Touch Pin

[d.romeo]

Hi, I wanted to ask if it was possible to use the touch pins to detect touch when they are in pull-up or pull down mode with resistor, or more generally when they are not free but connected to an external voltage, for example 3.3V or 1.5V.
Thank you.

[ESP_Sprite]

Likely not. Touch works by charging and discharging the parasitic capacitance of the pad; any non-trivial resistance will wick that charge away.

[d.romeo]

Thank you. Does it also valve if the PIN is connected to GND?

[ESP_Sprite]

Obviously. No way to charge anything if the pin is shorted to ground.