Light-Dependent Resistors

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Description[edit]

An LDR is a light-dependent resistor. It changes it's resistance depending on the light falling onto the LDR.

How to connect it electrically[edit]

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


How to control it in MicroPython[edit]

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.

#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)


Code Example Arduino Nano Connect RP2040[edit]

A0 is the analog input with 16 bit resolution. It reads the analog value every second and print it to the console-

#Example usage for Arduino Nano
from machine import Pin, ADC
from time import sleep

analogPin = ADC(Pin(26))

while True:
  analogVal16 = analogPin.read_u16()
  print(analogVal16)
  sleep(1)

Related Tutorial Videos[edit]