digitalRead()

[Digital I/O]

描述

Reads the value from a specified digital pin, either HIGH or LOW.

語法

digitalRead(pin)

參數

pin: the number of the digital pin you want to read (int)

回傳

HIGH or LOW

Example Code

Sets pin 13 to the same value as pin 7, declared as an input.

int ledPin = 13;  // LED connected to digital pin 13
int inPin = 7;    // pushbutton connected to digital pin 7
int val = 0;      // variable to store the read value

void setup() {
  pinMode(ledPin, OUTPUT);  // sets the digital pin 13 as output
  pinMode(inPin, INPUT);    // sets the digital pin 7 as input
}

void loop() {
  val = digitalRead(inPin);   // read the input pin
  digitalWrite(ledPin, val);  // sets the LED to the button's value
}

Notes

If the pin isn’t connected to anything, digitalRead() can return either HIGH or LOW (and this can change randomly).

Unlike Arduino, the analog input pins (referred to as A0, A1, etc) of 86Duino cannot be used as digital pins.

參考

• [程式語法] pinMode()
• [程式語法] digitalWrite()

語法參考主頁面

86Duino 參考的文本是根據 Creative Commons Attribution-ShareAlike 3.0 License，部分文本是從 the Arduino reference 修改的。 參考中的代碼示例已發佈到公共領域。