STM32串口接收中断疑问 求解?

如果丢失一个，会把后面的数据连接起来。楼主可以考虑使用空闲中断或者中断队列的方式，将所有接收到的数据放入到缓冲区中，保证数据的完整性。

首先非常感谢您的耐心解答，我也看了一些空闲中断的介绍文档，但是没有用过这种方式，还有一点儿疑问。我的硬件是STM32f405，工作频率168M，有两路串口要不停的接收帧协议数据，每一帧7个字节，波特率是2M，数据量应该是特别大的，因为我需要解析帧协议，所以想采用单字节接收中断的方式，也就是HAL_UART_Receive_IT(&huart1,(uint8_t *)&Uart1_Rxdata, 1); 这种方式是不是不太好，不是最佳的方式？是不是会让CPU负担很重？如果是的话，能通过什么方式可以测出CPU现在负担有多重？（是不是可以通过在中断回调函数的起始和终点处设置IO电平翻转来看中断函数执行时间和频率，去确定CPU当前的负担？） 对于我这种2M波特率，需要帧协议解析（帧长度固定）的情况，最佳的方式是？

考虑使用串口空闲中断加DMA的方式接收

USART+DMA+IDLE组合就可以满足你的要求，当然USART+TIM组合也可以，建议前者

相邻两帧之间的时间1s，应该足够mcu解析。1. 可以考虑DMA接收结合空闲中断，库函数如下，鉴于每一帧字节数目可能变动，所以DMA传输的字节要最大，因此，退出条件或者是接收到规定数目字节的数据或者Rx空闲。 /** * @brief Receive an amount of data in DMA mode till either the expected number * of data is received or an IDLE event occurs. * @note Reception is initiated by this function call. Further progress of reception is achieved thanks * to DMA services, transferring automatically received data elements in user reception buffer and * calling registered callbacks at half/end of reception. UART IDLE events are also used to consider * reception phase as ended. In all cases, callback execution will indicate number of received data elements. * @note When the UART parity is enabled (PCE = 1), the received data contain * the parity bit (MSB position). * @note When UART parity is not enabled (PCE = 0), and Word Length is configured to 9 bits (M1-M0 = 01), * the received data is handled as a set of uint16_t. In this case, Size must indicate the number * of uint16_t available through pData. * @param huart UART handle. * @param pData Pointer to data buffer (uint8_t or uint16_t data elements). * @param Size Amount of data elements (uint8_t or uint16_t) to be received. * @retval HAL status */ HAL_StatusTypeDef HAL_UARTEx_ReceiveToIdle_DMA(UART_HandleTypeDef *huart, uint8_t *pData, uint16_t Size) { HAL_StatusTypeDef status; (略) 2. 回调函数如下，其中返回Size为实际接收到的数据，接收缓冲从0到Size-1就是数据，解析协议应该在这里执行。 /** * @brief Reception Event Callback (Rx event notification called after use of advanced reception service). * @param huart UART handle * @param Size Number of data available in application reception buffer (indicates a position in * reception buffer until which, data are available) * @retval None */ __weak void HAL_UARTEx_RxEventCallback(UART_HandleTypeDef *huart, uint16_t Size) { /* Prevent unused argument(s) compilation warning */ UNUSED(huart); UNUSED(Size); /* NOTE : This function should not be modified, when the callback is needed, the HAL_UARTEx_RxEventCallback can be implemented in the user file. */ }