求助：使用野火骄阳开发板rt-thread 4.1.0，使用官方can例程 write 返回值一直为0

发布于 2023-05-26 00:02:17 浏览：518 订阅该版

**一、can驱动配置**
**	1、使用rt-thread setting打开can

2、使用stm32cube配置can引脚 ****

```c
/**
* @brief CAN MSP Initialization
* This function configures the hardware resources used in this example
* @param hcan: CAN handle pointer
* @retval None
*/
void HAL_CAN_MspInit(CAN_HandleTypeDef* hcan)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};
  if(hcan->Instance==CAN1)
  {
  /* USER CODE BEGIN CAN1_MspInit 0 */

/* USER CODE END CAN1_MspInit 0 */
    /* Peripheral clock enable */
    __HAL_RCC_CAN1_CLK_ENABLE();

__HAL_RCC_GPIOI_CLK_ENABLE();
    __HAL_RCC_GPIOB_CLK_ENABLE();
    /**CAN1 GPIO Configuration
    PI9     ------> CAN1_RX
    PB9     ------> CAN1_TX
    */
    GPIO_InitStruct.Pin = GPIO_PIN_9;
    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(GPIOI, &GPIO_InitStruct);

GPIO_InitStruct.Pin = GPIO_PIN_9;
    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(GPIOB, &GPIO_InitStruct);

/* USER CODE BEGIN CAN1_MspInit 1 */

/* USER CODE END CAN1_MspInit 1 */
  }

}

/**
* @brief CAN MSP De-Initialization
* This function freeze the hardware resources used in this example
* @param hcan: CAN handle pointer
* @retval None
*/
void HAL_CAN_MspDeInit(CAN_HandleTypeDef* hcan)
{
  if(hcan->Instance==CAN1)
  {
  /* USER CODE BEGIN CAN1_MspDeInit 0 */

/* USER CODE END CAN1_MspDeInit 0 */
    /* Peripheral clock disable */
    __HAL_RCC_CAN1_CLK_DISABLE();

/**CAN1 GPIO Configuration
    PI9     ------> CAN1_RX
    PB9     ------> CAN1_TX
    */
    HAL_GPIO_DeInit(GPIOI, GPIO_PIN_9);

HAL_GPIO_DeInit(GPIOB, GPIO_PIN_9);

/* USER CODE BEGIN CAN1_MspDeInit 1 */

/* USER CODE END CAN1_MspDeInit 1 */
  }

}

```
** 3、board.h添加**
    #define BSP_USING_CAN
    #define BSP_USING_CAN1
** 4、打开**
    #define HAL_CAN_MODULE_ENABLED
** 5、时钟配置**
 
```c

void system_clock_config(int target_freq_mhz)
{
    RCC_OscInitTypeDef RCC_OscInitStruct = {0};
    RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

/** Configure the main internal regulator output voltage
    */
    __HAL_RCC_PWR_CLK_ENABLE();
    __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
    /** Initializes the RCC Oscillators according to the specified parameters
    * in the RCC_OscInitTypeDef structure.
    */
    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;
    if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
    {
      Error_Handler();
    }
    /** Initializes the CPU, AHB and APB buses clocks
    */
    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;

if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_5) != HAL_OK)
    {
      Error_Handler();
    }
}
```
** 6、代码使用rt官网can驱动**

```c
/*
 * 程序清单：这是一个 CAN 设备使用例程
 * 例程导出了 can_sample 命令到控制终端
 * 命令调用格式：can_sample can1
 * 命令解释：命令第二个参数是要使用的 CAN 设备名称，为空则使用默认的 CAN 设备
 * 程序功能：通过 CAN 设备发送一帧，并创建一个线程接收数据然后打印输出。
*/

#include <rtthread.h>
#include "rtdevice.h"

#define CAN_DEV_NAME       "can1"      /* CAN 设备名称 */

static struct rt_semaphore rx_sem;     /* 用于接收消息的信号量 */
static rt_device_t can_dev;            /* CAN 设备句柄 */

/* 接收数据回调函数 */
static rt_err_t can_rx_call(rt_device_t dev, rt_size_t size)
{
    /* CAN 接收到数据后产生中断，调用此回调函数，然后发送接收信号量 */
    rt_sem_release(&rx_sem);

return RT_EOK;
}

static void can_rx_thread(void *parameter)
{
    int i;
    rt_err_t res;
    struct rt_can_msg rxmsg = {0};

/* 设置接收回调函数 */
    rt_device_set_rx_indicate(can_dev, can_rx_call);

#ifdef RT_CAN_USING_HDR
    struct rt_can_filter_item items[5] =
    {
        RT_CAN_FILTER_ITEM_INIT(0x100, 0, 0, 0, 0x700, RT_NULL, RT_NULL), /* std,match ID:0x100~0x1ff，hdr 为 - 1，设置默认过滤表 */
        RT_CAN_FILTER_ITEM_INIT(0x300, 0, 0, 0, 0x700, RT_NULL, RT_NULL), /* std,match ID:0x300~0x3ff，hdr 为 - 1 */
        RT_CAN_FILTER_ITEM_INIT(0x211, 0, 0, 0, 0x7ff, RT_NULL, RT_NULL), /* std,match ID:0x211，hdr 为 - 1 */
        RT_CAN_FILTER_STD_INIT(0x486, RT_NULL, RT_NULL),                  /* std,match ID:0x486，hdr 为 - 1 */
        {0x555, 0, 0, 0, 0x7ff, 7,}                                       /* std,match ID:0x555，hdr 为 7，指定设置 7 号过滤表 */
    };
    struct rt_can_filter_config cfg = {5, 1, items}; /* 一共有 5 个过滤表 */
    /* 设置硬件过滤表 */
    res = rt_device_control(can_dev, RT_CAN_CMD_SET_FILTER, &cfg);
    RT_ASSERT(res == RT_EOK);
#endif

while (1)
    {
        /* hdr 值为 - 1，表示直接从 uselist 链表读取数据 */
        rxmsg.hdr = -1;
        /* 阻塞等待接收信号量 */
        rt_sem_take(&rx_sem, RT_WAITING_FOREVER);
        /* 从 CAN 读取一帧数据 */
        rt_device_read(can_dev, 0, &rxmsg, sizeof(rxmsg));
        /* 打印数据 ID 及内容 */
        rt_kprintf("ID:%x", rxmsg.id);
        for (i = 0; i < 8; i++)
        {
            rt_kprintf("%2x", rxmsg.data[i]);
        }

rt_kprintf("\n");
    }
}

int can_sample()
{
    struct rt_can_msg msg = {0};
    rt_err_t res;
    rt_size_t  size;
    rt_thread_t thread;
    char can_name[RT_NAME_MAX];

{
        rt_strncpy(can_name, CAN_DEV_NAME, RT_NAME_MAX);
    }
    /* 查找 CAN 设备 */
    can_dev = rt_device_find(can_name);
    if (!can_dev)
    {
        rt_kprintf("find %s failed!\n", can_name);
        return RT_ERROR;
    }

/* 初始化 CAN 接收信号量 */
    rt_sem_init(&rx_sem, "rx_sem", 0, RT_IPC_FLAG_FIFO);

/* 以中断接收及发送方式打开 CAN 设备 */
    res = rt_device_open(can_dev, RT_DEVICE_FLAG_INT_TX | RT_DEVICE_FLAG_INT_RX);
    RT_ASSERT(res == RT_EOK);
    /* 创建数据接收线程 */
    thread = rt_thread_create("can_rx", can_rx_thread, RT_NULL, 1024, 25, 10);
    if (thread != RT_NULL)
    {
        rt_thread_startup(thread);
    }
    else
    {
        rt_kprintf("create can_rx thread failed!\n");
    }

msg.id = 0x78;              /* ID 为 0x78 */
    msg.ide = RT_CAN_STDID;     /* 标准格式 */
    msg.rtr = RT_CAN_DTR;       /* 数据帧 */
    msg.len = 8;                /* 数据长度为 8 */
    /* 待发送的 8 字节数据 */
    msg.data[0] = 0x00;
    msg.data[1] = 0x11;
    msg.data[2] = 0x22;
    msg.data[3] = 0x33;
    msg.data[4] = 0x44;
    msg.data[5] = 0x55;
    msg.data[6] = 0x66;
    msg.data[7] = 0x77;
    /* 发送一帧 CAN 数据 */
    size = rt_device_write(can_dev, 0, &msg, sizeof(msg));
    if (size == 0)
    {
        rt_kprintf("can dev write data failed!\n");
    }

return res;
}
///* 导出到 msh 命令列表中 */
//MSH_CMD_EXPORT(can_sample, can device sample);

```
**二、调试**
  1、主函数直接调用can_sample初始化，程序执行到write的时候，会进入 size=0；
  2、近几天也查了相关资料，说是drv_can 驱动波特率设置不对，会是这个原因吗，不知道怎么查了
  
  请大家帮忙看看什么问题，野火开发板使用提供的keil代码测试过，可以发送数据