rtt使用hmc5883l磁力计的包，获取的3轴数据一直为0，是读取不到？

发布于 2021-01-23 17:56:52 浏览：1721 订阅该版

![捕获.PNG](https://oss-club.rt-thread.org/uploads/20210123/70ba84ba19d3a50094b25c74c0e3c6d8.png)
使用I2c1总线，mpu6050，bpm180，hmc5983l,除了hmc5983其他两个传感器都能读出数据。初始化，注册设备都没有问题。就是hmc5983读出的数据为0(无论是命令行读取还是代码读取)，.在arduino中可以读出三轴数据，排除设备坏掉了。

代码：

main.c(其他的mpu6050和bmp180的代码我没贴)  :

```/*
 * Copyright (c) 2006-2018, RT-Thread Development Team
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Change Logs:
 * Date           Author       Notes
 * 2018-11-06     SummerGift   first version
 */

#include <rtthread.h>
#include <rtdevice.h>
#include <board.h>
#include "sensor_inven_mpu6xxx.h"
#include <rtdbg.h>
#include "bmp180.h"
#include "sensor_intf_hmc5883.h"

#define DBG_TAG "main"
#define DBG_LVL DBG_LOG

//debug led
#define LED0_PIN  GET_PIN(A,8)

//i2c_bus
#define I2C_BUS_NAME          "i2c1"

rt_thread_t mpu6050_thread,hmc5983_thread,bmp180_thread,pwm_thread;

static void read_hmc5983_entry(void *parameter);

int main(void)
{

//hmc5983
	hmc5983_thread = rt_thread_create("hmc_pro",
                                  read_hmc5983_entry,
                                  I2C_BUS_NAME,
                                  1024,
                                  RT_THREAD_PRIORITY_MAX / 2,
                                  20);
  if (hmc5983_thread != RT_NULL)
  {
    rt_thread_startup(hmc5983_thread);
  }
	
    return RT_EOK;
}

static void read_hmc5983_entry(void *parameter)
{
	 
    rt_device_t dev = RT_NULL;
    struct rt_sensor_data sensor_data;
    rt_size_t res;

dev = rt_device_find("mag_hmc");
    if (dev == RT_NULL)
    {
        rt_kprintf("Can't find device:%s\n", "mag_hmc");
        return;
    }

if (rt_device_open(dev, RT_DEVICE_FLAG_RDWR) != RT_EOK)
    {
        rt_kprintf("open device failed!\n");
        return;
    }
    while (1)
    {
        res = rt_device_read(dev, 0, &sensor_data, 1);
        if (res != 1)
        {
            rt_kprintf("read data failed!size is %d\n", res);
            rt_device_close(dev);
            return;
        }
        else
        {
         //rt_kprintf("hmc5983l:%d,%d,%d,%5d\n",sensor_data.data.mag.x, sensor_data.data.mag.y, sensor_data.data.mag.z, sensor_data.timestamp);
        }
        rt_thread_mdelay(100);
    }
}

//初始化hmc5983
//init hmc5983
static int rt_hw_hmc5983_port(void)
{
	  struct rt_sensor_config cfg;
    cfg.intf.dev_name = "i2c1";         /* i2c bus */
    cfg.intf.user_data = (void *)HMC5883_ADDR;  /* i2c slave addr */
	  rt_hw_hmc5883_init("hmc",&cfg);
    return RT_EOK;
}
INIT_ENV_EXPORT(rt_hw_hmc5983_port);
```