ADC

<内核学习营>+坦然+探索者stm32f407板子的ADC测试光传感器实验

发布于 2018-09-07 20:30:10 浏览：2548 订阅该版

本帖最后由 luzixing 于 2018-9-12 11:46 编辑 *

实验要求：本实验是在探索者开发板完成的
硬件：至少有一路带ADC输入功能的GPIO，能够用来连接光环境传感器有一路串口用来做msh shell 终端
软件：
串口驱动
ADC驱动

实现的代码：

include

define LSENS_READ_TIMES 10 //定义光敏传感器读取次数,读这么多次,然后取平均值

define LSENS_CHANNEL 5

define LSENS_GET_PERIOD 500

define ADC_NAME “adc3”

/ 读取Light Sens的值 /
/ 0~100:0,最暗;100,最亮 /
void lsens_get_val(void* parameter)
{
rt_uint32_t temp = 0;
rt_uint32_t Lsens_val = 0;
rt_device_t dev;
rt_err_t result = RT_EOK;
while(1)
{
rt_uint8_t i;
rt_uint16_t val=0;

            for(i = 0;i < LSENS_READ_TIMES;i++)
            {
                    dev = rt_device_find(ADC_NAME);
                    if(!dev)
                    {
                            rt_kprintf("not found!<br>");
                    }
                    result = rt_device_open(dev, RT_DEVICE_FLAG_RDWR);
                    if(result != RT_EOK)
                    {
                            rt_kprintf("open faild! <br>");
                    }
                    if(rt_device_read(dev,LSENS_CHANNEL,&temp,sizeof(temp))!=sizeof(temp))
              {
                            rt_kprintf("channel %d: faild! <br>", LSENS_CHANNEL);
              }
                    val += temp;
                    rt_thread_delay(1);                /* #define RT_TICK_PER_SECOND 1000 */
            }
            temp = (rt_uint32_t)(val/LSENS_READ_TIMES);//得到平均值
            if(temp>4000) temp=4000;
            temp = (100-temp/40);
            if(temp != Lsens_val)
            {
                    Lsens_val = temp;
                    rt_kprintf("Lsens Vaule is:%d <br>", Lsens_val);  
            }
            rt_thread_delay(LSENS_GET_PERIOD-LSENS_READ_TIMES);
    }

}

int adc_test(void)
{
rt_thread_t tid;

    tid = rt_thread_create("Lsens",
            lsens_get_val, RT_NULL,
            512, RT_THREAD_PRIORITY_MAX/3, 20);
    if (tid != RT_NULL)
            rt_thread_startup(tid);
    return 0;