STM32G431收发CAN

1.硬件连接

PB8作为CAN_RX，PB9作为CAN_TX，连接一个CAN收发器TJA1051T/3

2. CubeMX里配置CAN

设置连接FDCAN1的参数，使用1个标准过滤器，波特率位500K

使能FDCAN1的中断

3 自动生成代码

3.1 初始化

static void MX_FDCAN1_Init(void)
{/* USER CODE BEGIN FDCAN1_Init 0 */__HAL_RCC_FDCAN_CLK_ENABLE();/* USER CODE END FDCAN1_Init 0 *//* USER CODE BEGIN FDCAN1_Init 1 *//* USER CODE END FDCAN1_Init 1 */hfdcan1.Instance = FDCAN1;hfdcan1.Init.ClockDivider = FDCAN_CLOCK_DIV2;hfdcan1.Init.FrameFormat = FDCAN_FRAME_CLASSIC;hfdcan1.Init.Mode = FDCAN_MODE_NORMAL;hfdcan1.Init.AutoRetransmission = DISABLE;hfdcan1.Init.TransmitPause = DISABLE;hfdcan1.Init.ProtocolException = DISABLE;hfdcan1.Init.NominalPrescaler = 2;hfdcan1.Init.NominalSyncJumpWidth = 1;hfdcan1.Init.NominalTimeSeg1 = 14;hfdcan1.Init.NominalTimeSeg2 = 3;hfdcan1.Init.DataPrescaler = 1;hfdcan1.Init.DataSyncJumpWidth = 1;hfdcan1.Init.DataTimeSeg1 = 1;hfdcan1.Init.DataTimeSeg2 = 1;hfdcan1.Init.StdFiltersNbr = 1;hfdcan1.Init.ExtFiltersNbr = 0;hfdcan1.Init.TxFifoQueueMode = FDCAN_TX_FIFO_OPERATION;if (HAL_FDCAN_Init(&hfdcan1) != HAL_OK){Error_Handler();}/* USER CODE BEGIN FDCAN1_Init 2 */CAN_SetFilter();HAL_FDCAN_Start(&hfdcan1);// Activate notificationsHAL_FDCAN_ActivateNotification(&hfdcan1, FDCAN_IT_TX_FIFO_EMPTY,0);HAL_FDCAN_ActivateNotification(&hfdcan1, FDCAN_IT_RX_FIFO0_NEW_MESSAGE,0);/* USER CODE END FDCAN1_Init 2 */}

手工增加：

• FDCAN时钟使能 __HAL_RCC_FDCAN_CLK_ENABLE();
• 过滤器设置 CAN_SetFilter();
• 激活中断信号，发送完成和FIFO0收到新消息
• 启动 HAL_FDCAN_Start(&hfdcan1);

3.2 过滤器设置

/* USER CODE BEGIN 4 */
void CAN_SetFilter()
{FDCAN_FilterTypeDef sFilterConfig;// 初始化过滤器配置结构sFilterConfig.IdType=FDCAN_STANDARD_ID;sFilterConfig.FilterIndex=0;sFilterConfig.FilterType=FDCAN_FILTER_DUAL;sFilterConfig.FilterConfig=FDCAN_FILTER_TO_RXFIFO0;sFilterConfig.FilterID1=0x11;sFilterConfig.FilterID2=0x22;if (HAL_FDCAN_ConfigFilter(&hfdcan1, &sFilterConfig) != HAL_OK){// 处理错误Error_Handler();}//全局过滤器设置,如果包含上述条件的帧则通过HAL_FDCAN_ConfigGlobalFilter(&hfdcan1,FDCAN_REJECT, FDCAN_REJECT, FDCAN_FILTER_REMOTE, FDCAN_FILTER_REMOTE);
}

• 采用一个标准过滤器，过滤器号：0， 过滤类型FDCAN_FILTER_DUAL，就是把FilterID1和FilterID2当成2个CAN ID，过滤器配置为FDCAN_FILTER_TO_RXFIFO0，即把那两个CANID的消息存入RX FIFO0
• 记得进行全局过滤设置，其函数原型如下：
• 
  本例中拒绝不匹配的标准帧，拒绝不匹配的扩展帧，接收过滤后的标准远程帧，接收过滤后的扩展远程帧。

3.3 中断处理

void FDCAN1_IT0_IRQHandler(void)
{/* USER CODE BEGIN FDCAN1_IT0_IRQn 0 */CAN_Rcv_IR();/* USER CODE END FDCAN1_IT0_IRQn 0 */HAL_FDCAN_IRQHandler(&hfdcan1);/* USER CODE BEGIN FDCAN1_IT0_IRQn 1 *//* USER CODE END FDCAN1_IT0_IRQn 1 */
}

加入接收中断处理函数：CAN_Rcv_IR();

void CAN_Rcv_IR()
{if (__HAL_FDCAN_GET_FLAG(&hfdcan1, FDCAN_FLAG_RX_FIFO0_NEW_MESSAGE)){	       FDCAN_RxHeaderTypeDef pHeader;uint8_t pData[64];// 循环处理新消息while (HAL_FDCAN_GetRxFifoFillLevel(&hfdcan1,FDCAN_RX_FIFO0 ) > 0){// 从Rx FIFO 0中读取消�?if(HAL_FDCAN_GetRxMessage(&hfdcan1,FDCAN_RX_FIFO0 ,&pHeader,pData)== HAL_OK){TxData[4]=pHeader.RxTimestamp & 0xFF;TxData[5]=pHeader.DataLength & 0xFF;TxData[6]=pHeader.Identifier & 0xFF;TxData[7]=pData[0];counter++;CAN_Send();}else{// 处理读取消息时的错误Error_Handler();}}// 清除Rx FIFO 0新消息标志__HAL_FDCAN_CLEAR_FLAG(&hfdcan1, FDCAN_FLAG_RX_FIFO0_NEW_MESSAGE);}
}

如果检测到FIFO0新消息标志：FDCAN_FLAG_RX_FIFO0_NEW_MESSAGE
则循环处理FIFO0中的消息