My ITDB02 keeps being blank

I've bought a Arduino Uno, the
http://www.exp-tech.de/Shields/ITDB02-Arduino-Shield-V2-0--Arduino-kompatibel-.html
and the
http://www.exp-tech.de/Displays/3-2--TFT-LCD-Screen-Module--ITDB02-3-2S.html.

After uploading an unmodified copy of the UTFT_Textrotation_Demo the screen is backlighted but keeps being blank.
The adaptor shield is set to 5V operation voltage.
The Uno works, because a message printed with Serial.println() appears in the Serial Monitor.

What am I doing wrong?

Post your sketch... very hard to guess with no information about what you have done or not ne.

Bob

// UTFT_Textrotation_Demo (C)2012 Henning Karlsen
// web: http://www.henningkarlsen.com/electronics
//
// This program is a demo of the textrotation-functions.
//
// This demo was made for modules with a screen resolution 
// of 320x240 pixels.
//
// This program requires the UTFT library.
//

#include <UTFT.h>

// Declare which fonts we will be using
extern uint8_t BigFont[];
extern uint8_t SevenSegNumFont[];

// Uncomment the next line for Arduino 2009/Uno
UTFT myGLCD(ITDB32S,19,18,17,16);   // Remember to change the model parameter to suit your display module!

// Uncomment the next line for Arduino Mega
//UTFT myGLCD(ITDB32S,38,39,40,41);   // Remember to change the model parameter to suit your display module!

void setup()
{
  myGLCD.InitLCD();
  myGLCD.clrScr();
  myGLCD.setFont(BigFont);
}

void loop()
{
    myGLCD.print("Text rotation", 0, 0);
    myGLCD.setColor(0, 0, 255);
    myGLCD.print("0 degrees", 0, 16, 0);
    myGLCD.print("90 degrees", 319, 0, 90);
    myGLCD.print("180 degrees", 319, 239, 180);
    myGLCD.print("270 degrees", 0, 239, 270);

    myGLCD.setFont(SevenSegNumFont);
    myGLCD.setColor(0, 255, 0);
    myGLCD.print("45", 90, 100, 45);
    myGLCD.print("90", 200, 50, 90);
    myGLCD.print("180", 300, 200, 180);

  while (true) {};
}

You are not doing anything wrong. You have just bought hardware that is incompatible.

Your shield only supports 8bit display modules, and the display modules is a 16bit module.
You will never be able to get it working without extensive modifications to the shield.

/Henning

Thanks for your answer!
Is there a shield that support 16bits?

If you are not afraid of a little soldering you can use this: http://imall.iteadstudio.com/prototyping/kits/im120717002.html

You can probably find something similar already soldered on eBay or something as well. The main thing is that you should be looking for a pre-v2.0 shield.
These usually have jumpers to select between 8bit and 16bit modules.

Just be aware that a 16bit display module will use all the available I/O on the Uno just for the display. You will not be able to use the touch screen or the SD card slot.

/Henning