Need help problem with my screen module

Other Hardware Displays
1

Hi everyone,

A while ago i bought this screen :

Here is the back of the screen:

I managed to get it working with UTFT and even UTFT_tinyFat for loading picture from a sd card.

My problem is that everything is too bright(maybe also too contrasted).

I have a video of my screen:

What the video shows (in order):
->light flickering and way too bright
->when i press the reset button of the arduino (i assume it cut all com between arduino and screen but keep the power on) i get the correct color of the picture displayed
->I load the "demo_landscape eample of UTFT
->During the uploading i have again correct color of the picture displayed
->The images load normally but still too bright and light flickery
->I load the UTFT_Bitmap example
->During the uploading i have again correct color of the picture displayed
->Everytimesomething change on the screen it it less bright (but still too much) for a millisecond
->I reset the board two time and every time it display the correct color immediately

My questions are :
-Why is it too bright ?
-Is my screen faulty ?
-How can i fix this it's driving me crazy :0

Please help

2

Hi and welcome.

Shouting doesn't help.

You have told about your problem and the product you are using.
Also about the libraries you've been using yet.

You didn't tell about how you have connected the Arduino and your screen.
And you haven't posted your code.
As you say the picture is OK when there is no interaction between the Arduno and the screen (which is probably the case during reset), the connection between these two is probably all right.
Yet we'll still need to see it.

Of course, when posting your code, you'll put it in [code] [/code] tags.
To make that easier, you could also click the # button above the edit screen and then paste it.

3

Sorry for the big font it was a cry of desperation not an angry yelling :slight_smile:

I forgot to say that i have an arduino Mega 2560 and i don't use a shield.

By going in the UTFT doc and multiple forums i got the following wiring:

GND => GND
VCC => 5v/3v same results (5v brighter)
RS => D38
WR => D39
RD => 3.3v.
DB8 => D22
DB9 => D23
DB10 => D24
DB11 => D25
DB12 => D26
DB13 => D27
DB14 => D28
DB15 => D29
CS => D40
RESET => D41
LED_A => 3.3v
SD_DO=> D50
SD_DIN => D51
SD_CS => D53
SD_CLK => D52

I don't use the pin's of the touchscreen part.

Somewhere in the doc of UTFT it says " connect Db0-Db7 to ground for 8 bit display modules, i tried and it doesn't change a thing.

The 3.3v and Gnd of the arduino are connected on a breadboard.

I tried putting a potentiometer between led_A and the 3.3v and i doesn't change the problem just dim the backlight.

Here is the first code of the video just for displaying ths cat picture

#include <tinyFAT.h>
#include <UTFT.h>
#include <UTFT_tinyFAT.h>

UTFT         myGLCD(ILI9325C, 38, 39, 40, 41);   // Remember to change the model parameter to suit your display module!
UTFT_tinyFAT myFiles(&myGLCD);

// List of filenames for pictures to display. 
char* files320[]={"PIC301.RAW"};

void setup()
{
  myGLCD.InitLCD();
  file.initFAT();
}

void loop()
{
  myFiles.loadBitmap(0, 0, 320, 240, "PIC302.RAW");
}

As you can see it's pretty simple, nothing uneccessary.

The UTFT does have brightness and contrast control fonction but only compatible with cpld-based display (no idea what it is).

4

You are writing the picture over and over agian.
If it has a chance of doing so, the sketch will try to do that millions of times per second.

Void loop () is called that way because it loops (dûhh).
Here's an advise you would normally not see coming from me:

Add a line that pauses execution for a while.
It would be something like

delay(10000);

That will halt about all operation of the Arduino.
See if that helps.

In general:
What's the point of writing something to the screen that is already there ?
Don't do that unless you're sure you need to.

5

Thanks for your answer Mas3, but adding a Delay doesn't change anything .