Comments on: ESP32 Capacitive Touch Sensor Pins with Arduino IDE

By: Markus

Markus — Wed, 03 Jul 2024 12:08:32 +0000

You’re using touch wrong!
The pin or metal foil needs an insulator. A plastic cover, a foil, etc.
Never directly touch the pin/wire/metal by itself. This wouldn’t form a capacitive coupling!

You can glue the metal foil inside of a housing, and touch on the outside – so your finger is earth potential, and forms a capacitor to the metal foil through the (non-conducting) housing material.

This way, you get more robustness, water tightness etc, as you are used from other touch applications.
If you have a metal part, you can use a small capacitor in series, like it is done in those metal lamps with touch functionality.
You can read in the guidelines from the typical IC suppliers:
microchip.com/downloads/en/Appnotes/Capacitive-Touch-Sensor-Design-Guide-DS00002934-B.pdf

By: Sara Santos

Sara Santos — Wed, 21 Jun 2023 10:26:52 +0000

In reply to wing. Hi. What do you mean?

By: wing

wing — Fri, 16 Jun 2023 11:59:24 +0000

I want to change the pin from 22 to 13 as I use esp32 S3, but it seems there is no pin assignment

By: Diego M

Diego M — Fri, 14 Apr 2023 17:32:32 +0000

When I Use the touch sensor with the function touchSetCycles( 33000, 6300 ); in the Arduino IDE it works fine, but hen I run the same code in Platform IO touchSetCycles( 33000, 6300 ); does not have the same effect in the sensitivity of the touch pad, why is that ?

By: Ahmad

Ahmad — Mon, 31 Oct 2022 06:38:05 +0000

Hello, is there any way to disable the capacitive touch feature on the ESP32? I am using those pins to read ADC signal, and whenever those pins were touched it would pull the input HIGH. I Couldn’t use pull up or pull down because the input I am reading were analog. Any clue? Thanks

By: Sara Santos

Sara Santos — Sat, 16 Jul 2022 17:16:48 +0000

In reply to Shiva.

Hi.
What code are you using?
Are you following a specific tutorial?
Regards,
Sara

By: Shiva

Shiva — Thu, 14 Jul 2022 08:52:55 +0000

Hello ,
I am checking the Deep Sleep Using Touchpad, But I am facing this issue in Serial Monitor when i touch the pin.
Guru Meditation Error: Core 1 panic’ed (Coprocessor exception)
14:22:03.541 -> Core 1 register dump:
14:22:03.574 -> PC : 0x400d0d13 PS : 0x00060e31 A0 : 0x8008124e A1 : 0x3ffbea80
14:22:03.674 -> A2 : 0x3ffbfe88 A3 : 0x00000001 A4 : 0x8008676a A5 : 0x00000000
14:22:03.773 -> A6 : 0x3ffbeb88 A7 : 0x00000001 A8 : 0x800d0d13 A9 : 0x3ffbeb10
14:22:03.839 -> A10 : 0x7fc00000 A11 : 0x00000000 A12 : 0x00000000 A13 : 0x3ffbeb10
14:22:03.939 -> A14 : 0x00000008 A15 : 0x00000000 SAR : 0x0000000a EXCCAUSE: 0x00000004
14:22:04.038 -> EXCVADDR: 0x00000000 LBEG : 0x400014fd LEND : 0x4000150d LCOUNT : 0xffffffff
14:22:04.137 -> Core 1 was running in ISR context:
14:22:04.170 -> EPC1 : 0x400d0d13 EPC2 : 0x00000000 EPC3 : 0x00000000 EPC4 : 0x40083f9b
14:22:04.270 ->
14:22:04.270 -> ELF file SHA256: 0000000000000000
14:22:04.303 ->
14:22:04.303 -> Backtrace: 0x400d0d13:0x3ffbea80 0x4008124b:0x3ffbeb40 0x4008124b:0x3ffbeb60 0x40083d81:0x3ffbeb80 0x4000bfed:0x3ffb1f30 0x400874d9:0x3ffb1f40 0x400e2137:0x3ffb1f60 0x400d0db8:0x3ffb1f90 0x400d1fad:0x3ffb1fb0 0x40086675:0x3ffb1fd0
14:22:04.535 ->
14:22:04.535 -> Rebooting…

By: John Price

John Price — Sat, 09 Apr 2022 21:41:49 +0000

In reply to K J Archer.

You might be dealing with a noise ‘glitch’ on the pin. I wrote a little example that helps deal with this you might want to check out. Good luck! Regards, John. https://github.com/digamesystems/CapacitiveTouchTest

By: fathima

fathima — Tue, 01 Mar 2022 09:12:55 +0000

I am working on ESP32 touch sensor to act as a liquid level sensor.
Please do guide me as i am really new to arduino

By: Helmuth Helfmann

Helmuth Helfmann — Fri, 25 Feb 2022 17:47:09 +0000

In reply to Dax Liniere.

Thanks for your reply.
I tested all GPIOs with the same effect.
But I tried touch with deepSleep and there were no “noise”.
Next I used interrupt: no false signals.