Method enableInterrupt

java/libraries/io/src/processing/io/GPIO.java:273–301

Enables an interrupt for an input pin @param pin GPIO pin @param mode what to wait for: GPIO.CHANGE, GPIO.FALLING or GPIO.RISING @see waitForInterrupt @see disableInterrupt

(int pin, int mode)

   *  @see disableInterrupt
   */
  protected static void enableInterrupt(int pin, int mode) {
    checkValidPin(pin);

    String out;
    if (mode == NONE) {
      out = "none";
    } else if (mode == CHANGE) {
      out = "both";
    } else if (mode == FALLING) {
      out = "falling";
    } else if (mode == RISING) {
      out = "rising";
    } else {
      throw new IllegalArgumentException("Unknown mode");
    }

    if (NativeInterface.isSimulated()) {
      return;
    }

    String fn = String.format("/sys/class/gpio/gpio%d/edge", pin);
    int ret = NativeInterface.writeFile(fn, out);
    if (ret < 0) {
      if (ret == -2) {    // ENOENT
        System.err.println("Make sure your called pinMode on the input pin");
      }
      throw new RuntimeException(NativeInterface.getError(ret));
    }
  }


  /**