使用STM32F103微控制器(Cortex-M3)重新编程DMA起始地址

yjghlzjz  于 2023-08-03  发布在  其他
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下面的IRQ处理程序会耗尽USART 3的32字节数据。第一个IRQ TC事件读取前6个字节,然后重新编程DMA引擎以读取最后24个字节。第二个TC将其重新编码以再次读取报头。此方法将允许使用DMA的可变长度消息。但是,我似乎无法更改DMA起始地址。我想能够存储在一个单独的缓冲区,但它只是在收到每个消息后,第一个缓冲区写的每一个消息。我做错了什么?微控制器是STM32F103 ze(Cortex-M3)。

void DMA1_Channel3_IRQHandler(void)
{
    uint32_t tmpreg = 0;
     /* Test on DMA1 Channel3 Transfer Complete interrupt */
     if(DMA_GetITStatus(DMA1_IT_TC3)) 
     {
          if (rx3_dma_state == RECIEVE_HEADER )
          {
               DMA_Cmd(DMA1_Channel3, DISABLE);/* Disable DMA1_Channel2 transfer*/
               // Now that have received the header. Configure the DMA engine to receive
               // the data portion of the message
               DMA_SetCurrDataCounter(DMA1_Channel3,26);
               DMA_Cmd(DMA1_Channel3, ENABLE);
          } else if ( rx3_dma_state == RECIEVE_MSG )
          {
               //CurrDataCounterEnd3 = DMA_GetCurrDataCounter(DMA1_Channel3);
               DMA_Cmd(DMA1_Channel3, DISABLE);
               /* Get Current Data Counter value after complete transfer */
               USART3_Rx_DMA_Channel_Struct->CMAR = (uint32_t) RxBuffer3LookUp[rx_buffer_index];
               DMA_SetCurrDataCounter(DMA1_Channel3, 6);
               DMA_Cmd(DMA1_Channel3,ENABLE);
               // Set up DMA to write into the next buffer slot (1 of 8)
               ++rx_buffer_index;
               rx_buffer_index %= 8;
          }
          /* Clear DMA1 Channel6 Half Transfer, Transfer Complete and Global interrupt pending bits */
          DMA_ClearITPendingBit(DMA1_IT_GL3);
     }      
     // Update the state to read fake header of 6 bytes
     // or to read the fake data section of the message 26 bytes
     ++rx3_dma_state;
     rx3_dma_state %= 2;
     isr_sem_send(dma_usart3_rx_sem);
}

字符串

1l5u6lss

1l5u6lss1#

你就说:
...对DMA引擎重新编程,以读入最后24个字节。
但是你的代码说:
DMA_设置当前数据计数器(DMA 1_通道3,26);
是这样吗?是24还是26?

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