STM32F103串口发送中断中断可以进就是引脚没反应？

linbo411 · 发表于 2015-12-30 09:38:24

用STM32F103 RS485通信接收和发送都是用的中断，接收正常，发送中断也进，标志都正常就是发不出去，测引脚没波形

NVIC_InitTypeDef NVIC_InitStructure;

/* Set the Vector Table base location at 0x08000000 */
NVIC_SetVectorTable(NVIC_VectTab_FLASH, 0x0);

/* Configure the NVIC Preemption Priority Bits */
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);// 分组2 抢占2位4级 ,响应2位4级

      // 频率输出抢占优先级0,响应优先级0
      NVIC_InitStructure.NVIC_IRQChannel = TIM4_IRQn;                                                       // TIM4中断
      NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;                // 先占优先级0级
      NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;                                        // 响应优先级0级
      NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;                                                       // IRQ通道被使能
      NVIC_Init(&NVIC_InitStructure);                                                                                                                         // 初始化NVIC寄存器

      // 测量控制外部中断抢占优先级1，响应优先级 0
  NVIC_InitStructure.NVIC_IRQChannel = EXTI15_10_IRQn;
      NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;                // 抢占优先级1
      NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;                                              // 响应优先级0
      NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
      NVIC_Init(&NVIC_InitStructure);

      // 基准信号和定时中断抢占优先级 2 响应优先级 0
  NVIC_InitStructure.NVIC_IRQChannel = TIM1_CC_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);

      // 串口1中断抢占优先级3 响应优先级 0
  NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;             // 通道设置为串口1中断
      NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1; // 抢占优先级3
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;                         // 中断响应优先级0
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;                                        // 打开中断
  NVIC_Init(&NVIC_InitStructure);

中断优先级分组，上面的分组除了串口，其他3个去掉一个发送就正常，全开可以进中断就是发送不了？

下面是我串口程序
void USART1_Configuration(void)
{
      USART_InitTypeDef USART_InitStructure;

      USART_InitStructure.USART_BaudRate = 9600;
      USART_InitStructure.USART_WordLength = USART_WordLength_8b;
      USART_InitStructure.USART_StopBits = USART_StopBits_1;
      USART_InitStructure.USART_Parity = USART_Parity_No;
      USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
      USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
      USART_Init(USART1, &USART_InitStructure);
  USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);// 开启接收中断
      USART_Cmd(USART1, ENABLE);// 使能串口
// 如下语句解决第1个字节无法正确发送出去的问题
  USART_ClearFlag(USART1, USART_FLAG_TC);    // 清标志
      CS485_RXD_H;                                                                                                                               // RS485接收状态
}

void USART1_IRQHandler(void)
{
  uint8_t  dat;

  if(USART_GetITStatus(USART1, USART_IT_RXNE) != RESET) //接收中断
  {
dat = USART_ReceiveData(USART1);
if(dat == 0x63)
            {
                     CS485_TXD_L;                                                             // RS485转到发送状态
                     dat = 0;
                     TxBuff[0] = 0xAA;
                     TxBuff[1] = 0xAB;
                     TxBuff[2] = 0xAC;
   NTxBuff = 0;             // 发送数据字节计数
   TX_Number = 3;             // 发送字节数据
                     USART_ITConfig(USART1,USART_IT_TXE,ENABLE);// 开启DR数据为空（以及转移到移位寄存器SR)中断
            }
  }
      else if(USART_GetITStatus( USART1, USART_IT_TC ) != RESET)// 发送完成中断
      {
            CS485_RXD_H;                                                                                                                                              // RS485转到接收状态
            USART_ClearITPendingBit(USART1,USART_IT_TC );       // 清除USART1的发送完一字节中断
      }
      else if(USART_GetFlagStatus(USART1,USART_IT_TXE) == RESET)// DR数据为空中断
      {
            USART_ClearITPendingBit(USART1,USART_IT_TXE );       // 清除USART1的发送完一字节中断
            if(NTxBuff <TX_Number)
            {
                     USART_SendData(USART1,TxBuff[NTxBuff++]); // 连续发送数据
            }
            else// 最后一字节
            {
                     USART_ITConfig(USART1,USART_IT_TXE,DISABLE); // 关闭DR数据为空中断
                     USART_ITConfig(USART1,USART_IT_TC, ENABLE);  // 开启发送完成中断
            }
      }
}