//!  LiquidCrystal_PCF8574 library by Matthias Hertel

// This example shows various featues of the library for LCD with 16 chars and 2 lines.

#include <Arduino.h>
#include <Wire.h>
#include <LiquidCrystal_PCF8574.h>

LiquidCrystal_PCF8574 lcd(0x27); // set the LCD address to 0x27 for a 16 chars and 2 line display

int show = -1;

// 2 custom characters

byte dotOff[] = {0b00000, 0b01110, 0b10001, 0b10001,
                 0b10001, 0b01110, 0b00000, 0b00000};
byte dotOn[] = {0b00000, 0b01110, 0b11111, 0b11111,
                0b11111, 0b01110, 0b00000, 0b00000};

void setup()
{
    int error;

    Serial.begin(115200);
    Serial.println("LCD...");

    // wait on Serial to be available on Leonardo
    while (!Serial)
        ;

    Serial.println("Probing for PCF8574 on address 0x27...");

    // See http://playground.arduino.cc/Main/I2cScanner how to test for a I2C device.
    Wire.begin();
    Wire.beginTransmission(0x27);
    error = Wire.endTransmission();
    Serial.print("Error: ");
    Serial.print(error);

    if (error == 0)
    {
        Serial.println(": LCD found.");
        show = 0;
        lcd.begin(20, 4); // initialize the lcd

        lcd.createChar(1, dotOff);
        lcd.createChar(2, dotOn);
    }
    else
    {
        Serial.println(": LCD not found.");
    } // if

} // setup()

void loop()
{
    if (show == 0)
    {
        lcd.setBacklight(255);
        lcd.home();
        lcd.clear();
        lcd.print("Hello LCD");
        delay(1000);

        lcd.setBacklight(0);
        delay(400);
        lcd.setBacklight(255);
    }
    else if (show == 1)
    {
        lcd.clear();
        lcd.print("Cursor On");
        lcd.cursor();
    }
    else if (show == 2)
    {
        lcd.clear();
        lcd.print("Cursor Blink");
        lcd.blink();
    }
    else if (show == 3)
    {
        lcd.clear();
        lcd.print("Cursor OFF");
        lcd.noBlink();
        lcd.noCursor();
    }
    else if (show == 4)
    {
        lcd.clear();
        lcd.print("Display Off");
        lcd.noDisplay();
    }
    else if (show == 5)
    {
        lcd.clear();
        lcd.print("Display On");
        lcd.display();
    }
    else if (show == 7)
    {
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("*** first line.");
        lcd.setCursor(0, 1);
        lcd.print("*** second line.");
    }
    else if (show == 8)
    {
        lcd.scrollDisplayLeft();
    }
    else if (show == 9)
    {
        lcd.scrollDisplayLeft();
    }
    else if (show == 10)
    {
        lcd.scrollDisplayLeft();
    }
    else if (show == 11)
    {
        lcd.scrollDisplayRight();
    }
    else if (show == 12)
    {
        lcd.clear();
        lcd.print("write-");
    }
    else if (show == 13)
    {
        lcd.clear();
        lcd.print("custom 1:<\01>");
        lcd.setCursor(0, 1);
        lcd.print("custom 2:<\02>");
    }
    else
    {
        lcd.print(show - 13);
    } // if

    delay(1400);
    show = (show + 1) % 16;
} // loop()