STM32can通讯教程

以下是基于HAL库的STM32 CAN通讯教程：

1. 配置CAN硬件

首先，需要在STM32的CubeMX中配置CAN硬件，包括引脚、时钟等参数。在配置时，需要设置CAN的工作模式、波特率等参数。一般情况下，可以选择普通CAN模式，然后设置波特率为500Kbps。

2. 配置CAN软件

在软件中，需要使用STM32 HAL库提供的函数来实现CAN通讯。在使用之前，需要在代码中引入相应的头文件，并初始化CAN接口。

#include "stm32f4xx_hal.h"

/* 初始化CAN */
CAN_HandleTypeDef hcan1;
CAN_FilterTypeDef filter;

void can1_init(void)
{
    hcan1.Instance = CAN1;
    hcan1.Init.Prescaler = 4;
    hcan1.Init.Mode = CAN_MODE_NORMAL;
    hcan1.Init.SyncJumpWidth = CAN_SJW_1TQ;
    hcan1.Init.TimeSeg1 = CAN_BS1_13TQ;
    hcan1.Init.TimeSeg2 = CAN_BS2_2TQ;
    hcan1.Init.TimeTriggeredMode = DISABLE;
    hcan1.Init.AutoBusOff = DISABLE;
    hcan1.Init.AutoWakeUp = DISABLE;
    hcan1.Init.AutoRetransmission = ENABLE;
    hcan1.Init.ReceiveFifoLocked = DISABLE;
    hcan1.Init.TransmitFifoPriority = DISABLE;
    HAL_CAN_Init(&hcan1);

    /* 配置CAN过滤器 */
    filter.FilterBank = 0;
    filter.FilterMode = CAN_FILTERMODE_IDMASK;
    filter.FilterScale = CAN_FILTERSCALE_32BIT;
    filter.FilterIdHigh = 0x0000;
    filter.FilterIdLow = 0x0000;
    filter.FilterMaskIdHigh = 0x0000;
    filter.FilterMaskIdLow = 0x0000;
    filter.FilterFIFOAssignment = CAN_FILTER_FIFO0;
    filter.FilterActivation = ENABLE;
    HAL_CAN_ConfigFilter(&hcan1, &filter);
}

3. 发送CAN数据帧

通过调用HAL库提供的函数，可以方便地实现CAN数据帧的发送。在发送前，需要设置CAN的标识符、数据长度和数据内容等参数。以下是一个简单的CAN数据帧发送函数。

void can1_send(uint32_t id, uint8_t* data, uint8_t len)
{
    CAN_TxHeaderTypeDef tx_header;
    uint32_t tx_mailbox;

    tx_header.StdId = id;
    tx_header.IDE = CAN_ID_STD;
    tx_header.RTR = CAN_RTR_DATA;
    tx_header.DLC = len;
    HAL_CAN_AddTxMessage(&hcan1, &tx_header, data, &tx_mailbox);
}

4. 接收CAN数据帧

通过调用HAL库提供的函数，可以方便地实现CAN数据帧的接收。在接收时，需要设置CAN的过滤器和接收缓冲区等参数。以下是一个简单的CAN数据帧接收函数。

void can1_receive(uint32_t* id, uint8_t* data, uint8_t* len)
{
    CAN_RxHeaderTypeDef rx_header;

    HAL_CAN_GetRxMessage(&hcan1, CAN_FILTER_FIFO0, &rx_header, data);
    *id = rx_header.StdId;
    *len = rx_header.DLC;
}

5. 示例代码

#include "stm32f4xx_hal.h"

/* 初始化CAN */
CAN_HandleTypeDef hcan1;
CAN_FilterTypeDef filter;

void can1_init(void)
{
    hcan1.Instance = CAN1;
    hcan1.Init.Prescaler = 4;
    hcan1.Init.Mode = CAN_MODE_NORMAL;
    hcan1.Init.SyncJumpWidth = CAN_SJW_1TQ;
    hcan1.Init.TimeSeg1 = CAN_BS1_13TQ;
    hcan1.Init.TimeSeg2 = CAN_BS2_2TQ;
    hcan1.Init.TimeTriggeredMode = DISABLE;
    hcan1.Init.AutoBusOff = DISABLE;
    hcan1.Init.AutoWakeUp = DISABLE;
    hcan1.Init.AutoRetransmission = ENABLE;
    hcan1.Init.ReceiveFifoLocked = DISABLE;
    hcan1.Init.TransmitFifoPriority = DISABLE;
    HAL_CAN_Init(&hcan1);

    /* 配置CAN过滤器 */
    filter.FilterBank = 0;
    filter.FilterMode = CAN_FILTERMODE_IDMASK;
    filter.FilterScale = CAN_FILTERSCALE_32BIT;
    filter.FilterIdHigh = 0x0000;
    filter.FilterIdLow = 0x0000;
    filter.FilterMaskIdHigh = 0x0000;
    filter.FilterMaskIdLow = 0x0000;
    filter.FilterFIFOAssignment = CAN_FILTER_FIFO0;
    filter.FilterActivation = ENABLE;
    HAL_CAN_ConfigFilter(&hcan1, &filter);
}

/* 发送CAN数据帧 */
void can1_send(uint32_t id, uint8_t* data, uint8_t len)
{
    CAN_TxHeaderTypeDef tx_header;
    uint32_t tx_mailbox;

    tx_header.StdId = id;
    tx_header.IDE = CAN_ID_STD;
    tx_header.RTR = CAN_RTR_DATA;
    tx_header.DLC = len;
    HAL_CAN_AddTxMessage(&hcan1, &tx_header, data, &tx_mailbox);
}

/* 接收CAN数据帧 */
void can1_receive(uint32_t* id, uint8_t* data, uint8_t* len)
{
    CAN_RxHeaderTypeDef rx_header;

    HAL_CAN_GetRxMessage(&hcan1, CAN_FILTER_FIFO0, &rx_header, data);
    *id = rx_header.StdId;
    *len = rx_header.DLC;
}

int main(void)
{
    uint32_t id;
    uint8_t data[8];
    uint8_t len;

    HAL_Init();
    can1_init();

    while (1)
    {
        /* 接收CAN数据 */
        can1_receive(&id, data, &len);

        /* 处理CAN数据 */
        // do something...
    }
}

以上就是基于HAL库的STM32 CAN通讯教程。注意，以上代码仅供参考，具体实现需要根据实际情况进行修改。