STM32 CAN 驱动程序

以下是一个简单的 STM32 CAN 驱动程序的示例，可以用于启用 CAN 总线并发送和接收 CAN 消息。注意，这个程序假设你已经在 STM32 上启用了 CAN 总线，并且已经配置了 CAN 控制器的时序和位宽等参数。

#include "stm32f4xx.h"

CAN_InitTypeDef        CAN_InitStructure;
CAN_FilterInitTypeDef  CAN_FilterInitStructure;
CanTxMsg                TxMessage;
CanRxMsg                RxMessage;

void CAN_Config(void)
{
  /* CAN Periph clock enable */
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1, ENABLE);

  /* CAN1 Reset */
  CAN_DeInit(CAN1);

  /* CAN1 Init */
  CAN_InitStructure.CAN_TTCM = DISABLE;
  CAN_InitStructure.CAN_ABOM = DISABLE;
  CAN_InitStructure.CAN_AWUM = DISABLE;
  CAN_InitStructure.CAN_NART = DISABLE;
  CAN_InitStructure.CAN_RFLM = DISABLE;
  CAN_InitStructure.CAN_TXFP = DISABLE;
  CAN_InitStructure.CAN_Mode = CAN_Mode_Normal;
  CAN_InitStructure.CAN_SJW = CAN_SJW_1tq;
  CAN_InitStructure.CAN_BS1 = CAN_BS1_9tq;
  CAN_InitStructure.CAN_BS2 = CAN_BS2_4tq;
  CAN_InitStructure.CAN_Prescaler = 4;
  CAN_Init(CAN1, &CAN_InitStructure);

  /* CAN filter init */
  CAN_FilterInitStructure.CAN_FilterNumber = 0;
  CAN_FilterInitStructure.CAN_FilterMode = CAN_FilterMode_IdMask;
  CAN_FilterInitStructure.CAN_FilterScale = CAN_FilterScale_32bit;
  CAN_FilterInitStructure.CAN_FilterIdHigh = 0x0000;
  CAN_FilterInitStructure.CAN_FilterIdLow = 0x0000;
  CAN_FilterInitStructure.CAN_FilterMaskIdHigh = 0x0000;
  CAN_FilterInitStructure.CAN_FilterMaskIdLow = 0x0000;
  CAN_FilterInitStructure.CAN_FilterFIFOAssignment = 0;
  CAN_FilterInitStructure.CAN_FilterActivation = ENABLE;
  CAN_FilterInit(&CAN_FilterInitStructure);

  /* Enable FIFO 0 message pending Interrupt */
  CAN_ITConfig(CAN1, CAN_IT_FMP0, ENABLE);
}

void CAN_SendMsg(void)
{
  /* Transmit */
  TxMessage.StdId = 0x321;
  TxMessage.RTR = CAN_RTR_DATA;
  TxMessage.IDE = CAN_ID_STD;
  TxMessage.DLC = 2;
  TxMessage.Data[0] = 0xCA;
  TxMessage.Data[1] = 0xFE;
  CAN_Transmit(CAN1, &TxMessage);
}

void CAN_ReceiveMsg(void)
{
  /* Receive */
  while(CAN_MessagePending(CAN1, CAN_FIFO0) == 0);
  CAN_Receive(CAN1, CAN_FIFO0, &RxMessage);
}

void CAN1_RX0_IRQHandler(void)
{
  if (CAN_GetITStatus(CAN1, CAN_IT_FMP0) != RESET)
  {
    CAN_ReceiveMsg();
    CAN_ClearITPendingBit(CAN1, CAN_IT_FMP0);
  }
}

int main(void)
{
  /* CAN Configuration */
  CAN_Config();

  /* Send Message */
  CAN_SendMsg();

  while (1)
  {
    /* Wait for reception of message */
    if (CAN_MessagePending(CAN1, CAN_FIFO0) != 0)
    {
      /* Receive message */
      CAN_ReceiveMsg();
    }
  }
}

该程序通过 `CAN_Config` 函数初始化 CAN 控制器和 CAN 滤波器，并通过 `CAN_SendMsg` 函数发送一个 CAN 消息。在主循环中，程序将等待接收 CAN 消息，并在接收到消息后调用 `CAN_ReceiveMsg` 函数进行处理。在 `CAN1_RX0_IRQHandler` 中断处理程序中，程序将检查是否有 CAN 消息待处理，并在接收到消息后调用 `CAN_ReceiveMsg` 函数进行处理。