#include <LiquidCrystal_PCF8574.h>

LiquidCrystal_PCF8574 lcd(0x27);

#define pin_I0 6

#define pin_I1 9

#define pin_I2 10

#define pin_I3 11

#define pin_I4 12

#define pin_I5 16

#define I0 digitalRead(pin_I0)

#define I1 digitalRead(pin_I1)

#define I2 digitalRead(pin_I2)

#define I3 digitalRead(pin_I3)

#define I4 digitalRead(pin_I4)

#define I5 digitalRead(pin_I5)

#define Q0 13

#define Q1 A1

#define Q2 A2

#define Q3 A3

#define Q4 A4

#define Q5 A5

char texto[] = "digital I/O";

byte pin_state_high[] = {0x00,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,0x00};

byte pin_state_low[] = {0x00,0x1F,0x11,0x11,0x11,0x11,0x1F,0x00};

void display_update() {

  lcd.setCursor(0, 0);

  lcd.print(texto);

  lcd.setCursor(0, 1);

  lcd.print("I: ");

  lcd.write(I0);

  lcd.write(I1);

  lcd.write(I2);

  lcd.write(I3);

  lcd.write(I4);

  lcd.write(I5);

  lcd.setCursor(0, 2);

  lcd.print("   012345");

  lcd.setCursor(0, 3);

  lcd.print("Q: ");

  lcd.write(digitalRead(Q0));

  lcd.write(digitalRead(Q1));

  lcd.write(digitalRead(Q2));

  lcd.write(digitalRead(Q3));

  lcd.write(digitalRead(Q4));

  lcd.write(digitalRead(Q5));

}

void setup() {

  // put your setup code here, to run once:

  pinMode(pin_I0, INPUT);

  pinMode(pin_I1, INPUT);

  pinMode(pin_I2, INPUT);

  pinMode(pin_I3, INPUT);

  pinMode(pin_I4, INPUT);

  pinMode(pin_I5, INPUT);

  pinMode(Q0, OUTPUT);

  pinMode(Q1, OUTPUT);

  pinMode(Q2, OUTPUT);

  pinMode(Q3, OUTPUT);

  pinMode(Q4, OUTPUT);

  pinMode(Q5, OUTPUT);

  lcd.begin(20, 4); // initialize the lcd

  lcd.createChar(0, pin_state_low);

  lcd.createChar(1, pin_state_high);

  delay(200);

  lcd.setBacklight(255);

}

void loop() {

  // put your main code here, to run repeatedly:

  digitalWrite(Q0, I0);

  digitalWrite(Q1, I1);

  digitalWrite(Q2, I2);  

  digitalWrite(Q3, I3);

  digitalWrite(Q4, I4);

  digitalWrite(Q5, I5);

  display_update();

}