Did I break my TFT LCD?

Other Hardware Displays
1

I just finished a project and the LCD (3.5" TFT LCD) has been working all the time.
Couple days go by and now that I want to use it, the TFT LCD doesn't respond to touching.
Looked at what coordinates it read when touching it and it only reads on value on the x-axis (1023) and y-axis works as normal.

See pic: Screenshot by Lightshot

Code handling the touch readings:

#include <LCDWIKI_GUI.h> //Core graphics library
#include <LCDWIKI_KBV.h> //Hardware-specific library
#include <stdint.h>
#include <string.h>
#include "TouchScreen.h"
 
#define YP A1  // must be an analog pin, use "An" notation!
#define XM A2  // must be an analog pin, use "An" notation!
#define YM 7   // can be a digital pin
#define XP 6   // can be a digital pin
 
#define MINPRESSURE 5
#define MAXPRESSURE 2000
#define TS_MINX 176
#define TS_MINY 176
#define TS_MAXX 918
#define TS_MAXY 953
 
LCDWIKI_KBV mylcd(ILI9486, A3, A2, A1, A0, A4); //model,cs,cd,wr,rd,reset
TouchScreen ts = TouchScreen(XP, YP, XM, YM, 300);
 
void setup(){
  mylcd.Init_LCD(); //initialize lcd
  mylcd.Set_Rotation(2);
  Serial.begin(9600);
}
 
void loop(){
    digitalWrite(13, HIGH);
      // a point object holds x y and z coordinates
      TSPoint p = ts.getPoint();
      digitalWrite(13, LOW);
    
      pinMode(YP, OUTPUT);
      pinMode(XM, OUTPUT);
    
      p.x = map(p.x, TS_MAXX, TS_MINX, 320, 0);
      p.y = map(p.y, TS_MAXY, TS_MINY, 480, 0);  
      
      // pressure of 0 means no pressing
      if (p.z > MINPRESSURE && p.z < MAXPRESSURE) {
        Serial.print("X = "); Serial.print(p.x);
        Serial.print("\tY = "); Serial.print(p.y);
        Serial.print("\tPressure = "); Serial.println(p.z);
      }
}

Tried running this demo sketch from the library that simply prints the x and y-coordinates and it read this when I didn't touch the screen.
Pic: Screenshot by Lightshot

This makes me think I may have damaged the hardware/screen, if it reads a constant preassure when I'm not touching it.

Does someone have any guess as to what this might be? I've tried other forums and no one knows, getting desperate.

2

What has changed ?
I expect that you will say nothing, but something obviously has. Is the project built using a breadboard ? They are notorious for having bad connections. However it is built, check each an every connection to make sure that it is sound and if possible check each one for electrical connectivity

Run the simplest possible sketch to test the touch functions. Does it work or does it exhibit the same problem ?

3

Srry, I have everything soldered and as I mentioned vaguely in the post, I tried the demo sketch that just reads the x and y touch values.
the tft lcd is on a breakoutshield that you can stick directly onto the arduino uno/mega (using a mega here).
Everything is configured exactly as before.
One thing that I did inbetween though. It sat on the table a couple days, then right before wanting to use it, I tried putting the arduino and lcd into a case I made myself, I decided to not use the case, it didn't look as good as I thought it would and was a little too tight to fit in place.
Now I've tried this before but maybe I was a little more rough with it this time as it hadn't been affected by prior test fittings, it was tight so maybe something broke in the hardware? Like it being constantly pressed down on one side due to being disformed somewhere from me trying to fit it into the casing, therefore giving a constant reading and preassure when not touching it (see the second photo I link to).
That's the only thing I can think of. I want to make sure that it's not just some stupid little thing I've deleted when cleaning up the code that messes up the values, before I buy a new one.
But from my memory and comparing with the demo sketch, everything looks to be there, especially since the demo sketch didn't even make any difference.
The delivery time is pretty long for the LCD.

4

So you have changed the code since it last worked. Did you keep a version of the working code ?

5

Well I never touched anything regarding that part of the code, I just deleted things that were commented out, that I hadn't deleted because I was unsure if I needed it, but since everything worked fine I took away all debugging print statements and such, I assign a very low probability to it being that as I tried it just before unplugging it from computer, and it worked.
But you know, our memories are not perfect.

BUT I tried now pressing the one side of the screen hard and then tapping on the screen while pressing down the side, and it worked all of a sudden, so my theory of me having messed up the hardware seems to be right.
See pic: Screenshot by Lightshot
What do you think, should I just bite down and buy a new one?

6

Please post the pictures that you linked to in previous posts rather than links to them

7

how?
I use lightshot, much easier than to download the screenshot and then upload.

8

You don't need to download or upload anything. Select the image then paste it here

9

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