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我正在尝试使用 FreeRTOS（互斥体和流缓冲区）、DMA 和 USART3 实现 stm32f103 和 SIM900A 之间的通信。

我已启用 USART_IT_IDLE USART3 中断，以便能够检测 SIM900 传输结束并强制触发 DMA 传输完成中断以将数据从内存复制到 FreeRtos 的流缓冲区。

这篇文章说这是可能的。

/**
 * \brief       Global interrupt handler for USART2
 */
void USART2_IRQHandler(void) {
    /* Check for IDLE flag */
    if (USART2->SR & USART_FLAG_IDLE) {         /* We want IDLE flag only */
        /* This part is important */
        /* Clear IDLE flag by reading status register first */
        /* And follow by reading data register */
        volatile uint32_t tmp;                  /* Must be volatile to prevent optimizations */
        tmp = USART2->SR;                       /* Read status register */
        tmp = USART2->DR;                       /* Read data register */
        (void)tmp;                              /* Prevent compiler warnings */
        DMA1_Stream5->CR &= ~DMA_SxCR_EN;       /* Disabling DMA will force transfer complete interrupt if enabled */
    }
}

但我的调试器说：不

这是我的代码：

#define BUFF_SIZE 16

uint8_t RX_BUFFER[BUFF_SIZE] = {"\0"};
uint8_t TX_BUFFER[BUFF_SIZE] = {"\0"};

....

// USART TX channel
DMA_InitStruct.DMA_PeripheralBaseAddr = (uint32_t)&(USART3->DR);
DMA_InitStruct.DMA_MemoryBaseAddr = (uint32_t)&TX_BUFFER[0];
DMA_InitStruct.DMA_DIR = DMA_DIR_PeripheralDST;
DMA_InitStruct.DMA_BufferSize = sizeof(TX_BUFFER);
DMA_InitStruct.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStruct.DMA_MemoryInc = DMA_MemoryInc_Enable;
DMA_InitStruct.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
DMA_InitStruct.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;
DMA_InitStruct.DMA_Mode = DMA_Mode_Normal;
DMA_InitStruct.DMA_Priority = DMA_Priority_Low;
DMA_InitStruct.DMA_M2M = DMA_M2M_Disable;
DMA_Init(DMA1_Channel2, &DMA_InitStruct);
DMA_InitStruct.DMA_MemoryBaseAddr = (uint32_t)&RX_BUFFER[0];
DMA_InitStruct.DMA_DIR = DMA_DIR_PeripheralSRC;
DMA_InitStruct.DMA_BufferSize = sizeof(RX_BUFFER);
DMA_Init(DMA1_Channel3, &DMA_InitStruct);

// USART RX channel
DMA_InitStruct.DMA_MemoryBaseAddr = (uint32_t)&RX_BUFFER[0];
DMA_InitStruct.DMA_DIR = DMA_DIR_PeripheralSRC;
DMA_InitStruct.DMA_BufferSize = sizeof(RX_BUFFER);
DMA_Init(DMA1_Channel3, &DMA_InitStruct);

// Interrupts
USART_ITConfig(USART3, USART_IT_IDLE, ENABLE);
USART_DMACmd(USART3, USART_DMAReq_Tx | USART_DMAReq_Rx, ENABLE);
USART_Cmd(USART3, ENABLE);
DMA_ITConfig(DMA1_Channel3, DMA_IT_TC, ENABLE);
DMA_Cmd(DMA1_Channel3, ENABLE);

NVIC_InitTypeDef NVIC_InitStructure;
NVIC_InitStructure.NVIC_IRQChannel = USART3_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = configMAX_SYSCALL_INTERRUPT_PRIORITY + 10;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 4;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);

NVIC_InitStructure.NVIC_IRQChannel = DMA1_Channel3_IRQn;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3;
NVIC_Init(&NVIC_InitStructure);

....

void USART3_IRQHandler() {
    if (USART_GetITStatus(USART3, USART_IT_IDLE) == SET) {
        volatile uint32_t tmp = USART3->SR;
        tmp = USART3->DR;
        (void) tmp;


        // HERE interrupt should be fired!
        DMA1_Channel3->CCR &= (uint16_t)(~DMA_CCR1_EN); 
        USART_ClearITPendingBit(USART3, USART_IT_IDLE);
    }
}

void DMA1_Channel3_IRQHandler(void) {
    if (DMA_GetITStatus(DMA1_IT_TC3) == SET) {
        uint8_t len = BUFF_SIZE - DMA1_Channel3->CNDTR;
        BaseType_t xHigherPriorityTaskWoken = pdFALSE;
        xStreamBufferSendFromISR(xUSART3ReceiveStreamBuffer, &RX_BUFFER, len, &xHigherPriorityTaskWoken);
        for (uint8_t i = 0; i < len; i++) {
            RX_BUFFER[i] = '\0';
        }

        DMA1_Channel3->CNDTR = BUFF_SIZE;
        DMA_Cmd(DMA1_Channel3, ENABLE);
        DMA_ClearITPendingBit(DMA1_IT_TC3);
    }
}

为什么我不能强制 DMA1_IT_TC3 中断？还是可以强制在STM32F103上？

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0 回答 0