RT-Thread API参考手册  3.1.1
嵌入式实时操作系统
adc_vol_sample.c
/*
* Copyright (c) 2006-2018, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2018-11-29 misonyo first implementation.
*/
/*
* 程序清单: ADC 设备使用例程
* 例程导出了 adc_sample 命令到控制终端
* 命令调用格式:adc_sample
* 程序功能:通过 ADC 设备采样电压值并转换为数值。
* 示例代码参考电压为3.3V,分辨率为12位。
*/
#include <rtthread.h>
#include <rtdevice.h>
#define ADC_DEV_NAME "adc1" /* ADC 设备名称 */
#define ADC_DEV_CHANNEL 5 /* ADC 通道 */
static int adc_vol_sample(int argc, char *argv[])
{
rt_adc_device_t adc_dev;
rt_uint32_t value, vol;
/* 查找设备 */
adc_dev = (rt_adc_device_t)rt_device_find(ADC_DEV_NAME);
if (adc_dev == RT_NULL)
{
rt_kprintf("adc sample run failed! can't find %s device!\n", ADC_DEV_NAME);
return RT_ERROR;
}
/* 使能设备 */
ret = rt_adc_enable(adc_dev, ADC_DEV_CHANNEL);
/* 读取采样值 */
value = rt_adc_read(adc_dev, ADC_DEV_CHANNEL);
rt_kprintf("the value is :%d \n", value);
/* 转换为对应电压值,3.3V对应12位最大值4096,数据精度乘以100保留2位小数 */
vol = value * 330 / 4096;
rt_kprintf("the voltage is :%d.%02d \n", vol / 100, vol % 100);
/* 关闭通道 */
ret = rt_adc_disable(adc_dev, ADC_DEV_CHANNEL);
return ret;
}
/* 导出到 msh 命令列表中 */
MSH_CMD_EXPORT(adc_vol_sample, adc voltage convert sample);