（二）STM32L4（RT- Thread）——独立按键

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

#define DBG_TAG "main"
#define DBG_LVL DBG_LOG
#include <rtdbg.h>

int main(void)
{
    unsigned int count = 1;

    /* 设置 RGB 灯引脚的模式为输出模式 */
    rt_pin_mode(PIN_LED_R, PIN_MODE_OUTPUT);
	rt_pin_mode(PIN_LED_G, PIN_MODE_OUTPUT);
	rt_pin_mode(PIN_LED_B, PIN_MODE_OUTPUT);
    /* 设置 KEY 引脚的模式为输入模式 */
    rt_pin_mode(PIN_KEY0, PIN_MODE_INPUT);
	rt_pin_mode(PIN_KEY1, PIN_MODE_INPUT);
	rt_pin_mode(PIN_KEY2, PIN_MODE_INPUT);

    while (count > 0)
    {
        /* 读取按键 KEY 的引脚状态 */
        if (rt_pin_read(PIN_KEY0) == PIN_LOW)
        {
            rt_thread_mdelay(50);
            if (rt_pin_read(PIN_KEY0) == PIN_LOW)
            {
                /* 按键已被按下，输出 log，点亮 LED 灯 */
                LOG_D("KEY0 pressed!");
                rt_pin_write(PIN_LED_R, PIN_LOW);
            }
        }
		else if (rt_pin_read(PIN_KEY1) == PIN_LOW)
        {
            rt_thread_mdelay(50);
            if (rt_pin_read(PIN_KEY1) == PIN_LOW)
            {
                /* 按键已被按下，输出 log，点亮 LED 灯 */
                LOG_D("KEY1 pressed!");
				rt_pin_write(PIN_LED_G, PIN_LOW);
            }
        }
		else if (rt_pin_read(PIN_KEY2) == PIN_LOW)
        {
            rt_thread_mdelay(50);
            if (rt_pin_read(PIN_KEY2) == PIN_LOW)
            {
                /* 按键已被按下，输出 log，点亮 LED 灯 */
                LOG_D("KEY2 pressed!");
				rt_pin_write(PIN_LED_B, PIN_LOW);
            }
        }
        else 
        {
            /* 按键没被按下，熄灭 LED 灯 */
            rt_pin_write(PIN_LED_R, PIN_HIGH);
			rt_pin_write(PIN_LED_G, PIN_HIGH);
			rt_pin_write(PIN_LED_B, PIN_HIGH);
        }
        rt_thread_mdelay(10);
        count++;
    }
    return 0;
}