STM32 SPI+DMA （HAL库）使用方法 - 好文

/* * SPI硬件初始化，内存地址初始化 */ static void Init(void) { uint8_t i; /*失能SPI1*/
HAL_SPI_DeInit(&hspi1);/*清空FpgaRevData内存*/ for(i=0;i<REV_MAX_NUM;i++) {
memset(FpgaRevData[i],0,FPGA_DATA_PAKET_LENGTH); } /*初始化内存指针*/ gWritePtr=0;
gReadPtr=0; /*使能SPI1*/ HAL_SPI_Init(&hspi1); /*SPI DMA初始化，并开启一次数据接收*/
HAL_SPI_Receive_DMA_INIT(&hspi1,FpgaRevData[gWritePtr],FPGA_DATA_PAKET_LENGTH);
}/* * SPI DMA初始化，并开启一次数据接收， * 关键是返回函数的初始化，DMA 源地址和目的地址的初始化，各标志位的清空与开启 *
该程序修改与HAL库的HAL_SPI_Receive_DMA函数 */ void
HAL_SPI_Receive_DMA_INIT(SPI_HandleTypeDef *hspi, uint8_t *pData, uint16_t
Size) { hspi->State = HAL_SPI_STATE_BUSY_RX; hspi->RxXferSize = Size;/*Init
field not used in handle to zero */ hspi->RxISR = NULL; /* Set the SPI Rx DMA
transfer complete callback */ hspi->hdmarx->XferCpltCallback =
SPI_DMAReceiveCplt;/* Enable the Rx DMA Stream */
HAL_DMA_Start_IT(hspi->hdmarx, (uint32_t)&hspi->Instance->DR,
(uint32_t)(uint8_t *)pData, Size);/* Check if the SPI is already enabled */ if
((hspi->Instance->CR1 &SPI_CR1_SPE) != SPI_CR1_SPE) {/* Enable SPI peripheral */
__HAL_SPI_ENABLE(hspi); }/* Enable the SPI Error Interrupt Bit */
SET_BIT(hspi->Instance->CR2, SPI_CR2_ERRIE);/* Enable Rx DMA Request */
SET_BIT(hspi->Instance->CR2, SPI_CR2_RXDMAEN); }/* * FPGA
SPI1数据接收函数，一次接收6个字节数据包 * 该程序修改与HAL库的HAL_DMA_Start_IT函数和HAL_SPI_Receive_DMA函数 */
__INLINEvoid FPGA_ReadBuffer(SPI_HandleTypeDef *hspi, uint8_t *DstAddress) { //
HAL_StatusTypeDef status = HAL_OK; /* calculate DMA base and stream number */
// DMA_Base_Registers *regs = (DMA_Base_Registers
*)(hspi->hdmarx)->StreamBaseAddress; /* Process locked */ //
__HAL_LOCK(hspi->hdmarx); // // if(HAL_DMA_STATE_READY == hspi->hdmarx->State)
// { /* Change DMA peripheral state */ // hspi->hdmarx->State =
HAL_DMA_STATE_BUSY; /* Clear DBM bit */ hspi->hdmarx->Instance->CR &=
(uint32_t)(~DMA_SxCR_DBM);/* Configure DMA Stream destination address */
hspi->hdmarx->Instance->M0AR = (uint32_t)(uint8_t *)DstAddress;/* Clear all
interrupt flags at correct offset within the register */ // regs->IFCR = 0x3FU
<< hspi->hdmarx->StreamIndex; /* Enable Common interrupts*/
hspi->hdmarx->Instance->CR |= DMA_IT_TC | DMA_IT_TE | DMA_IT_DME;
hspi->hdmarx->Instance->FCR |= DMA_IT_FE;/* Enable the Peripheral */
__HAL_DMA_ENABLE(hspi->hdmarx);// } // else // { // /* Process unlocked */ //
__HAL_UNLOCK(hspi->hdmarx); // // /* Return error status */ // status =
HAL_BUSY; // } /* Check if the SPI is already enabled */ //
if((hspi->Instance->CR1 &SPI_CR1_SPE) != SPI_CR1_SPE) // { // /* Enable SPI
peripheral */ // __HAL_SPI_ENABLE(hspi); // } /* Enable the SPI Error Interrupt
Bit */ SET_BIT(hspi->Instance->CR2, SPI_CR2_ERRIE|SPI_CR2_RXDMAEN); // /*
Enable Rx DMA Request */ // SET_BIT(hspi->Instance->CR2, SPI_CR2_RXDMAEN); //
return HAL_OK; } /* *SPI 返回函数，打开SPI DMA开关，一次接收6个字节数据包 */ void
HAL_SPI_RxCpltCallback(SPI_HandleTypeDef *hspi) {if(hspi==&hspi1) {
//HAL_SPI_DMAStop(hspi);//先关掉DMA /* Disable the SPI DMA Tx & Rx requests */
CLEAR_BIT(hspi->Instance->CR2, SPI_CR2_TXDMAEN | SPI_CR2_RXDMAEN);
//关掉DMA其实就是执行了这个操作 if((gWritePtr + 1 == gReadPtr) || (gWritePtr == REV_MAX_NUM
&& gReadPtr ==0))//我的数据存储在一个二维数组中，这里判断满了 return ; gWritePtr++; if
(gWritePtr==REV_MAX_NUM) gWritePtr=0;
FPGA_ReadBuffer(hspi,FpgaRevData[gWritePtr]); } }
当SPI DMA硬件初始化（SPI DMA mode为DMA_NORMAL）后，就可以开始一次初始

化HAL_SPI_Receive_DMA_INIT，之后，当有数据到来，SPI接收完成返回函数会被调用，在返回函数中，首先关掉DMA，接收到数据后，提供下一次接收数据的地址，重新打开DMA。

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