USB Volume control using Rotary encoder for android

Projects Programming
1

Hi Everyone,

I have a touch screen radio in my truck that has no physical knob to adjust the volume, one of these days I swear I will die trying to adjust it using the touch screen.
The radio runs android, so I figured I could use a rotary encoder to send volume up and down keys through the arduino as an HID, this worked however not exactly how I thought it would.
Turns out, my android radio has 2 separate volumes. When I rotate the rotary encoder, similar to a phone, a volume control pops up, however this does not change the volume level on the bottom fixed bar which stays at a certain volume, turns out it is sending this data directly to the car i.e. no keystroke.

I figured I could rethink my plan and change what would be a keyboard to a mouse, however I am struggling to accurately position the mouse where I need the keypress to happen. I understand absolute positioning goes against the entire concept that a mouse was made for, but the concept of relative positioning is hard to grasp for my use.

I found an example sketch from someone on this forum that would locate the mouse to the bottom left, move up slightly to the right at a diagonal, do a circle with the mouse then return to the same location. No matter if you moved the mouse during that operation, it would always return to the same spot. I would very much like to not have someone just give me the answer, but rather point me in the direction of how I could better understand the code that is written in this example. I really just need to understand how the positioning it always repeating back to a 0 location, my positioning is 720 pixels from the left and my understanding is that I can only travel 127 (not even sure the unit, I dont think pixels).

If anyone could point me in the right direction I would be greatly appreciated!

The code I would like to better understand is below, not so much the circle, but the exact positioning.

/*
  Demo of moving the mouse in a smooth circle without delay
  or blocking of the loop
*/
#include <Mouse.h>
void setup() {
  delay(1000);
}

void loop() {
  static float angle = 100;
  static int x, y;
  static unsigned long counter6;
  static unsigned long counter7;

  if (millis() > 10000 && counter6 < millis() - 10000) {
    counter6 = millis();
    angle = 0.0;
  }

  if (millis() > 20 && counter7 < millis() - 20 && angle < 100) {
    counter7 = millis();
    if (angle < 0.1 ) {
      Mouse.begin();
      // move to the corner of the screen
      for (int counter5 = 0; counter5 <= 100; counter5++) {
        Mouse.move(-127, 127, 0);
      }
      // move to a specific point on the screen
      Mouse.move(20,-30,0);
    }
    // move around a couple of times in a circle
    x = 9 * cos (angle);
    y = 9 * sin (angle);
    angle += .2; // increment the angle
    Mouse.move(x, y, 0);
    if (angle >= 4 * PI) {
      angle = 100;
      Mouse.end();
    }
  }
}
2 
for (int counter5 = 0; counter5 <= 100; counter5++) {
        Mouse.move(-127, 127, 0);
      }

Here it relatively moves the mouse -127, 127, 0 but it does so 100 times. that should make it end up in the corner think.

3

Deva_Rishi:

for (int counter5 = 0; counter5 <= 100; counter5++) {

Mouse.move(-127, 127, 0);
     }



Here it relatively moves the mouse -127, 127, 0 but it does so 100 times. that should make it end up in the corner think.

Thanks for the breakdown, that got me a ton of progress.
Basically, I now have the program working, coordinates are correct when I turn the rotary encoder left and right.
I attempted to add a Mouse.click(MOUSE_LEFT); function, which is wreaking some havoc.
It would appear that although the mouse.click is to follow the movement to the specified coordinate, I am getting multiple clicks, first one as it moves to the 0 point (inconveniently hits the A/C on button in my truck).
The code I am running is

#include <ClickEncoder.h>
#include <TimerOne.h>
#include <HID-Project.h>

#define ENCODER_CLK A0 // Change A0 to, for example, A5 if you want to use analog pin 5 instead
#define ENCODER_DT A1
#define ENCODER_SW A2

ClickEncoder *encoder; // variable representing the rotary encoder
int16_t last, value; // variables for current and last rotation value

void timerIsr() {
  encoder->service();
}

  void setup() {
  Serial.begin(9600); // Opens the serial connection used for communication with the PC. 
  Consumer.begin(); // Initializes the media keyboard
  encoder = new ClickEncoder(ENCODER_DT, ENCODER_CLK, ENCODER_SW, 4); // Initializes the rotary encoder with the mentioned pins
  Timer1.initialize(1000); // Initializes the timer, which the rotary encoder uses to detect rotation
  Timer1.attachInterrupt(timerIsr); 
  last = -1;
  delay(5000); //just in-case you fucked this up
  Mouse.begin();
}

void loop() {

    value += encoder->getValue();
  // This part of the code is responsible for the actions when you rotate the encoder
  if (value != last) { // New value is different than the last one, that means to encoder was rotated
    if(last<value) // Detecting the direction of rotation        
            // move to the corner of the screen
      {{for (int counter5 = 0; counter5 <= 100; counter5++) {
        Mouse.move(-120, 120, 0);
        delay(10);}
      // move to a specific point on the screen
      for (int counter6 = 0; counter6 <= 2; counter6++) {
        Mouse.move(79,-11,0); // left-right, top-bottom, keep at 0
        delay(5);
        Mouse.press(MOUSE_LEFT);
        delay(5);
        Mouse.release(MOUSE_LEFT);
        Mouse.end();
      }
  }}      else
            {{for (int counter5 = 0; counter5 <= 100; counter5++) {
        Mouse.move(-120, 120, 0);
        delay(10);}
      // move to a specific point on the screen
      for (int counter6 = 0; counter6 <= 2; counter6++) {
        Mouse.move(79,-3,0); // left-right, top-bottom, keep at 0
        delay(5);
        Mouse.press(MOUSE_LEFT);
        delay(5);
        Mouse.release(MOUSE_LEFT);
        Mouse.end();
      }}}}
      last = value;
      
      
      delay(50);
      

  delay(10); // Wait 10 milliseconds, we definitely don't need to detect the rotary encoder any faster than that
  // The end of the loop() function, it will start again from the beggining (the begginging of the loop function, not the whole document)
  }

Does anyone have any guidance for this issue?
Greatly appreciated.

4

Does anyone have any guidance for this issue?

If you want me (and others as well) to keep sifting through your code, then don't do stuff like this :

{{for (int counter5 = 0; counter5 <= 100; counter5++) {
        Mouse.move(-120, 120, 0);
        delay(10);}

or this :

 Mouse.end();
      }}}}
      last = value;

please indent your code properly (using ctrl-t is a way) and put closing braces on a line by them self. Like that it is a lot easier to read and see what is part of what loop or conditional execution. Delete unneeded white lines (they don't do anything but a few in a row just removes lines from view)
Please Change your code accordingly. I suspect you are looping the pressing and releasing, but it is just to hard to tell without counting braces, hence the indenting.

5

Thanks for the help, I had seen people's code written like that before but really didn't see the purpose, I get that now and have made the adjustments.

#include <ClickEncoder.h>
#include <TimerOne.h>
#include <HID-Project.h>

#define ENCODER_CLK A0 // Change A0 to, for example, A5 if you want to use analog pin 5 instead
#define ENCODER_DT A1
#define ENCODER_SW A2

ClickEncoder *encoder; // variable representing the rotary encoder
int16_t last, value; // variables for current and last rotation value

void timerIsr() {
  encoder->service();
}

void setup() {
  Serial.begin(9600); // Opens the serial connection used for communication with the PC.
  Consumer.begin(); // Initializes the media keyboard
  encoder = new ClickEncoder(ENCODER_DT, ENCODER_CLK, ENCODER_SW, 4); // Initializes the rotary encoder with the mentioned pins
  Timer1.initialize(1000); // Initializes the timer, which the rotary encoder uses to detect rotation
  Timer1.attachInterrupt(timerIsr);
  last = -1;
  delay(5000); //just in-case you fucked this up
  Mouse.begin();
}

void loop() {

  value += encoder->getValue();
  // This part of the code is responsible for the actions when you rotate the encoder
  if (value != last) { // New value is different than the last one, that means to encoder was rotated
    if (last < value) // Detecting the direction of rotation
      // move to the corner of the screen
    {{ for (int counter5 = 0; counter5 <= 100; counter5++) {
          Mouse.move(-120, 120, 0);
          delay(10);
        }
        for (int counter6 = 0; counter6 <= 2; counter6++) {
          Mouse.move(79, -11, 0); // left-right, top-bottom, keep at 0
          delay(5);
          Mouse.press(MOUSE_LEFT);
          delay(5);
          Mouse.release(MOUSE_LEFT);
          Mouse.end();
        }
      }
    }      else
    {{ for (int counter5 = 0; counter5 <= 100; counter5++) {
          Mouse.move(-120, 120, 0);
          delay(10);
        }
        for (int counter6 = 0; counter6 <= 2; counter6++) {
          Mouse.move(79, -3, 0); // left-right, top-bottom, keep at 0
          delay(5);
          Mouse.press(MOUSE_LEFT);
          delay(5);
          Mouse.release(MOUSE_LEFT);
          Mouse.end();
        }
      }
    }
  }
  last = value;
  delay(10);
}

Hopefully that is written in a way that is more understandable (although still likely not written in the ideal way)

6

(although still likely not written in the ideal way)

No that not, most people here have nothing on a line following an opening brace, and i fail to see what could be the purpose of 2 consecutive opening braces. anyway.

for (int counter6 = 0; counter6 <= 2; counter6++) {
          Mouse.move(79, -11, 0); // left-right, top-bottom, keep at 0
          delay(5);
          Mouse.press(MOUSE_LEFT);
          delay(5);
          Mouse.release(MOUSE_LEFT);
          Mouse.end();
        }

In this loop which runs 3 times, you move the mouse (relatively), press it, and release it. 3 times. is that the plan ? i mean you got tot the zero position, and then you move just a little and click. move a little more and click again and then once more.