TFT TOUCH SCREEN ONLY DISPLAYS WHITE!

Other Hardware Displays
1

Hello
I am needing help with my tft touch screen project.
The screen only displays white after I upload the code.
Here is the code:

#include _ADAFRUIT_TOUCHSCREEN_H_
#define _ADAFRUIT_TOUCHSCREEN_H_
#include <stdint.h>

class TSPoint {
 public:
  TSPoint(void);
  TSPoint(int16_t x, int16_t y, int16_t z);
  
  bool operator==(TSPoint);
  bool operator!=(TSPoint);

  int16_t x, y, z;
};

class TouchScreen {
 public:
  TouchScreen(uint8_t xp, uint8_t yp, uint8_t xm, uint8_t ym);
  TouchScreen(uint8_t xp, uint8_t yp, uint8_t xm, uint8_t ym, uint16_t rx);

  bool isTouching(void);
  uint16_t pressure(void);
  int readTouchY();
  int readTouchX();
  TSPoint getPoint();
  int16_t pressureThreshhold;

private:
  uint8_t _yp, _ym, _xm, _xp;
  uint16_t _rxplate;
};

#endif

Thank you for your help.

2

Go on. Your program has no screen. Of course it can't show anything.

Post a link to the actual display that you have bought e.g. Ebay sale.

Then someone might advise on display library and touch library.

David.

3

Thank you David
I have tried several programs with this screen and each time it does nothing.
I would have posted other code, but it exceeded the character limit.
A few other people using this screen have had the same problem.

Here is the link to the screen: Arduino tft touch screen - ebay.com

Here is the link to the tutorial that I was following: HowtoMechatronics.com - tft touch screen tutorial.

Natha

4

Thanks for the links. It makes all the difference.
The tutorial is for Mega2560 display shields with XPT2046 Touch chip.

Your display is Mcufriend. Install MCUFRIEND_kbv library via Library Manager. Install Adafruit_GFX library

The Touch panel is resistive. Install Adafruit_Touchscreen library

Always use the IDE Library Manager when possible.
Run the examples that come with each library.

If you have a problem, quote library version and example name.

David.

5

Thank you David

I am using an arduino UNO

Will that make a difference?
Do I need an arduino Mega?

Thank you

Natha

6

A Uno will be fine with your Red 2.4 inch Mcufriend shield.

7

Hello
The code that I am trying to use is at the bottom of this page.It exceeds the maximum character amount, so I was not able to post it.
When I try to upload the code, it shows the following error message,

Arduino: 1.8.7 (Mac OS X), Board: "Arduino/Genuino Uno"

sketch_dec06a:6:9: error: macro names must be identifiers
#define <ADAFRUIT_GFX.h>
^
sketch_dec06a:7:9: error: macro names must be identifiers
#define <ADAFRUIT_TOUCHSCREEN.h>
^
sketch_dec06a:39:2: error: #endif without #if
#endif
^
exit status 1
macro names must be identifiers

8

That tutorial is NOT suitable for your display.

Look at the photos. The tutorial display has got a blue pcb with 18x2 header pins (suitable for a Mega2560). The blue display will NOT fit on your Uno.

Your Red display fits on your Uno.
The libraries that I suggested have example programs. Try them.

David.

9

Hello David

Thank you so much.

I have got it to work now
Can’t get that code to work but found different code.

Thank you

Natha :slight_smile:

10

Well done.

I presume that you installed MCUFRIEND_kbv, Adafruit_GFX, Adafruit_Touchscreen libraries.

And ran the examples from Adafruit_Touchscreen and MCUFRIEND_kbv

It is always helpful to say which example or which web link you were using.

David.