3.5" DFRobot TFT LCD "Touch Won't Work" Help

[kgray9]

Hello!

I am building a speedometer project with:
3.5" TFT LCD
FireBeetle ESP32
3.7V battery
GPS module

I have programmed a really good code for this same project but with an Arduino Uno. It worked amazingly, but I couldn't add touch because the library was way too big, even without any code. So I just changed to an ESP32 because of the huge program space.

Here is the display:

The Wiki has a schematic for the Uno, but without any of the three touch pins wired (SCL, SDA, and INT). How would I wire them?

I tried uploading the demo "UI_Button.ino" code, but it didn't work of course, because the touch pins aren't wired.

In this link (Touch response not working - ILI9488 driver based 3.5inch SPI TFT Display interfacing with Wemos Lolin32 (Esp 32 based ) MCU · Issue #1466 · Bodmer/TFT_eSPI · GitHub) I found that they attached the touch data out (SDA) to the MISO. I tried that, but to no avail. I also tried attaching SCL to SCK, but still nothing.

Does anyone have any ideas?
Thanks in advance!

[pylon]

You should connect the SDA to GPIO21 and SCL to GPIO22, INT isn't used with your module (GT911 chip).
Be sure to connect VCC to 3.3V and not 5V as you would for the UNO. Otherwise you fry the corresponding pins on the ESP32.

[kgray9]

Hello @pylon

Thank you! I should have tried that, but didn't think it was that simple. I guess I shouldn't always overlook the easiest idea to fix something, lol.

I wired SDA to SDA and SCL to SCL like you said, and it works perfectly with no problems.

Thanks again @pylon!