Digital Data (Button)

This example shows how to use a DIGITAL DATA Command Panel as a Virtual Button to control a boolean value inside your running Arduino program. A Button is typically used when you need to trigger events in your Arduino project (e.g. starting or stopping a pump).

The difference with a Virtual Switch is that a Virtual Button is immediately deactivated by the Arduino program after reading its state, to simulate a click.

To illustrate this, let’s use Command Panel 0 as a Button to move a servo on pin 8. Each time the button is clicked, the servo moves 10°, and move back to 0° if its position exceeds 170°.

Wiring diagram

Connect a Servo on pin 8 and add an electrolytic capacitor in parallel with the Servo power supply (beware of the polarity!!!). Connect it as close as possible to the Servo.

Sketch

Upload this sketch : 1_Basics \ 6_DigitalData

We start by attaching a Servo variable to pin 8 and we move the Servo to an initial position of 0°.

#include <HITIComm.h>

// Pins assignment
const int pin_Servo = 8;

// Digital Data assignment
const int dd_VirtualButton = 0;

// Servo position
long pos = 0;

void setup()
{
  // initialize library
  HC_begin();

  // attach Servo to the pin. Move servo to position 0°.
  HC_attachServo(pin_Servo, 0);
}

We then create a function to move the servo 10°, and to move it back to 0° if its position exceeds 170°. The position value is in millidegrees.

// move servo 10°. Move back to 0° if position exceeds 170°.
void moveServo()
{
  // increment position by 10°
  pos = pos + 10000;

  // reset position if it exceeds 170°
  if(pos > 170000)
    pos = 0;

  // move servo
  HC_servoWrite(pin_Servo, 0);
}

Inside the loop(), we read the state of the Button using HC_digitalDataRead(data). It the Button is activated, we immediately deactivate it, to simulate a button click, and we move the servo.

void loop()
{
  // communicate with HITIPanel
  HC_communicate();

  // if the Virtual Button is activated (from Command Panel 0)
  if (HC_digitalDataRead(dd_VirtualButton) == HIGH)
  {
    // immediately deactivate Button
    HC_digitalDataWrite(dd_VirtualButton, LOW);

    moveServo();
  }
}

Control Panels

1) Display the I/O Control Panels (“IO” button). 

2) The servo is at its initial position (0°).

3) Display the DATA Control Panels (“DATA” button). 

4) Click on the BUTTON several times. This will move the servo 10° each time.

5) Go back to the I/O Control Panels and check the servo position.