/* LCD 2x16 example
   22.10.2024. Djordje Herceg
*/  

#include <Wire.h>
#include <LiquidCrystal_I2C.h>

#define KEY1 39
#define KEY2 36

LiquidCrystal_I2C LCD = LiquidCrystal_I2C(0x27, 16, 2);

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  Serial.println("LCD 2x16 example");
  LCD.init();
  LCD.backlight();
  LCD.setCursor(1, 0);
  LCD.print("This is a 2x16");
  LCD.setCursor(0, 1);
  LCD.print("line LCD display");
  delay(1000);

  LCD.clear();
  LCD.setCursor(0, 1);
  LCD.print("A: dec, B: inc");
  pinMode(KEY1, INPUT_PULLUP);
  pinMode(KEY2, INPUT_PULLUP);
}

int counter = 100;
bool pPressed=false;
bool qPressed=false;
char buffer[7];

void loop() {
  // put your main code here, to run repeatedly:
  static long mils=millis();

  int p = digitalRead(KEY1);
  int q = digitalRead(KEY2);

  if (p == LOW) {
    mils=millis();
    if (pPressed==false){
      counter--;
      pPressed=true;
    }
  }

  if (q == LOW) {
    mils=millis();
    if (qPressed==false){
      counter++;
      qPressed=true;
    }
  }

  sprintf(buffer, "%6d", counter);
  LCD.setCursor(0, 0);
  LCD.print(buffer);

  if ((millis()-mils>50) && (pPressed==true)){
    pPressed=false;
  }
  if ((millis()-mils>50) && (qPressed==true)){
    qPressed=false;
  }
  delay(10); // this speeds up the simulation
}