I, like many others, have this display: 7" inch TFT LCD Capacitive Touch SSD1963 Shield for Arduino Due (or MEGA 2560) Library.
I bought this from BuyDisplay website, EastRising Technology Co., Limited.
Better to draw a veil over the quality of the support.
I, like many others, have it connected through the shield to an Arduino Due.
The problem was that the screen turned off after the code gets loaded and only came back on as long as the reset button is depressed.
Just do the following few steps.
First of all, the correct main class constructor is this:
UTFT myGLCD(SSD1963_800, 38, 39, 40, 41); // just SSD1963_800 and not SSD1963_800480!
Just add in the void setup () section:
myGLCD.InitLCD(); // this should already be there
pinMode(8, OUTPUT); //backlight
digitalWrite(8, HIGH); //on
Make sure you connect a decent 5-volt power supply to Arduino shield.
They insist to use their old UTFT libraries that can be found on their website. I used the latest ones, instead.
Magic. It works.
Good luck.