只要關燈，電腦自動關機(使用Arduino Leonardo)

 一、成果影片

二、應用情境：

1.夜深人靜，用完電腦。只想上床睡覺。只要關燈，電腦就關機。

三、使用技能：

1.使用Arduino Leonardo

2.光敏電阻-感應關燈

3.鍵盤-命令電腦關機

四、接線圖：

五、圖形化程式碼(ArduBlock)：

六、Arduino 程式碼

檔名：ProjectNo0001

內容：

#include <Keyboard.h>

/*

 These core libraries allow the 32u4 and SAMD based boards 

 (Leonardo, Esplora, Zero, Due and MKR Family) 

 to appear as a native Mouse and/or Keyboard to a connected computer.

 */

void setup(){  // put your setup code here, to run once:

  Keyboard.begin(); // initialize control over the keyboard

  Keyboard.releaseAll();

}

void loop(){  // put your main code here, to run repeatedly:

  if ( analogRead( A0 ) < 600 ) {

    PcShutDown();

  }

}

void PcShutDown() { //customised function

    pinMode(4,INPUT_PULLUP); //make pin 4 an input and turn on the pullup resistor so it goes high unless connected to ground

  if(digitalRead(4)==LOW){  // do nothing until pin 4 goes low

    Keyboard.press(131); //the key to press (ASCII code)

  }

  pinMode(4,INPUT_PULLUP); //make pin 4 an input and turn on the pullup resistor so it goes high unless connected to ground

  if(digitalRead(4)==LOW){  // do nothing until pin 4 goes low

    Keyboard.press('r'); //the key to press (ASCII code)

  }

  Keyboard.releaseAll();

  pinMode(4,INPUT_PULLUP); //make pin 4 an input and turn on the pullup resistor so it goes high unless connected to ground

  if(digitalRead(4)==LOW){  // do nothing until pin 4 goes low

    Keyboard.print("shutdown /s /f /t 0"); //Send the message

  }

  Keyboard.releaseAll();

  pinMode(4,INPUT_PULLUP); //make pin 4 an input and turn on the pullup resistor so it goes high unless connected to ground

  if(digitalRead(4)==LOW){  // do nothing until pin 4 goes low

    Keyboard.press(176); //the key to press (ASCII code)

  }

  Keyboard.releaseAll();

  delay( 5000 ); // waits a few milliseconds 

}

資料來源：
1.【Arduino冷知識5】

2.Keyboard

3.