CPU执行其他程序时为何没响应DMA的中断？

parkloey

通过串口给单片机发送命令，执行其他的指令，但是设想的前提是每隔一段时间来计算电流值，通过DMA buffer满了，CPU响应他的中断，如果电流过大，及时关断回路。但是实际执行的时候，CPU一直在执行那个case， 没来响应dma的中断。想问下是为什么？dma的中断优先级设置的是最高的，设置的是0组的，

armok.

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mon51

你把中断设置成4，16级中断，并把UART的中断级数填好：
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_4);


        NVIC_InitStructure.NVIC_IRQChannel = USART2_IRQn;
        NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority =rUART2;
        NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
        NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
        NVIC_Init(&NVIC_InitStructure);

mon51

                /* Enable DMA1 channel6 IRQ Channel */
                NVIC_InitStructure.NVIC_IRQChannel = DMA1_Channel1_IRQn;
                NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
                NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
                NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
                NVIC_Init(&NVIC_InitStructure);

mon51

这是STM32F151的采集ADC 数据，并发送的实例。

//分配16级中断的优先级        ,不设置自动按硬件优先级处理！ USART1_IRQChannel
void Set_NVIC_SUB(void){
        NVIC_InitTypeDef NVIC_InitStructure;
    // Configure the NVIC Preemption Priority Bits 2012-7-23 设置成4位=16级嵌套中断！
    NVIC_PriorityGroupConfig(NVIC_PriorityGroup_4);
        //NVIC_PriorityGroupConfig(NVIC_PriorityGroup_0);
       
          /* TIM3 IRQChannel enable */  
  NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority =4;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);
          /* TIM9 IRQChannel enable */  
  NVIC_InitStructure.NVIC_IRQChannel = TIM9_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 3;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);
       
        NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
        NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;
        NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
        NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
        NVIC_Init(&NVIC_InitStructure);

        /* Enable DMA1 channel6 IRQ Channel */
        NVIC_InitStructure.NVIC_IRQChannel = DMA1_Channel1_IRQn;
        NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
        NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
        NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
        NVIC_Init(&NVIC_InitStructure);

  /* TIM2 IRQChannel enable */  
  NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);
       
}

mon51

另外还要看DMA的中断初始化程序，以及中断处理程序。

mon51

/*********************************************************************
分配DMA3位DAC2服务！
输入Flash的数据表格地址，和长度！

**********************************************************************/
void DMA_SetChannel3_for_DAC2(const unsigned short *flashAdr,unsigned int cnt){
                DMA_InitTypeDef            DMA_InitStructure;       
       
                DMA_DeInit(DMA1_Channel3);
                DMA_InitStructure.DMA_PeripheralBaseAddr =(unsigned int)&(DAC->DHR12R2);   //指向右对齐寄存器12位
                DMA_InitStructure.DMA_MemoryBaseAddr =(u32)flashAdr;
                DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;
                DMA_InitStructure.DMA_BufferSize = cnt;
       
                DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
                DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
                DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
                DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
                DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;               //数据采用覆盖方式
                DMA_InitStructure.DMA_Priority = DMA_Priority_High;
                DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
                DMA_Init(DMA1_Channel3, &DMA_InitStructure);
                /* Enable DMA1 Channel3 */
                DMA_Cmd(DMA1_Channel3, ENABLE);
}

/*************************************************************************************
分配DMA2位DAC1服务！
输入Flash的数据表格地址，和长度！
**************************************************************************************/
void DMA_SetChannel2_for_DAC1(const unsigned short *flashAdr,unsigned int cnt){
                DMA_InitTypeDef            DMA_InitStructure;       
       
                DMA_DeInit(DMA1_Channel2);
                DMA_InitStructure.DMA_PeripheralBaseAddr =(unsigned int)&(DAC->DHR12R1);   //指向右对齐寄存器12位
                DMA_InitStructure.DMA_MemoryBaseAddr =(u32)flashAdr;
                DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;
                DMA_InitStructure.DMA_BufferSize = cnt;
       
                DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
                DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
                DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
                DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
                DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;               //数据采用覆盖方式
                DMA_InitStructure.DMA_Priority = DMA_Priority_High;
                DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
                DMA_Init(DMA1_Channel2, &DMA_InitStructure);
                /* Enable DMA1 Channel3 */
                DMA_Cmd(DMA1_Channel2, ENABLE);
}
/*************************************************************************************************
定时器6触发，同步输出DAC1，DAC2
必须事先生成双字节数据表在Flash里。 DAC_DHR12RD
**************************************************************************************************/
void DMA_Set_for_DAC12(unsigned int *flashAdr,unsigned int cnt){
       
                DMA_InitTypeDef            DMA_InitStructure;       
       
                DMA_DeInit(DMA1_Channel3);
                DMA_InitStructure.DMA_PeripheralBaseAddr =(unsigned int)&(DAC->DHR12RD);   //指向右对齐寄存器12位
                DMA_InitStructure.DMA_MemoryBaseAddr =(u32)flashAdr;
                DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;
                DMA_InitStructure.DMA_BufferSize = cnt;
       
                DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
                DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
                DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word;
                DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Word;
                DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;               //数据采用覆盖方式
                DMA_InitStructure.DMA_Priority = DMA_Priority_High;
                DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
                DMA_Init(DMA1_Channel3, &DMA_InitStructure);
                /* Enable DMA1 Channel3 */
                DMA_Cmd(DMA1_Channel3, ENABLE);
}
//**************************************************************************
//DMA for ADC
//DMA 1 为ADC-1-2服务
void DMA_SetChannel1_for_ADC1(unsigned short *pBuf,unsigned int cnt){
                DMA_InitTypeDef                    DMA_InitStructure;       
         /* DMA1 channel1 configuration */
                DMA_DeInit(DMA1_Channel1);
                DMA_InitStructure.DMA_PeripheralBaseAddr = (unsigned int)&(ADC1->DR);
                DMA_InitStructure.DMA_MemoryBaseAddr = (unsigned int)pBuf;
                DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;        //adc-->ram
                DMA_InitStructure.DMA_BufferSize = cnt;
                DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
                DMA_InitStructure.DMA_MemoryInc =DMA_MemoryInc_Enable;// DMA_MemoryInc_Disable;//当前存储器地址不变！
                DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
                DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
                DMA_InitStructure.DMA_Mode = DMA_Mode_Normal ;                         //传送完毕后产生中断，并停止！
                DMA_InitStructure.DMA_Priority = DMA_Priority_High;
                DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
                DMA_Init(DMA1_Channel1, &DMA_InitStructure);
                /* Enable DMA1 Channel6 Transfer Complete interrupt */
                DMA_ITConfig(DMA1_Channel1, DMA_IT_TC, ENABLE);       
       
                /* Enable DMA1 channel1 */
    DMA_Cmd(DMA1_Channel1, DISABLE);
}
//**************************************************************************
//DMA 1 为ADC-3ch-6ch服务
void DMA_SetChannel1_for_ADC3(unsigned short *pBuf,unsigned int cnt){
                DMA_InitTypeDef                    DMA_InitStructure;       
         /* DMA1 channel1 configuration */
                DMA_DeInit(DMA1_Channel1);
                DMA_InitStructure.DMA_PeripheralBaseAddr = (unsigned int)&(ADC1->DR);
                DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)&pBuf;
                DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;        //adc-->ram
                DMA_InitStructure.DMA_BufferSize = cnt;
                DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
                DMA_InitStructure.DMA_MemoryInc =DMA_MemoryInc_Enable;
                DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
                DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
                DMA_InitStructure.DMA_Mode = DMA_Mode_Circular ;                         //传送完毕后产生中断，并停止！
                DMA_InitStructure.DMA_Priority = DMA_Priority_High;
                DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
                DMA_Init(DMA1_Channel1, &DMA_InitStructure);
                /* Enable DMA1 Channel6 Transfer Complete interrupt */
                DMA_ITConfig(DMA1_Channel1, DMA_IT_TC, DISABLE);       
                /* Enable DMA1 channel1 */
                DMA_Cmd(DMA1_Channel1, ENABLE);
}

parkloey

mon51 发表于 2020-7-7 17:11
/*********************************************************************
分配DMA3位DAC2服务！
输入Flas ...

哈哈，我想错了，其实之前设置的是对的，只是我只是设置的一个标志位，之前觉得太多计算放在中断函数里面不太好，然后挪到其他的地方去了，然后现在计算电流值的函数在其他地方。设置了更高的优先级后，标志位其实是置位了，当然这个标志位就算置位，其他地方的函数也不会马上计算电流值显示出来了，怪不得我没看到电流值显示出来，还以为他没进到中断里面呢。现在改成其他方式处理了，已经解决了。谢谢你的代码！！！！！