IRQn);

/*##-3- Configure and enable the DMAMUX Request generator  ####################(配置和使能DMAMUX请求生成器)*/
dmamux_ReqGenParams.SignalID  = HAL_DMAMUX1_REQUEST_GEN_EXTI8; /* External request signal is EXTI0 signal       HAL_DMAMUX1_REQ_GEN_EXTI8*/

dmamux_ReqGenParams.Polarity  = HAL_DMAMUX_REQUEST_GEN_FALLING; /* External request signal edge is Rising  */
dmamux_ReqGenParams.RequestNumber = 27;                            /* 1 requests on each edge of the external request signal  27*/

HAL_DMAEx_ConfigMuxRequestGenerator(ads1298_hspi.hdmatx, &dmamux_ReqGenParams);

/* NVIC configuration for DMAMUX request generator overrun errors*/
HAL_NVIC_SetPriority(DMAMUX1_OVR_IRQn, 4, 0);
HAL_NVIC_EnableIRQ(DMAMUX1_OVR_IRQn);

HAL_DMAEx_EnableMuxRequestGenerator (ads1298_hspi.hdmatx);
HAL_SPI_Transmit_DMA(&ads1298_hspi, adTxBuffer, 27);

   代码如上，要配置的功能是DMAMUX检测到PF8的下降沿，就通过通过DMA1的DMA1_Channel5向SPI2->DR发送27个0xAA,实测发现：
   dmamux_ReqGenParams.RequestNumber在的值[1,5]范围内时，每次中断触发时，DMA1_Channel5能够发送[1,5]个数，但在[6,32]范围内时，发送的个数就不够了，严重丢数。查了下库的寄存器配置，没有问题。现在不知道是自己调用的不对，还是其他问题？各位大神路过的帮看看！谢谢