I need help with tft screan and mega

hello everyone
i buy tft lcd screen and test it with uno it always give me blank screen and when i see serial monitor to know driver ID give me UC8230 and when i change
tft.begin(identifier); to tft.begin(0x8230); didn’t work but finally work with 0x9325
but now i try it with mega 2560 but didn’t work and give me blank screen again !!!
where is the problem ???

Photos of Uno, Mega and blank screen is NOT useful.
A photo or link to the pcb side of the display shield is helpful.

You have a regular "Blue 2.8 inch Mcufriend" Uno shield.

Install/upgrade MCUFRIEND_kbv library via the Library Manager.
Run the diagnose_TFT_controller sketch.

Edit MCUFRIEND_kbv.cpp to #define SUPPORT_8230

Run the diagnose_TFT_controller sketch.

Run all of the example sketches.

Please let me know if you have any problems.

David.

thank you i make what you say and problem was resolved but i have new problem the bmp from sd card not work from mega i think problem with spi mega in 50,51,52,53 so can help me again

The shield has the SD signals on 10 -13 i.e. the SPI pins on a Uno.
The Mega must use software SPI.

You must not only install a third party library but edit the config file too.
The showBMP_not_uno example gives instructions.

Explain what you do not understand.

David.

done , i do it thank you again but i want help again i just think to connect spi to mega using wire and change in code do you think it that possible?

Your Blue 2.8 inch shield has got an unpopulated 9x2 header. You can solder your SPI wires there instead of hacking the screen. Snip off 10-13 if you have chosen to wire SPI from the 9x2.

There is little point in moving the SPI. I give instructions how to use the SD card for 10-13 on a Mega. Slower than hardware SPI but it works.

David.

OK i understand you thank you