3.5" ILI9486 (allegedly) + Mega2560 = no go

Oh, this new Forum is HORRIBLE.

Thanks for the photo. It means that we can recognise your actual hardware.

Install either UTFT library from RinkyDink i.e.
http://www.rinkydinkelectronics.com/library.php?id=51
Or TFT_HX8357 library from Bodmer i.e.

Unfortunately neither library is available from the IDE Library Manager. You have to install them manually.

I suggest that you start with UTFT examples e.g.
C:\Users\ ...\Documents\Arduino\libraries\UTFT\examples\Arduino (AVR)\UTFT_Demo_480x320\UTFT_Demo_480x320.ino

Edit the constructor statement from:

// Remember to change the model parameter to suit your display module!
UTFT myGLCD(CTE32HR,38,39,40,41);

to

    // Remember to change the model parameter to suit your display module!
    UTFT myGLCD(ILI9486,38,39,40,41);
  1. plug the shield into your Mega2560
  2. build and upload the sketch.

Now try all the other UTFT examples. Remember to edit the constructor statement in each sketch.

When you have UTFT working 100% you can try TFT_HX8357

  1. Edit User_Setup.h to define ILI9486
  2. Build and Run all of the TFT_HX8357 examples. You don't need to edit the sketches.

At each step, take notes with pencil and paper.

If you have a problem you can type from your notes.

David.

p.s. yes, MCUFRIEND_kbv is a lot more complicated to configure.