介绍及代码

一共9个按键9盏灯。

按第一个按键亮一盏灯

按第二个按键亮两盏灯

按第三个按键亮三盏灯

按第四个按键亮四盏灯

依次类推。

例程代码

//#define io_11
//#define io_12

#define button_delay 5            //单按钮消除抖动延时
#define button_every_delay 50      //多按钮操作间隔

//io高低点吧状态标志位,0代表低电平，1代表高电平
bool io_flag[18]={0,0,0,0,0,0,0,0,0,0,0,0,0};

//按钮变化标志位，0代表无变化，1代表有变化
bool button_flag[18]={0,0,0,0,0,0,0,0,0,0,0,0,0};

int i;

void print_s(){
  for(int j=11;j<=9+i;j++)
  {
    digitalWrite(j,HIGH);
  }
  for(int j=10+i;j<=19;j++)
  {
    digitalWrite(j,LOW);
  }
}

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  for(i=2;i<=10;i++)
    pinMode(i,INPUT);
  for(i=11;i<=19;i++)
  {
    pinMode(i,OUTPUT);
    digitalWrite(i,LOW);
  }
  Serial.println("Init succ");
}
 
void loop() {
  // put your main code here, to run repeatedly:
 
  for(i=2;i<=10;i++)
  {
    if(digitalRead(i)==HIGH)
    {
      delay(button_delay);
      if(digitalRead(i)==HIGH)
        {
          if(io_flag[i]==0)
            {
              io_flag[i]=1;
              print_s();      //按钮按下，打印消息
              delay(button_every_delay);
            }
        }
    }
    
    if(digitalRead(i)==LOW)
    {
      delay(button_delay);
      if(digitalRead(i)==LOW)
        {
          if(io_flag[i]==1)
            {
              io_flag[i]=0;
              //print_s();      //按钮松开，打印消息
              delay(button_every_delay);
            }
        }
    }
  }
 
}

扩展

我们上面的例程里，每个按键对应的IO口都要接下拉电阻，其实arduino的IO口内部是有电阻的，我们可以通过程序将其配置为上拉电阻，这样我们的按键就不需要额外增加上拉电阻了，只需要接按键即可。

 我用esp32开发板做实验，只需如此这般

pinMode(2,INPUT_PULLUP);

例程1

void setup() {
  Serial.begin(9600);
  pinMode(2,INPUT_PULLUP);
}

void loop() {
  Serial.println(digitalRead(2));
  delay(500);
}

例程2

void setup() {
  Serial.begin(115200);
  pinMode(36,INPUT_PULLUP);
  pinMode(39,INPUT_PULLUP);
  pinMode(34,INPUT_PULLUP);
  pinMode(35,INPUT_PULLUP);
}
 
void loop() {
  Serial.print("36:");
  Serial.print(digitalRead(36));
  Serial.print("   ");

  Serial.print("39:");
  Serial.print(digitalRead(39));
  Serial.print("   ");

  Serial.print("34:");
  Serial.print(digitalRead(34));
  Serial.print("   ");

  Serial.print("356:");
  Serial.println(digitalRead(35));
  
  delay(500);
}