The 3.5” screen you posted a link to only uses pins 10, 11, 12, and 13 for the SD card, and can share 11, 12, and 13 with your other screen that uses SPI as long as you have a pin free to use for the select line. The hardest part is getting to the physical connections if the 3.5” screen is mounted onto the Arduino.
@b707 you are right. It is not worth the headache trying to wore both up and causing Al the problems. I did manage to find a new screen Here it is a SPI version of the 3.5”. I think this will work.
@b707 is right. There is way to many problems with wiring and maybe even in coding from what I’m seeing. I did manage to find a 3.5” SPI screen here that should work and both screens will be spi too.
Would This screen work?
Just an update I got my new 3.5" spi display and one problem I have is the fifth pin. on the 3.5" display the fifth pin is RS and on the 2.8" is a DC pin. for the most part the pinout is the same besides the fifth pins on each display. Not sure what to do about that and I would need to change subjects and end this thread.
The BIG problem I see is the screen drivers if they are not the same what then , I have seen Libraries only #define one Driver
@mikedb I know one the 3.5" is a ST9976U and the 2.8" is a ILI9341 driver. I'm right now trying only to get up the 3.5 display up and running.
Is this a problem?
Why do you need both displays has exact the same pinout?
I'm working on a home automated project that I would like to have two display. The first display will show values and second display will act as a menu I can select because of the touch screen. Yes I can do it all in one menu but it makes me back that I have to select one sensor and then menu goes away and then see the values of the sensor. And if I hit the back button then it goes to the menu. I put two screens that way I can always see the menu and select which I would like to see.