From 99d9dabcdcb0c74ad1cee5049de1504177186bf4 Mon Sep 17 00:00:00 2001 From: ortegafernando Date: Sat, 29 Nov 2025 19:28:19 +0100 Subject: [PATCH] Update ADC.md Add info about 34, 35, 36, and 39: have NOT internal pull resistors --- docs/ADC.md | 2 ++ 1 file changed, 2 insertions(+) diff --git a/docs/ADC.md b/docs/ADC.md index ef1c91985b..c9dbf8d0e8 100644 --- a/docs/ADC.md +++ b/docs/ADC.md @@ -15,6 +15,8 @@ After wiring a peripheral to GPIO17 (A0) pin you have to configure it in **Confi The ESP32 board has eight ADC GPIO pins available (gpio32, gpio33, gpio34, gpio35, gpio36, gpio37, gpio38, gpio39 which are ADC1 channel in ESP32 platform, see [Tasmota ESP32 features](https://tasmota.github.io/docs/ESP32/). Usually only 6 available in ESP32 board: 32, 33, 34, 35, 36 and 39) which can be used for analog inputs. These can be used to read voltage at the ADC pin or to read the module supply voltage (VCC). All analog input pins support 3.3V. +!!! warning: gpio 34, 35, 36 and 39 are input only pins. These pins do NOT have internal pull-up or pull-down resistors. + After wiring a peripheral to the specified Analog Input GPIO pin, it can be configured in **Configure Module**: ![ADC configuration](_media/ADCesp32.png)