#include <LiquidCrystal.h>

LiquidCrystal lcd(2,0,4,16,17,5);
unsigned  char cont=250,x=0,contar=0,ativar_cont_bl=0;
int dl=0,cont_bl=0;
void setup()
{
  pinMode(19, INPUT_PULLUP);
   lcd.begin(16, 2); 
   lcd.setCursor(1,0);
}

void loop()
{
  dl++;delay(1);if(dl>15)dl=0;//delay contagem
  //tela
  lcd.setCursor(0,0);
  lcd.print("DISPLAY DE LCD");
  lcd.setCursor(0,1);
  lcd.print("Cont:");
  if(cont<0){lcd.print("-");lcd.print(cont);lcd.print("      ");} 
  if(cont>=0) {lcd.print(cont);lcd.print("      "); }
  //botões
  if(digitalRead(19)==0 && x==0){x=1;contar=!contar;}
  if(digitalRead(19)==0 && x==1){ativar_cont_bl=1;}
  if(digitalRead(19)==1 && x==1){x=0;ativar_cont_bl=0;}
  if(dl==15){
    if(contar==1)cont++;
  }
  if(cont==255)cont=0;
  //resetar contagem
  if(ativar_cont_bl==1){cont_bl++;delay(1);}
  if(cont_bl>30){cont=0;cont_bl=0;contar=0;}
}
//