STM32F103使用CAN通信读取多个扩展帧命令,运用switch语句，并将命令进行解析

以下是一个使用STM32F103的CAN通信读取多个扩展帧命令并解析的示例代码：

#include "stm32f10x.h"
#include "stm32f10x_can.h"

#define COMMAND1_ID 0x12345678
#define COMMAND2_ID 0x87654321
#define COMMAND3_ID 0x11111111

void CAN_Config(void);
void CAN_NVIC_Config(void);
void CAN1_RX0_IRQHandler(void);

CanRxMsg RxMessage;

int main(void)
{
    CAN_Config();
    CAN_NVIC_Config();

    while(1)
    {
        // Wait for a CAN message to be received
    }
}

void CAN_Config(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    CAN_InitTypeDef CAN_InitStructure;
    CAN_FilterInitTypeDef CAN_FilterInitStructure;

    // Enable the CAN and GPIO clocks
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO | RCC_APB2Periph_GPIOB | RCC_APB2Periph_GPIOC | RCC_APB2Periph_GPIOD | RCC_APB2Periph_CAN1, ENABLE);

    // Configure the CAN RX pin
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
    GPIO_Init(GPIOB, &GPIO_InitStructure);

    // Configure the CAN TX pin
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOB, &GPIO_InitStructure);

    // Configure the CAN peripheral
    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_8tq;
    CAN_InitStructure.CAN_BS2 = CAN_BS2_7tq;
    CAN_InitStructure.CAN_Prescaler = 2;
    CAN_Init(CAN1, &CAN_InitStructure);

    // Configure the CAN filter
    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 the CAN RX interrupt
    CAN_ITConfig(CAN1, CAN_IT_FMP0, ENABLE);
}

void CAN_NVIC_Config(void)
{
    NVIC_InitTypeDef NVIC_InitStructure;

    NVIC_PriorityGroupConfig(NVIC_PriorityGroup_0);

    NVIC_InitStructure.NVIC_IRQChannel = USB_LP_CAN1_RX0_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
}

void CAN1_RX0_IRQHandler(void)
{
    if(CAN_GetITStatus(CAN1, CAN_IT_FMP0) != RESET)
    {
        CAN_Receive(CAN1, CAN_FIFO0, &RxMessage);

        switch(RxMessage.ExtId)
        {
            case COMMAND1_ID:
                // Do something for command 1
                break;

            case COMMAND2_ID:
                // Do something for command 2
                break;

            case COMMAND3_ID:
                // Do something for command 3
                break;

            default:
                break;
        }
    }
}

在上述代码中，我们使用了STM32F103的CAN1接口来进行CAN通信。首先，我们在`CAN_Config()`函数中对CAN接口进行了初始化和过滤器的配置。然后，我们在`CAN_NVIC_Config()`函数中对CAN RX中断进行了配置。在主循环中，我们等待CAN消息的接收。当接收到CAN消息时，我们在`CAN1_RX0_IRQHandler()`函数中使用`switch`语句对不同的扩展帧命令进行解析。如果收到了未知的命令，则不会执行任何操作。注意，如果使用了其他的CAN接口，一些参数（比如GPIO端口和NVIC通道）需要进行相应的更改。