Touch Screen with Omega2+ and Arduino Dock 2

[Angus Ryan]

I have an Onion Omega 2+, Arduino Dock 2 and a 2.8 TFT Touch Shield for Arduino Uno.

I tested the touch screen with my Arduino Uno and it works perfectly, using the example code from the Adafruit libraries to test the touch screen.

My problem is when I then upload the same example to my Omega (while it’s in the Arduino Dock) I can’t get the touch screen to work. At first the display works fine however the touch screen functionality doesn’t work at all.

After a bit of research I found if I set via terminal:
fast-gpio set-input 15
fast-gpio set-input 16
fast-gpio set-input 17

I could get the touch screen working partially. That is, if I touch the screen the button changes state (as expected) except suddenly after that it’s as if the screen it repeatedly being tapped, without myself physically touching it again the 3 different buttons across the screen changes state as if theyre being touched when they are not. So if I can work out why the screen thinks it’s being touched when its not after the first press it’d solve my problem!

Can anyone enlighten me on what would cause this, and if possible point me in the right direction!

Thanks

[Yale E. Goldman]

@Angus-Ryan Did you solve your problem? I had something similar with the Dock 2 and a 3.5" TFT display. The problem was a conflict between I2C communication between the omega and the Dock's AVR chip with uses pins A4 and A5. But the pin corresponding to A4 resets the TFT display, So I cut this pin on the display and wired it to the Tx pin on the Dock 2, to do a hard reset when needed, but not during I2C transfers. The other added wire in the picture enables GPIO11 to receive data from the Arduino, but that is unrelated to the flakey operation I had before cutting the reset pin on the display.
Hope that's helpful.