Editing Tutorial Analog IN

= Analog Input with MicroPyton and ESP32/ESP8266 =
In this part of the tutorial, we demonstrate how to read in an analog value using MicroPyton on ESP32/ESP8266. We also show how we can use the analog input to measure a changing resistor. This includes looking at the voltage range that can be measured the resolution of the analog-digital converter (ADC).

== Success criteria ==
* you can read in an analog value from the python prompt
* you understand how to build a voltage divider to read a sensor value from a changing resistor
* you can connect a Potentiometer, a slider, and a [[LDR]] to the ESP32/ESP8266 and read the value


== Related Components ==
The components are related to the [[LMUBox]]. For more components, see the [[Hardware List]. Many of the pages on actuators and sensors include additional examples.

=== Microcontroller ===
* [[ESP32 Web Kit]] with integrated OLED Display from Heltec 
* [[ESP8266 ESP-12F]] NodeMCU Module from AZDelivery 


=== Sensors (and physical controllers) ===
* [[LDR]] Light dependend resistor
* [[Potentiometer]] short Poti, changeable resistors as slider and knobs
* [[Analog Joystick]]

= Instructional Videos =
The videos are a first test... the ones marked with ** will be replaced over the next months with new versions.


== Analog Input - ADC - connecting a variable resistor ** ==
In this video on youtube (46:23) we show how to connect to read in an analog value with MicroPython. We also show how a sensor that is based on a changing resistance can be connected using a voltage divider: https://youtu.be/gjj5KyK2qGI  

<youtube>gjj5KyK2qGI  </youtube>


= Schematics and Code Example =

== Schematics for connecting to ESP32 ==
This should divide the voltage by half as both resistors are the same - you should read a value of about 2000 (assuming 12Bit resolution with a range of 0-4096)

[[File:R2.JPG|300px]]

Connecting the potentiometer (poti) or slider. The value you read is dependent on where your poti or slider stands.

[[File:Rpoti.JPG|300px]]

Connecting the light dependent resistor (LDR). The value you read is dependent on how bright it is.

[[File:Rldr.JPG|300px]]

== Code Example ==
This makes Pin 34 an analog input and set it to 12 bit. It reads the analog value every second and print it to the console-

<syntaxhighlight lang="python" line='line'>
#Example usage for ESP32
from machine import Pin, ADC
from time import sleep

analogPin = ADC(Pin(34))
analogPin.atten(ADC.ATTN_11DB)

while True:
  analogVal = analogPin.read()
  print(analogVal)
  sleep(1)
</syntaxhighlight>