PiTFT Capacitive Display not responsive to touch

Hardware
1

Can anyone assist me in figuring out why my display is not registering touch? How can i test the hardware itself to confirm its not a hardware issue?

Am using a Pi 3B with the Adafruit PiTFT Plus.
I have set the display settings to the appropriate display. The display is showing everything properly but isnt registering touch.

(something to note is that there is a cursor in the middle of the screen. Not sure if this is normal or maybe some indicator of a problem. figured i’d mention it anyways.)

2

You can connect a keyboard and boot the Pi 3B using a standard non-Zynthian OS to verify that the hardware is working.

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4

Found one! I’ll test it out and report back here.

5

Good. I took a look at Adafruit product description and saw:

The display and touchscreen uses the hardware I2C Pins (SDA & SCL), SPI pins (SCK, MOSI, MISO, CE0) as well as GPIO #25 and #24. All other GPIO are unused and you can still share the I2C pins with sensors, LED drivers, etc. Since we had a tiny bit of space, there’s 4 slim tactile switches wired to four GPIOs, that you can use if you want to make a basic user interface. For example, you can use one as a power on/off button.

So there may be some conflict there with what Zynthian uses, depending on whether you’re trying to use full Zynthian kit (encoders-switches) or just a touchscreen interface.

6

As I can see here:

This display use the GPIO18 (on pin number 12) for controling the backlight with its PWM function. But this GPIO is also used by DAC hats.

So, if you were trying to use a DAC hat simultaneously with the display, this could be the reason.

Otherwise, for better and more appropriate diagnostics some debuging info will help us:

  • output of dmesg command
  • content of file /var/log/Xorg.0.log
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