串口空闲中断接收不定长数据
空闲中断是接受数据后出现一个byte的高电平(空闲)状态,就会触发空闲中断.并不是空闲就会一直中断,准确的说应该是上升沿（停止位）后一个byte，如果一直是低电平是不会触发空闲中断的（会触发break中断）。
串口初始化部分采用stm32cubemx软件生成。
一、串口空闲中断加DMA方式接收
在串口初始化时开启空闲中断和DMA接收
#define BUFFER_SIZE 512//不定长数据的最大长度，设置为100则最大长度为100volatile int rx_len=0;//接收数据长度volatile uint8_t recv_end_flag= 0; //接收完成标记位uint8_t rx_buffer[BUFFER_SIZE]={0}; //接收缓存uint8_t rx_count=0;
void MX_USART1_UART_Init(void){/*省略自动生成部分代码*//* USER CODE BEGIN USART1_MspInit 1 */__HAL_UART_ENABLE_IT(&huart1,UART_IT_IDLE);HAL_UART_Receive_DMA(&huart1, (uint8_t*)rx_buffer, BUFFER_SIZE); /* USER CODE END USART1_MspInit 1 */ }
必须添加，不然收不到第一帧数据，不能加在HAL_UART_MspInit（）函数里面，会导致第一帧数据为0，且为最大长度的数据。
void UART_IRQ(UART_HandleTypeDef *huart)/*空闲中断加DMA方式*/{uint8_t ret = 0;if(huart->Instance == USART1){if(__HAL_UART_GET_FLAG(&huart1, UART_FLAG_IDLE) != RESET){recv_end_flag = 1;__HAL_UART_CLEAR_IDLEFLAG(&huart1);HAL_UART_DMAStop(&huart1);rx_len =BUFFER_SIZE - __HAL_DMA_GET_COUNTER(&hdma_usart1_rx);HAL_UART_Receive_DMA(&huart1, (uint8_t*)rx_buffer, BUFFER_SIZE); }}}
串口中断函数
extern void UART_IRQ(UART_HandleTypeDef *huart);void USART1_IRQHandler(void){/* USER CODE BEGIN USART1_IRQn 0 *//* USER CODE END USART1_IRQn 0 */HAL_UART_IRQHandler(&huart1);/* USER CODE BEGIN USART1_IRQn 1 */UART_IRQ(&huart1);/* USER CODE END USART1_IRQn 1 */}
二、串口空闲中断加接收中断方式`
初始化时开启空闲和接收中断
void HAL_UART_MspInit(UART_HandleTypeDef* uartHandle){/*省略自动生成部分代码*//* USER CODE BEGIN USART1_MspInit 1 */__HAL_UART_ENABLE_IT(&huart1,UART_IT_IDLE);__HAL_UART_ENABLE_IT(&huart1,UART_IT_RXNE);/* USER CODE END USART1_MspInit 1 */ }
void UART_IRQ(UART_HandleTypeDef *huart)/*接收和空闲中断方式*/{if(__HAL_UART_GET_FLAG(huart, UART_FLAG_RXNE) != RESET){if(recv_end_flag == UART_RX_STATE_READY){//__HAL_UART_ENABLE_IT(huart, UART_IT_IDLE);/*初始化没开启就进中断再开启*/recv_end_flag = UART_RX_STATE_START;;rx_len = 0;rx_buffer[rx_len] = huart->Instance->DR;rx_len++;}else if(recv_end_flag == UART_RX_STATE_START){rx_buffer[rx_len] = huart->Instance->DR;rx_len++;}__HAL_UART_CLEAR_FLAG(huart, UART_FLAG_RXNE);}if(__HAL_UART_GET_FLAG(huart, UART_FLAG_IDLE) != RESET){__HAL_UART_CLEAR_IDLEFLAG(&huart1);__HAL_UART_DISABLE_IT(huart, UART_IT_RXNE);__HAL_UART_DISABLE_IT(huart, UART_IT_IDLE);recv_end_flag = UART_RX_STATE_DEAL;}}
三、数据处理
**/*DMA加空闲中断方式*/**while(1){if(recv_end_flag == 1){Debugprintf("接收到数据个数：%d\r\n",rx_len);HAL_UART_Transmit(&huart3, rx_buffer, rx_len, 1000);/*通过串口转发出去*/rx_len = 0;recv_end_flag = 0;/*清标志位*/memset(rx_buffer, 0, BUFFER_SIZE);/*清buff*/}}**/*串口空闲中断加接收中断方式*/**while(1){if(end_flag ==UART_RX_STATE_DEAL){end_flag = UART_RX_STATE_READY;HAL_UART_Transmit(&huart1, (uint8_t*)rec_buff, rx_len, 0XFFFF);while(HAL_UART_GetState(&huart1) == HAL_UART_STATE_BUSY);rx_len = 0;memset(rec_buff, 0, sizeof(rec_buff));__HAL_UART_ENABLE_IT(&huart1, UART_IT_RXNE);__HAL_UART_ENABLE_IT(&huart1, UART_IT_IDLE);}/* USER CODE END WHILE *//* USER CODE BEGIN 3 */}/* USER CODE END 3 */}
