How to enable my MKS TFT32_L V4.0

I have upgraded the motherboard to a Makerbase MKS SGen L 3D Printer Motherboard 32-Bit Controller, and I already have a MKS TFT32_L v4.0 lcd screen. The screen powers up, shows me the menus and buttons, but does not actually respond to the touching of the icons. To me it appears it is not being listened to by the motherboard firmware. When I upgraded the hardware and switched to Marlin 2.0 I used my original configuration.h and configuration_adv.h files, and corrected the updated syntax errors. I have looked through the config files and can see that it is currently still using the original entry that it used with the 8 bit motherboard. The description of the motherboard says " Compatible with all of MKS TFT Press screens." so it should be compatible. I have already gone to MKS site and downloaded their firmware for the touch screen and updated the touch screen to no avail. I also reflashed it with the original firmware it came with when I bought the original CUBE machine from Flsun. Any suggestions on what to do?

link to current configuration files [www.dropbox.com]

The TFT talks to the controller via a physical serial port

You have all physical serial ports disabled in your Configuration.h


You still need
#define SERIAL_PORT -1
This enables the real USB port on 32 bit controllers. (including a virtual serial over USB, but a TFT cannot use this)

You also need
#define SERIAL_PORT_2 0
This enables the physical serial port 0 on the controller for the TFT to talk to

Thank you very much. I now have #define SERIAL_PORT_2 0 added to the original #define SERIAL_PORT -1. and it works.

When I was running the 8 bit motherboard the seller made it very clear that I would have to disconnect the LCD when building and flashing new firmware. Is this still a requirement with the 32 bit and Marlin 2.x?

No longer and issue with MKS SGen L since TFT traffic is now separate from controller traffic.

On the 8 bit system TFT was probably on serial 0 as was usb/serial converter... this would interfere with firmware uploads

Thanks for both answer and explanation. I am a firm believer in understanding is learning.