// ---------------------------------------------------------
// I2C - LCD Anzeige
// Pinning: ESP32 D22 <=> SCL I2C_LCD
//                D21 <=> SDA
//                3V3 <=> Vcc
//                GND <=> GND
// Befehle:
// oLCD.init ()
// oLCD.backlight ();
// oLCD.clear ();
// oLCD.setCursor (iSpalte,iZeile);
// oLCD.print ("Hallo");
#include <LiquidCrystal_I2C.h>

#define I2C_ADDR    0x27
#define LCD_COLUMNS 20
#define LCD_LINES   4

#define RAUF 4
#define RUNTER 2
#define RECHTS 5
#define LINKS 3

LiquidCrystal_I2C oLCD (I2C_ADDR, LCD_COLUMNS, LCD_LINES);
// ---------------------------------------------------------
#include <string.h>
#include <stdio.h>

char sLCDText[30];

void LCDPrintCharSZ (int iSpalte,int iZeile,char cZeichen)
{
  char sBuchstabe[2];

  if (iZeile<0) return;
  if (iSpalte<0) return;
  if (iZeile>=LCD_LINES) return;
  if (iSpalte>=LCD_COLUMNS) return;

  sprintf (sBuchstabe,"%c",cZeichen);

  oLCD.setCursor (iSpalte,iZeile);
  oLCD.print (sBuchstabe);
}

void LCDPrintSZ (int iSpalte,int iZeile)
{
  int iIndex;

  for (iIndex=0;iIndex<strlen (sLCDText);iIndex++)
  {
    LCDPrintCharSZ (iSpalte+iIndex,iZeile,sLCDText[iIndex]);
  }
}

void Button_press (int iSpalte, int iZeile)
{
  int iButton_right;
  int iButton_left;
  int iButton_down;
  int iButton_up;

  for (;;)
  {
    iButton_right = digitalRead(RECHTS);
    iButton_left = digitalRead(LINKS);
    iButton_down = digitalRead(RUNTER);
    iButton_up = digitalRead(RAUF);

    if (iButton_right == 1)
    {
      iSpalte++;
    }
    if (iButton_left == 1)
    {
      iSpalte--;
    }
    if (iButton_down == 1)
    {
      iZeile++;
    }
    if (iButton_up == 1)
    {
      iZeile--;
    }
    LCDPrintSZ(iSpalte, iZeile);
    delay(200);
    oLCD.clear();
  }
}

void setup()
{
  oLCD.init();
  oLCD.backlight();

  strcpy (sLCDText,"1234567890");
  Button_press (15,0);
}

void loop()
{

}