user48730: This board have pins to ESP8266's GPIOs.
What is Tout pin ?
On the back of the board it label pins :GPIO12, GPIO02, and another GPIO02 ? a continuity test shows that they are not connected. So what is it ?


user37622: From esp8266 datasheet:

TOUT - ADC pin. It can be used to test the power-supply voltage of VDD3P3 (Pin3 and Pin4) and the input power voltage of TOUT (Pin 6). However, these two functions cannot be used simultaneously.

from the pinout PDF of the Uno+WiFi board:


48730: <p><a href="https://www.aliexpress.com/item/33006588335.html?spm=a2g0s.12269583.0.0.5c4c4e9fviBsDu" rel="nofollow noreferrer">This</a> board have pins to ESP8266's GPIOs.</p>
<p>What is <code>Tout</code> pin ?
On the back of the board it label pins :<code>GPIO12</code>, <code>GPIO02</code>, and <strong>another</strong> <code>GPIO02</code> ? a continuity test shows that they are not connected. So what is it ?</p>
<p><a href="https://i.stack.imgur.com/LLKZz.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/LLKZz.png" alt="pic" /></a></p>
 37622: <p>From esp8266 datasheet:</p>
<blockquote>
<p>TOUT - ADC pin. It can be used to test the power-supply voltage of VDD3P3 (Pin3 and Pin4) and the input power voltage of TOUT (Pin 6). However, these two functions cannot be used simultaneously.</p>
</blockquote>
<p>from <a href="https://robotdyn.com/pub/media/0G-00005215==UNO+WiFi-R3-AT328-ESP8266-CH340G/DOCS/PINOUT==0G-00005215==UNO+WiFi-R3-AT328-ESP8266-CH340G.pdf" rel="nofollow noreferrer">the pinout PDF</a> of <a href="https://robotdyn.com/uno-wifi-r3-atmega328p-esp8266-32mb-flash-usb-ttl-ch340g-micro-usb.html" rel="nofollow noreferrer">the Uno+WiFi board</a>:</p>
<p><a href="https://i.stack.imgur.com/DIuTT.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/DIuTT.png" alt="enter image description here" /></a></p>
