STM32CubeMXcan通讯教程

STM32CubeMX是ST官方推出的一款图形化配置工具，可以帮助开发者快速配置STM32系列单片机的引脚、时钟、外设等，同时也可以生成基于HAL库的初始化代码。对于CAN通讯的配置，可以按照以下步骤进行：

1. 打开STM32CubeMX工具，选择对应的芯片型号。

2. 在Pinout & Configuration选项卡中，选择CAN1或CAN2外设，然后在右侧的配置面板中进行引脚配置，包括RX和TX引脚的选择、模式配置等。

3. 在Configuration选项卡中，选择CAN外设，然后在右侧的配置面板中进行相应的配置，包括波特率、传输模式、过滤器等。

4. 生成代码并导入到IDE中，然后在代码中调用HAL库提供的相关CAN API函数，进行CAN通讯的初始化和数据收发操作。

以下是一个简单的CAN通讯发送数据的代码示例：

#include "stm32f4xx_hal.h"

CAN_HandleTypeDef hcan;

void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_CAN1_Init(void);

int main(void)
{
  HAL_Init();
  SystemClock_Config();
  MX_GPIO_Init();
  MX_CAN1_Init();

  CAN_TxHeaderTypeDef TxHeader;
  uint32_t TxMailbox;
  uint8_t TxData[8] = {0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08};
  TxHeader.StdId = 0x123;
  TxHeader.ExtId = 0;
  TxHeader.RTR = CAN_RTR_DATA;
  TxHeader.IDE = CAN_ID_STD;
  TxHeader.DLC = 8;
  TxHeader.TransmitGlobalTime = DISABLE;

  while (1)
  {
    if (HAL_CAN_GetTxMailboxesFreeLevel(&hcan) != 0)
    {
      HAL_CAN_AddTxMessage(&hcan, &TxHeader, TxData, &TxMailbox);
      break;
    }
  }

  while (1)
  {
  }
}

void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct;
  RCC_ClkInitTypeDef RCC_ClkInitStruct;

  __HAL_RCC_PWR_CLK_ENABLE();
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);

  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
  RCC_OscInitStruct.PLL.PLLM = 8;
  RCC_OscInitStruct.PLL.PLLN = 168;
  RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
  RCC_OscInitStruct.PLL.PLLQ = 4;
  HAL_RCC_OscConfig(&RCC_OscInitStruct);

  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_SYSCLK
                                | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV4;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;
  HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_5);
}

static void MX_CAN1_Init(void)
{
  hcan.Instance = CAN1;
  hcan.Init.Prescaler = 4;
  hcan.Init.Mode = CAN_MODE_NORMAL;
  hcan.Init.SyncJumpWidth = CAN_SJW_1TQ;
  hcan.Init.TimeSeg1 = CAN_BS1_8TQ;
  hcan.Init.TimeSeg2 = CAN_BS2_3TQ;
  hcan.Init.TimeTriggeredMode = DISABLE;
  hcan.Init.AutoBusOff = DISABLE;
  hcan.Init.AutoWakeUp = DISABLE;
  hcan.Init.AutoRetransmission = ENABLE;
  hcan.Init.ReceiveFifoLocked = DISABLE;
  hcan.Init.TransmitFifoPriority = ENABLE;
  if (HAL_CAN_Init(&hcan) != HAL_OK)
  {
    _Error_Handler(__FILE__, __LINE__);
  }

  CAN_FilterTypeDef sFilterConfig;
  sFilterConfig.FilterBank = 0;
  sFilterConfig.FilterMode = CAN_FILTERMODE_IDMASK;
  sFilterConfig.FilterScale = CAN_FILTERSCALE_32BIT;
  sFilterConfig.FilterIdHigh = 0x0000;
  sFilterConfig.FilterIdLow = 0x0000;
  sFilterConfig.FilterMaskIdHigh = 0x0000;
  sFilterConfig.FilterMaskIdLow = 0x0000;
  sFilterConfig.FilterFIFOAssignment = 0;
  sFilterConfig.FilterActivation = ENABLE;
  sFilterConfig.SlaveStartFilterBank = 14;
  if (HAL_CAN_ConfigFilter(&hcan, &sFilterConfig) != HAL_OK)
  {
    _Error_Handler(__FILE__, __LINE__);
  }
}

static void MX_GPIO_Init(void)
{
  GPIO_InitTypeDef GPIO_InitStruct;

  __HAL_RCC_GPIOA_CLK_ENABLE();

  GPIO_InitStruct.Pin = GPIO_PIN_12 | GPIO_PIN_11;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
  GPIO_InitStruct.Alternate = GPIO_AF9_CAN1;
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
}

以上代码初始化了CAN1外设，并发送了一个标准ID为0x123，数据为8个字节的CAN数据帧。