ESP32 dev board GPIO question

[tczxusr]

I have a ESP32-wroom-32 based development board from Ideaspark, it features a ST7789 lcd display built in.
A link here to same one:
https://www.ebay.co.uk/itm/176425911571 ... 5976188579

Whenever I try to use pins 18+19 screen freezes, using pins 2+4 screen is blank. All other GPIO pins when used result in normal behavior with the screen updating as expected.

Here is code that references the pins-
-----------
// initialize the pin as an input
pinMode(waterDemandPin, INPUT_PULLUP); //INPUT);
// initialize the pin as an output
pinMode(pumpRunningPin, OUTPUT);
-----------

Can anyone shed any light on this? The article here indicates should be no problems with the pins I mentioned-
https://randomnerdtutorials.com/esp32-p ... nce-gpios/

Thanks.

[Sanazzy]

I gather you're trying to use those pins for other purposes?

From the listing description, it says that the display uses pins GPIOs 23, 18, 15, 2, 4.

So I would expect odd behaviour if you use those pins for something else.