Scrolling through pages of a LCD using two buttons with Software Debouncing.

Projects Programming
1

Hey guys,
Im building a controller interface for my robot platform and i need to scroll through pages of a LCD Using two buttons.
The main idea is too press the forward button the LCD scrolls a page forward and same with Moving Back.

I have spent about 4 or 5 hours trying to sort out the debouncing, The main idea works, it just scrolls through way too quick.
Ive tried everything i could think of but i just cant get it right, Any Ideas?

Heres my code:

#include <LiquidCrystal.h>
int buttonB1 = 6; //Button to make scroll increase
int buttonF1 = 7; //Button to make decrease

LiquidCrystal lcd(12, 11, 5, 4, 3, 2); //LCD STUFF
//.....DEBOUNCING VARIABLES.......
int del = 50;
boolean buttonB;
boolean buttonF;
int buttonState;
int lastButtonState = LOW;
long lastDebounceTime = 0;
long debounceDelay = del;
int buttonState1;
int lastButtonState1 = LOW;
long lastDebounceTime1 = 0;
long debounceDelay1 = del;
//........................

int scroll; //THE MAIN VARIABLE THAT SCROLLS
int pages = 7; //The number of pages to scroll

void setup() {
  lcd.begin(16, 2); //Start The LCD
  Serial.begin(9600); //Serial for debugging
  pinMode(buttonB1, INPUT); //Usual Stuff
  pinMode(buttonF1, INPUT);
  scroll = 1; //Start at page 1
}

void loop() {
  debounce(); //Do all the debouncing
  if (buttonB == HIGH ){ //If The backward button is high decrease scroll by 1
    delay(300); //To try to slow the scrolling down
    scroll = (scroll - 1);
    previous = scroll;
  }
  else if (buttonF == HIGH){ //If The forward button is high increase scroll by 1
    delay(300);
    scroll = (scroll + 1);
    previous = scroll;
  }
  if (scroll > pages) scroll = 1; //If scroll is greater then the number of pages (7) scroll equals 1
  else if (scroll < 1) scroll = pages; //If scroll is less than 1 scroll equals 7
  delay(10);
  Serial.println(scroll);//For Debuging
  
  //...............................
  if (scroll == 1) fun1(); //If statments to run the functions
  else if (scroll == 2) fun2();
  else if (scroll == 3) fun3();
  else if (scroll == 4) fun4();
  else if (scroll == 5) fun5();
  else if (scroll == 6) fun6();
  else if (scroll == 7) fun7();
}
//............FUNCTIONS............
void fun1(){
  delay(5); //Give the LCD some time
  lcd.clear(); //Clear the LCD
  lcd.write("1"); //Write some data to LCD
}
void fun2(){
  delay(5);
  lcd.clear();
  lcd.write("2");
}
void fun3(){
  delay(5);
  lcd.clear();
  lcd.write("3");
}
void fun4(){
  delay(5);
  lcd.clear();
  lcd.write("4");
}
void fun5(){
  delay(5);
  lcd.clear();
  lcd.write("5");
}
void fun6(){
  delay(5);
  lcd.clear();
  lcd.write("6");
}
void fun7(){
  delay(5);
  lcd.clear();
  lcd.write("7");
}
void debounce() { //Debouncing Function
  //........COPIED FROM DEBOUNCE EXAMPLE...........
  int reading = digitalRead(buttonF1);
  if (reading != lastButtonState) {
    lastDebounceTime = millis();
  } 

  if ((millis() - lastDebounceTime) > debounceDelay) {
    buttonState = reading;
  }
  buttonF = buttonState;
  lastButtonState = reading;

  //.............DEBOUNCE SECOND BUTTON................... 

  int reading1 = digitalRead(buttonB1);
  if (reading1 != lastButtonState1) {
    lastDebounceTime1 = millis();
  } 

  if ((millis() - lastDebounceTime1) > debounceDelay1) {
    buttonState1 = reading1;
  }
  buttonB = buttonState1;
  lastButtonState1 = reading1;
}

Thanks In advance, :slight_smile:
Alex

2

You know do just check the button state to be HIGH to activate your routine. Use a similar method as you're already using in the debounce() routine and save the button state, run the action only if there is a state change, for example from LOW to HIGH. Remove all the delay() calls as they freezes your Arduino for a too long time.