c语言中0x1u是多少,HAL库源文件stm32h7xx

c语言中0x1u是多少,HAL库源文件stm32h7xx

自己写了个BDMA双缓冲配置的函数，验证了一下，BDMA双缓冲还是可以用的。手册还是比较靠谱的

。

不想改动官方库，这样以后升级库也方便，以下代码放在单独的文件里。

#define BDMA_CCR_DBM_Pos        (15U)

#define BDMA_CCR_DBM_Msk        (0x1U << BDMA_CCR_DBM_Pos)                      /*!< 0x00008000 */

#define BDMA_CCR_DBM            BDMA_CCR_DBM_Msk                                /*!< DBM bits(Double-Buffer Mode)*/

#define BDMA_CCR_CT_Pos         (16U)

#define BDMA_CCR_CT_Msk         (0x1U << BDMA_CCR_CT_Pos)                      /*!< 0x00010000 */

#define BDMA_CCR_CT             BDMA_CCR_CT_Msk                                /*!< CT bits(Current Target Memory)*/

HAL_StatusTypeDef HAL_BDMAEx_MultiBufferStart_IT(DMA_HandleTypeDef *hdma, uint32_t SrcAddress, uint32_t DstAddress, uint32_t SecondMemAddress, uint32_t DataLength)

{

HAL_StatusTypeDef status = HAL_OK;

__IO uint32_t *ifcRegister_Base = NULL; /* DMA Stream Interrupt Clear register */

/* Check the parameters */

assert_param(IS_DMA_BUFFER_SIZE(DataLength));

/* Memory-to-memory transfer not supported in double buffering mode */

if(hdma->Init.Direction == DMA_MEMORY_TO_MEMORY)

{

hdma->ErrorCode = HAL_DMA_ERROR_NOT_SUPPORTED;

return HAL_ERROR;

}

/* Process locked */

__HAL_LOCK(hdma);

if(HAL_DMA_STATE_READY == hdma->State)

{

/* Change DMA peripheral state */

hdma->State = HAL_DMA_STATE_BUSY;

/* Initialize the error code */

hdma->ErrorCode = HAL_DMA_ERROR_NONE;

/* Enable the Double buffer mode */

((BDMA_Channel_TypeDef   *)hdma->Instance)->CCR |= (uint32_t)BDMA_CCR_DBM;

/* Configure DMA Stream destination address */

*((uint32_t*)(&((BDMA_Channel_TypeDef   *)hdma->Instance)->CMAR)+1) = SecondMemAddress;

/* Configure the source, destination address and the data length */

/* Configure DMA Stream data length */

((BDMA_Channel_TypeDef   *)hdma->Instance)->CNDTR = DataLength;

/* Peripheral to Memory */

if((hdma->Init.Direction) == DMA_MEMORY_TO_PERIPH)

{

/* Configure DMA Stream destination address */

((BDMA_Channel_TypeDef   *)hdma->Instance)->CPAR = DstAddress;

/* Configure DMA Stream source address */

((BDMA_Channel_TypeDef   *)hdma->Instance)->CMAR = SrcAddress;

}

/* Clear all flags */

BDMA->IFCR  |= (BDMA_ISR_GIF0 << hdma->StreamIndex);

/* Clear the DMAMUX synchro overrun flag */

hdma->DMAmuxChannelStatus->CFR = hdma->DMAmuxChannelStatusMask;

if(hdma->DMAmuxRequestGen != 0U)

{

/* Clear the DMAMUX request generator overrun flag */

hdma->DMAmuxRequestGenStatus->RGCFR = hdma->DMAmuxRequestGenStatusMask;

}

/* Enable Common interrupts*/

MODIFY_REG(((BDMA_Channel_TypeDef   *)hdma->Instance)->CCR, (BDMA_CCR_TCIE | BDMA_CCR_HTIE | BDMA_CCR_TEIE), (BDMA_CCR_TCIE | BDMA_CCR_TEIE));

if(hdma->XferHalfCpltCallback != NULL)

{

/*Enable Half Transfer IT if corresponding Callback is set*/

((BDMA_Channel_TypeDef   *)hdma->Instance)->CCR  |= BDMA_CCR_HTIE;

}

/* Check if DMAMUX Synchronization is enabled*/

if((hdma->DMAmuxChannel->CCR & DMAMUX_CxCR_SE) != 0)

{

/* Enable DMAMUX sync overrun IT*/

hdma->DMAmuxChannel->CCR |= DMAMUX_CxCR_SOIE;

}

if(hdma->DMAmuxRequestGen != 0U)

{

/* if using DMAMUX request generator, enable the DMAMUX request generator overrun IT*/

/* enable the request gen overrun IT*/

hdma->DMAmuxRequestGen->RGCR |= DMAMUX_RGxCR_OIE;

}

/* Enable the peripheral */

__HAL_DMA_ENABLE(hdma);

}

else

{

/* Set the error code to busy */

hdma->ErrorCode = HAL_DMA_ERROR_BUSY;

/* Return error status */

status = HAL_ERROR;

}

return status;

}

另外需要注意的是，官方库的DMA中断处理中，没有针对BDMA双缓冲的处理，但是可以自己在DMA传输完成中断回调中判断当前使用的缓冲区自行处理。

static void HAL_TransferCplt(DMA_HandleTypeDef *hdma)

{

if((((BDMA_Channel_TypeDef   *)hdma->Instance)->CCR & BDMA_CCR_CT_Msk) != RESET) {

//...

} else {

//...

}

}

希望可以帮到需要用这个功能的人。