代码收藏家 STM32 G431与H743实现CAN-FD通信的细节解析与比较
STM32相同型号实现CAN通信相对比较容易，只需要参数完全一致，比特率不超出CAN模块的范围，一般就能够实现通信。但G431和H743的时钟不一样，需要配置参数使比特率完全相等。CAN通信分为仲裁阶段和数据阶段，仲裁阶段波特率不超过1M，数据阶段波特率一般不超过8M。对于仲裁阶段和数据阶段，波特率的计算都遵循以下公式：
波特率=FDCAN时钟频率/(预分频器×(TimeSeg1+TimeSeg2+1))
数据采样点最好在75%~80%范围内，数据采样点的计算公式：
采样点 = TimeSeg1 / ( TimeSeg1+TimeSeg2+1 )
G431
对于G431，FDCAN所在的时钟树为170M：
仲裁阶段配置：
hfdcan1.Init.NominalPrescaler = 17;
hfdcan1.Init.NominalSyncJumpWidth = 2;
hfdcan1.Init.NominalTimeSeg1 = 7;
hfdcan1.Init.NominalTimeSeg2 = 2;波特率 = 170M/(NominalPrescaler*(1+NominalTimeSeg1+NominalTimeSeg2)) = 1M
采样点 = TimeSeg1 / ( TimeSeg1+TimeSeg2+1 ) = 7/ 10 = 70%
数据阶段配置：
hfdcan1.Init.DataPrescaler = 2;
hfdcan1.Init.DataSyncJumpWidth = 2;
hfdcan1.Init.DataTimeSeg1 = 13;
hfdcan1.Init.DataTimeSeg2 = 3;波特率 = 170M/(DataPrescaler*(1+DataTimeSeg1+DataTimeSeg2)) = 5M
采样点 = TimeSeg1 / ( TimeSeg1+TimeSeg2+1 ) = 13 / 17 = 76.47%
完整代码如下：
void MX_FDCAN1_Init(void)
{
/* USER CODE BEGIN FDCAN1_Init 0 */
/* 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_DIV1;
hfdcan1.Init.FrameFormat = FDCAN_FRAME_FD_BRS;
hfdcan1.Init.Mode = FDCAN_MODE_NORMAL;
hfdcan1.Init.AutoRetransmission = DISABLE;
hfdcan1.Init.TransmitPause = DISABLE;
hfdcan1.Init.ProtocolException = DISABLE;
hfdcan1.Init.NominalPrescaler = 17;
hfdcan1.Init.NominalSyncJumpWidth = 2;
hfdcan1.Init.NominalTimeSeg1 = 7;
hfdcan1.Init.NominalTimeSeg2 = 2;
hfdcan1.Init.DataPrescaler = 2;
hfdcan1.Init.DataSyncJumpWidth = 2;
hfdcan1.Init.DataTimeSeg1 = 13;
hfdcan1.Init.DataTimeSeg2 = 3;
hfdcan1.Init.StdFiltersNbr = 1;
hfdcan1.Init.ExtFiltersNbr = 1;
hfdcan1.Init.TxFifoQueueMode = FDCAN_TX_FIFO_OPERATION;
if (HAL_FDCAN_Init(&hfdcan1) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN FDCAN1_Init 2 */
// 配置接收所有标准 ID 的过滤器
FDCAN_FilterTypeDef sFilterConfig;
sFilterConfig.IdType = FDCAN_STANDARD_ID;
sFilterConfig.FilterIndex = 0;
sFilterConfig.FilterType = FDCAN_FILTER_MASK;
sFilterConfig.FilterConfig = FDCAN_FILTER_TO_RXFIFO0;
sFilterConfig.FilterID1 = 0x001; // 过滤器ID
sFilterConfig.FilterID2 = 0x7FF; // 过滤器掩码，0x000表示接收所有ID
if (HAL_FDCAN_ConfigFilter(&hfdcan1, &sFilterConfig) != HAL_OK)
{
Error_Handler();
}
if (HAL_FDCAN_ConfigGlobalFilter(&hfdcan1, FDCAN_REJECT, FDCAN_REJECT, FDCAN_FILTER_REMOTE, FDCAN_FILTER_REMOTE) != HAL_OK)
{
Error_Handler();
}
// 激活通知
if (HAL_FDCAN_ActivateNotification(&hfdcan1, FDCAN_IT_RX_FIFO0_NEW_MESSAGE, 0) != HAL_OK)
{
Error_Handler();
}
// 启动FDCAN模块
if (HAL_FDCAN_Start(&hfdcan1) != HAL_OK)
{
Error_Handler();
}
/* USER CODE END FDCAN1_Init 2 */
}
void HAL_FDCAN_MspInit(FDCAN_HandleTypeDef* fdcanHandle)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
RCC_PeriphCLKInitTypeDef PeriphClkInit = {0};
if(fdcanHandle->Instance==FDCAN1)
{
/* USER CODE BEGIN FDCAN1_MspInit 0 */
/* USER CODE END FDCAN1_MspInit 0 */
/** Initializes the peripherals clocks
*/
PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_FDCAN;
PeriphClkInit.FdcanClockSelection = RCC_FDCANCLKSOURCE_PCLK1;
if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
{
Error_Handler();
}
/* FDCAN1 clock enable */
__HAL_RCC_FDCAN_CLK_ENABLE();
__HAL_RCC_GPIOA_CLK_ENABLE();
/**FDCAN1 GPIO Configuration
PA11 ------> FDCAN1_RX
PA12 ------> FDCAN1_TX
*/
GPIO_InitStruct.Pin = GPIO_PIN_11|GPIO_PIN_12;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
GPIO_InitStruct.Alternate = GPIO_AF9_FDCAN1;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
/* FDCAN1 interrupt Init */
HAL_NVIC_SetPriority(FDCAN1_IT0_IRQn, 5, 0);
HAL_NVIC_EnableIRQ(FDCAN1_IT0_IRQn);
HAL_NVIC_SetPriority(FDCAN1_IT1_IRQn, 5, 0);
HAL_NVIC_EnableIRQ(FDCAN1_IT1_IRQn);
/* USER CODE BEGIN FDCAN1_MspInit 1 */
/* USER CODE END FDCAN1_MspInit 1 */
}
}
void HAL_FDCAN_MspDeInit(FDCAN_HandleTypeDef* fdcanHandle)
{
if(fdcanHandle->Instance==FDCAN1)
{
/* USER CODE BEGIN FDCAN1_MspDeInit 0 */
/* USER CODE END FDCAN1_MspDeInit 0 */
/* Peripheral clock disable */
__HAL_RCC_FDCAN_CLK_DISABLE();
/**FDCAN1 GPIO Configuration
PA11 ------> FDCAN1_RX
PA12 ------> FDCAN1_TX
*/
HAL_GPIO_DeInit(GPIOA, GPIO_PIN_11|GPIO_PIN_12);
/* FDCAN1 interrupt Deinit */
HAL_NVIC_DisableIRQ(FDCAN1_IT0_IRQn);
HAL_NVIC_DisableIRQ(FDCAN1_IT1_IRQn);
/* USER CODE BEGIN FDCAN1_MspDeInit 1 */
/* USER CODE END FDCAN1_MspDeInit 1 */
}
}
/* USER CODE BEGIN 1 */
void HAL_FDCAN_RxFifo0Callback(FDCAN_HandleTypeDef *hfdcan, uint32_t RxFifo0ITs)
{
if ((RxFifo0ITs & FDCAN_IT_RX_FIFO0_NEW_MESSAGE) != RESET)
{
FDCAN_ReceiveData();
}
}
// 发送数据示例
void FDCAN_SendData(uint32_t id, uint8_t *data, uint8_t length)
{
FDCAN_TxHeaderTypeDef TxHeader;
TxHeader.Identifier = id;
TxHeader.IdType = FDCAN_STANDARD_ID; // 使用标准ID
TxHeader.TxFrameType = FDCAN_DATA_FRAME;
TxHeader.DataLength = length; // 数据长度，单位为字节
TxHeader.ErrorStateIndicator = FDCAN_ESI_ACTIVE;
TxHeader.BitRateSwitch = FDCAN_BRS_ON;
TxHeader.FDFormat = FDCAN_FD_CAN;
TxHeader.TxEventFifoControl = FDCAN_NO_TX_EVENTS;
TxHeader.MessageMarker = 0;
if ((hfdcan1.Instance->TXFQS & FDCAN_TXFQS_TFQF) != 0)
{
// 发送队列已满，等待或处理
printf("Transmit FIFO is full\n");
return;
}
if (HAL_FDCAN_AddMessageToTxFifoQ(&hfdcan1, &TxHeader, data) != HAL_OK)
{
// 处理发送错误
printf("Error sending message\n");
Error_Handler();
}
}H743
FDCAN时钟树为120M：
计算方法和G431相同，直接给出完整代码：
void MX_FDCAN1_Init(void)
{
/* USER CODE BEGIN FDCAN1_Init 0 */
/* USER CODE END FDCAN1_Init 0 */
/* USER CODE BEGIN FDCAN1_Init 1 */
/* USER CODE END FDCAN1_Init 1 */
hfdcan1.Instance = FDCAN1;
hfdcan1.Init.FrameFormat = FDCAN_FRAME_FD_BRS;
hfdcan1.Init.Mode = FDCAN_MODE_NORMAL;
hfdcan1.Init.AutoRetransmission = DISABLE;
hfdcan1.Init.TransmitPause = DISABLE;
hfdcan1.Init.ProtocolException = DISABLE;
hfdcan1.Init.NominalPrescaler = 12;
hfdcan1.Init.NominalSyncJumpWidth = 2;
hfdcan1.Init.NominalTimeSeg1 = 7;
hfdcan1.Init.NominalTimeSeg2 = 2;
hfdcan1.Init.DataPrescaler = 2;
hfdcan1.Init.DataSyncJumpWidth = 2;
hfdcan1.Init.DataTimeSeg1 = 9;
hfdcan1.Init.DataTimeSeg2 = 2;
hfdcan1.Init.MessageRAMOffset = 0;
hfdcan1.Init.StdFiltersNbr = 1;
hfdcan1.Init.ExtFiltersNbr = 1;
hfdcan1.Init.RxFifo0ElmtsNbr = 1;
hfdcan1.Init.RxFifo0ElmtSize = FDCAN_DATA_BYTES_64;
hfdcan1.Init.RxFifo1ElmtsNbr = 1;
hfdcan1.Init.RxFifo1ElmtSize = FDCAN_DATA_BYTES_64;
hfdcan1.Init.RxBuffersNbr = 1;
hfdcan1.Init.RxBufferSize = FDCAN_DATA_BYTES_64;
hfdcan1.Init.TxEventsNbr = 0;
hfdcan1.Init.TxBuffersNbr = 1;
hfdcan1.Init.TxFifoQueueElmtsNbr = 1;
hfdcan1.Init.TxFifoQueueMode = FDCAN_TX_FIFO_OPERATION;
hfdcan1.Init.TxElmtSize = FDCAN_DATA_BYTES_64;
if (HAL_FDCAN_Init(&hfdcan1) != HAL_OK)
{
g_Error = ERROR_FDCAN_INIT;
Error_Handler();
}
/* USER CODE BEGIN FDCAN1_Init 2 */
// ???????? ID ????
FDCAN_FilterTypeDef sFilterConfig;
sFilterConfig.IdType = FDCAN_STANDARD_ID;
sFilterConfig.FilterIndex = 0;
sFilterConfig.FilterType = FDCAN_FILTER_MASK;
sFilterConfig.FilterConfig = FDCAN_FILTER_TO_RXFIFO0;
sFilterConfig.FilterID1 = 0x100; // ???ID
sFilterConfig.FilterID2 = 0x1F0; // ?????,0x000??????ID
if (HAL_FDCAN_ConfigFilter(&hfdcan1, &sFilterConfig) != HAL_OK)
{
g_Error = ERROR_FDCAN_CONFIG_FILTER;
Error_Handler();
}
if (HAL_FDCAN_ConfigGlobalFilter(&hfdcan1, FDCAN_REJECT, FDCAN_REJECT, FDCAN_FILTER_REMOTE, FDCAN_FILTER_REMOTE) != HAL_OK)
{
g_Error = ERROR_FDCAN_CONFIG_GLOBAL_FILTER;
Error_Handler();
}
// ????
if (HAL_FDCAN_ActivateNotification(&hfdcan1, FDCAN_IT_RX_FIFO0_NEW_MESSAGE, 0) != HAL_OK)
{
g_Error = ERROR_FDCAN_ACTIVATE_NOTIFICATION;
Error_Handler();
}
// ??FDCAN??
if (HAL_FDCAN_Start(&hfdcan1) != HAL_OK)
{
g_Error = ERROR_FDCAN_START;
Error_Handler();
}
/* USER CODE END FDCAN1_Init 2 */
}
void HAL_FDCAN_MspInit(FDCAN_HandleTypeDef* fdcanHandle)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
RCC_PeriphCLKInitTypeDef PeriphClkInitStruct = {0};
if(fdcanHandle->Instance==FDCAN1)
{
/* USER CODE BEGIN FDCAN1_MspInit 0 */
/* USER CODE END FDCAN1_MspInit 0 */
/** Initializes the peripherals clock
*/
PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_FDCAN;
PeriphClkInitStruct.FdcanClockSelection = RCC_FDCANCLKSOURCE_PLL;
if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK)
{
Error_Handler();
}
/* FDCAN1 clock enable */
__HAL_RCC_FDCAN_CLK_ENABLE();
__HAL_RCC_GPIOD_CLK_ENABLE();
/**FDCAN1 GPIO Configuration
PD0 ------> FDCAN1_RX
PD1 ------> FDCAN1_TX
*/
GPIO_InitStruct.Pin = GPIO_PIN_0|GPIO_PIN_1;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
GPIO_InitStruct.Alternate = GPIO_AF9_FDCAN1;
HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);
/* FDCAN1 interrupt Init */
HAL_NVIC_SetPriority(FDCAN1_IT0_IRQn, 5, 0);
HAL_NVIC_EnableIRQ(FDCAN1_IT0_IRQn);
HAL_NVIC_SetPriority(FDCAN1_IT1_IRQn, 5, 0);
HAL_NVIC_EnableIRQ(FDCAN1_IT1_IRQn);
HAL_NVIC_SetPriority(FDCAN_CAL_IRQn, 5, 0);
HAL_NVIC_EnableIRQ(FDCAN_CAL_IRQn);
/* USER CODE BEGIN FDCAN1_MspInit 1 */
/* USER CODE END FDCAN1_MspInit 1 */
}
}
void HAL_FDCAN_MspDeInit(FDCAN_HandleTypeDef* fdcanHandle)
{
if(fdcanHandle->Instance==FDCAN1)
{
/* USER CODE BEGIN FDCAN1_MspDeInit 0 */
/* USER CODE END FDCAN1_MspDeInit 0 */
/* Peripheral clock disable */
__HAL_RCC_FDCAN_CLK_DISABLE();
/**FDCAN1 GPIO Configuration
PD0 ------> FDCAN1_RX
PD1 ------> FDCAN1_TX
*/
HAL_GPIO_DeInit(GPIOD, GPIO_PIN_0|GPIO_PIN_1);
/* FDCAN1 interrupt Deinit */
HAL_NVIC_DisableIRQ(FDCAN1_IT0_IRQn);
HAL_NVIC_DisableIRQ(FDCAN1_IT1_IRQn);
HAL_NVIC_DisableIRQ(FDCAN_CAL_IRQn);
/* USER CODE BEGIN FDCAN1_MspDeInit 1 */
/* USER CODE END FDCAN1_MspDeInit 1 */
}
}
/* USER CODE BEGIN 1 */
void HAL_FDCAN_RxFifo0Callback(FDCAN_HandleTypeDef *hfdcan, uint32_t RxFifo0ITs)
{
if ((RxFifo0ITs & FDCAN_IT_RX_FIFO0_NEW_MESSAGE) != RESET)
{
FDCAN_ReceiveData();
}
}
void FDCAN_ReceiveData(void)
{
FDCAN_MessageTypeDef message;
if (HAL_FDCAN_GetRxMessage(&hfdcan1, FDCAN_RX_FIFO0, &message.RxHeader, message.RxData) == HAL_OK)
{
// printf("Received message ID: 0x%03X\n", RxHeader.Identifier);
// printf("Received data: ");
// for (int i = 0; i < (RxHeader.DataLength); i++)
// {
// printf("0x%02X ", RxData[i]);
// }
// printf("\n");
// 将消息放入队列
if (fdcanQueue != NULL && allServiceIsStart)
{
BaseType_t xHigherPriorityTaskWoken = pdTRUE;
if (xQueueSendFromISR(fdcanQueue, &message, &xHigherPriorityTaskWoken) != pdPASS)
{
g_Error = ERROR_QUEUE_SEND;
Error_Handler();
}
}
}
else
{
g_Error = ERROR_FDCAN_RECEIVE;
Error_Handler();
}
}
// ??????
void FDCAN_SendData(uint32_t id, uint8_t *data, uint8_t length)
{
FDCAN_TxHeaderTypeDef TxHeader;
TxHeader.Identifier = id;
TxHeader.IdType = FDCAN_STANDARD_ID; // ????ID
TxHeader.TxFrameType = FDCAN_DATA_FRAME;
// TxHeader.DataLength = length; // ????,?????
TxHeader.DataLength = length;
TxHeader.ErrorStateIndicator = FDCAN_ESI_ACTIVE;
TxHeader.BitRateSwitch = FDCAN_BRS_ON;
TxHeader.FDFormat = FDCAN_FD_CAN;
TxHeader.TxEventFifoControl = FDCAN_NO_TX_EVENTS;
TxHeader.MessageMarker = 0;
if ((hfdcan1.Instance->TXFQS & FDCAN_TXFQS_TFQF) != 0)
{
// ??????,?????
osDelay(10); // FIFO 满了延迟10ms
printf("Transmit FIFO is full\n");
return;
}
if (HAL_FDCAN_AddMessageToTxFifoQ(&hfdcan1, &TxHeader, data) != HAL_OK)
{
g_Error = ERROR_FDCAN_SEND;
Error_Handler();
}
}
经过测试，H743 + 三块G431可以通过CAN-FD实现正常通信。
作者：不再犹豫123
