Scrolling/Interacting with an LCD screen Menu using keypad as input

Projects Programming
1

I've tried looking through youtube videos and other forum post, but I'm still unable to scroll through and select menus on my lcd screen using the keypad.

I'm using a Mega 2560 and all the pins are connected directly into the Arduino.

I also plan on adding submenus into the program just trying to solve this problem first.
Thank you in advance for the help!


#include<Keypad.h>
#include<Wire.h>
//#include<LCD.h>
#include<LiquidCrystal.h>


/************* LCD SCREEN PIN SETUPS ****************/

const int rs = 12, en = 11, d4 = 5, d5 = 4, d6 = 3, d7 = 2;
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);

/**************************************************KEYPAD SETUP**********************************************************************/

const byte numRows = 4; //number of rows on the keypad
const byte numCols = 4; //number of columns on the keypad
//keymap defines the key pressed according to the row and columns just as appears on the keypad

char keymap[numRows][numCols] =
{
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};

byte rowPins[numRows] = {36, 34, 32, 30}; //Rows 0 to 3
byte colPins[numCols] = {28, 26, 24, 22}; //Columns 0 to 3

//initializes an instance of the Keypad class
Keypad myKeypad = Keypad(makeKeymap(keymap), rowPins, colPins, numRows, numCols);

char keypressed;

/*******DEBOUNCING**************/
int count = 0;
int dt = 20; //debounce time ins ms
int switch1Value;
int switch1OldValue;


/*************** MENU CONTROL **********************/
String menuItems[] = {"Intake", "Set Alarm", "Counters", "Random"};
int menuPage = 0;
int maxMenuPages = round(((sizeof(menuItems) / sizeof(String)) / 2) + .5);
int cursorPosition = 0;

// Creating custom characters for the menu display
byte downArrow[8] = {
  0b00100, //   *
  0b00100, //   *
  0b00100, //   *
  0b00100, //   *
  0b00100, //   *
  0b10101, // * * *
  0b01110, //  ***
  0b00100  //   *
};

byte upArrow[8] = {
  0b00100, //   *
  0b01110, //  ***
  0b10101, // * * *
  0b00100, //   *
  0b00100, //   *
  0b00100, //   *
  0b00100, //   *
  0b00100  //   *
};

byte menuCursor[8] = {
  B01000, //  *
  B00100, //   *
  B00010, //    *
  B00001, //     *
  B00010, //    *
  B00100, //   *
  B01000, //  *
  B00000  //
};

/*****************FUNCTION PROTOTYPE*******************/
void main_Menu();
void Cursor();
void main_Menu_Operation();
void menuItem1();
void menuItem2();
void menuItem3();
void menuItem4();
int CheckInput(int k); //checks keypad input

/*************************************************MAIN CODE *****************************/
void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);

  //clearing and inititalizing lcd screen
  lcd.begin(16, 2);
  lcd.clear();
  // Creates the byte for the 3 custom characters
  lcd.createChar(0, menuCursor);
  lcd.createChar(1, upArrow);
  lcd.createChar(2, downArrow);

}

void loop() {
  // put your main code here, to run repeatedly:
  char keypressed = myKeypad.getKey();
  Serial.println(keypressed);

  main_Menu();
  Cursor();
  main_Menu_Operation();
  switch1Value = keypressed; // value will be 0 if pressed and 1 if not

  if ((switch1OldValue == NO_KEY) && (switch1Value != NO_KEY)) //detects falling edge -10
  {
    count++; //do your task on falling edge
    delay(dt); // delay to prevent unwanted readings
  }
  if ((switch1OldValue != NO_KEY) && (switch1Value == NO_KEY)) //rising edge
  {
    delay(dt); //adds delay to prevent undesirable readings

  }

  switch1OldValue = switch1Value;
  Serial.println(count);


}

void main_Menu()
{
  Serial.print(menuPage);
  lcd.clear();
  lcd.setCursor(1, 0);
  lcd.print(menuItems[menuPage]);
  lcd.setCursor(1, 1);
  lcd.print(menuItems[menuPage + 1]);
  if (menuPage == 0)
  {
    lcd.setCursor(15, 1);
    lcd.write(byte(2));
  }
  else if (menuPage > 0 and menuPage < maxMenuPages)
  {
    lcd.setCursor(15, 1);
    lcd.write(byte(2));
    lcd.setCursor(15, 0);
    lcd.write(byte(1));
  }
  else if (menuPage == maxMenuPages)
  {
    lcd.setCursor(15, 0);
    lcd.write(byte(1));
  }
}

//Function makes sure the cursor is in the correct position
void Cursor()
{
  for (int x = 0; x < 2; x++) //erasing current cursor
  {
    lcd.setCursor(0, x);
    lcd.print(" ");
  }
  if (menuPage % 2 == 0) //menu page is even
  {
    if (cursorPosition % 2 == 0) // cursor position is even
    {
      lcd.setCursor(0, 0);
      lcd.write(byte(0));
    }
    if (cursorPosition % 2 != 0) // cursor position is odd
    {
      lcd.setCursor(0, 1);
      lcd.write(byte(0));
    }
  }

  if (menuPage % 2 != 0) //menu page is odd
  {
    if (cursorPosition % 2 == 0) //cursor position is even
    {
      lcd.setCursor(0, 1);
      lcd.write(byte(0));
    }
    if (cursorPosition % 2 != 0) //cursor position is odd
    {
      lcd.setCursor(0, 0);
      lcd.write(byte(0));
    }
  }
}

void main_Menu_Operation()
{
  if (keypressed != NO_KEY)
  {
    switch (keypressed)
    {
      case 'A': // if A is pressed
        {
          switch (cursorPosition)
          {
            case 0:
              menuItem1();
              break;
            case 1:
              menuItem2();
              break;
            case 2:
              menuItem3();
              break;
            case 3:
              menuItem4();
              break;
          }
          //ButtonPressed = 1;
          main_Menu();
          Cursor();
          break;
        }
      case '2': // 2 on the keypad serves as the up button
        {
          //KEYPAD = 0;
          if (menuPage == 0) // start of menu page
          {
            cursorPosition = cursorPosition - 1;
            cursorPosition = constrain(cursorPosition, 0, ((sizeof(menuItems) / sizeof(String)) - 1));
          }
          if (menuPage % 2 == 0 && cursorPosition % 2 == 0) // even page even cursorPosition
          {
            menuPage = menuPage - 1;
            menuPage = constrain(menuPage, 0, maxMenuPages);
          }
          if (menuPage % 2 != 0 && cursorPosition % 2 != 0) // odd menu page and cursorPosition
          {
            menuPage = menuPage - 1;
            menuPage = constrain(menuPage, 0, maxMenuPages);
          }

          cursorPosition = cursorPosition - 1;
          cursorPosition = constrain(cursorPosition, 0, ((sizeof(menuItems) / sizeof(String)) - 1));

          main_Menu();
          Cursor();
          //ButtonPressed = 1;
          break;
        }
      case '8': // 8 on keypad is the downward button
        {
          //KEYPAD = 0;
          if (menuPage % 2 == 0 && cursorPosition % 2 != 0) //even menu page odd cursorPosition
          {
            menuPage = menuPage + 1;
            menuPage = constrain(menuPage, 0, maxMenuPages);
          }
          if (menuPage % 2 != 0 && cursorPosition % 2 == 0) // odd menuPage even cursorPosition
          {
            menuPage = menuPage + 1;
            menuPage = constrain(menuPage, 0, maxMenuPages);
          }

          cursorPosition = cursorPosition - 1;
          cursorPosition = constrain(cursorPosition, 0, ((sizeof(menuItems) / sizeof(String)) - 1));

          main_Menu();
          Cursor();
          //ButtonPressed = 1;
          break;
        }
      default:
        break;
    }
  }
}

/*
  int CheckInput(int k) //checks keypad input
  {
  int result = 0;
  if (k == 'A')
  {
    result = 1; //select
  }
  if (k == '2')
  {
    result = 2;// move up
  }
  if (k == '8') //move down
  {
    result = 3;
  }
  if (k == 'B') // move back
  {
    result = 4;
  }
  return (result);
  }

*/
void menuItem1() //Intake menu
{
  lcd.clear();
  lcd.setCursor(3, 0);
  lcd.print("Start Intake Process?");
  if (keypressed != NO_KEY)
  {
    switch (keypressed)
    {
      case 'B': //B will be used as a back button
        {
          break;
        }
      case 'A' :// something selected
        {
          //call intake function
          break;
        }
      default:
        break;
    }
  }
}


void menuItem2() //Setting dispensing schedule
{

  lcd.clear();
  lcd.setCursor(3, 0);
  lcd.print("Set Schedule");
  if (keypressed != NO_KEY)
  {
    switch (keypressed)
    {
      case 'B': //B will be used as a back button
        {
          break;
        }
      case 'A' :// something selected
        {
          //call the alarm function
          break;
        }
      default:
        break;
    }
  }
}


void menuItem3() //unassigned
{

  lcd.clear();
  lcd.setCursor(3, 0);
  lcd.print("Start Intake Process?");
  if (keypressed != NO_KEY)
  {
    switch (keypressed)
    {
      case 'B': //B will be used as a back button
        {
          break;
        }
      case 'A' :// something selected
        {
          //call the alarm function
          break;
        }
      default:
        break;
    }
  }
}

void menuItem4() //unassigned
{
  lcd.clear();
  lcd.setCursor(3, 0);
  lcd.print("Start Intake Process?");
  if (keypressed != NO_KEY)
  {
    switch (keypressed)
    {
      case 'B': //B will be used as a back button
        {
          break;
        }
      case 'A' :// something selected
        {
          //call the alarm function
          break;
        }
      default:
        break;
    }
  }
}```
2

Welcome to the forum

Where are you stuck ?

For a start, does the keypad work ?

3

Yes, the keypad does work I checked that, but when I go to press for example the 'A' button on the keypad it does not do what it is meant to do which is to select that menu option.

4

Break the problem down

Does the code ever call the main_Menu_Operation() function, for instance and, if so, what is the value of keypressed and cursorPosition when the function is entered ?

5

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