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Lesson 14 IR Receiver Module
Overview
Using an IR Remote is a great way to have wireless control of your project.
Infrared remotes are simple and easy to use. In this tutorial we will be connecting
the IR receiver to the MEGA2560, and then use a Library that was designed for this
particular sensor.
In our sketch we will have all the IR Hexadecimal codes that are available on this
remote, we will also detect if the code was recognized and also if we are holding
down a key.
Component Required:
(1) x Elegoo Mega2560 R3
(1) x IR receiver module
(1) x IR remote
(3) x F-M wires (Female to Male DuPont wires)
Component Introduction
IR RECEIVER SENSOR:
IR detectors are little microchips with a photocell that are tuned to listen to infrared
light. They are almost always used for remote control detection - every TV and DVD
player has one of these in the front to listen for the IR signal from the clicker. Inside
the remote control is a matching IR LED, which emits IR pulses to tell the TV to turn
on, off or change channels. IR light is not visible to the human eye, which means it
takes a little more work to test a setup.
There are a few difference between these and say a CdS Photocells:
IR detectors are specially filtered for IR light, they are not good at detecting visible
light. On the other hand, photocells are good at detecting yellow/green visible light,
and are not good at IR light.
IR detectors have a demodulator inside that looks for modulated IR at 38 KHz. Just
shining an IR LED won't be detected, it has to be PWM blinking at 38KHz. Photocells
do not have any sort of demodulator and can detect any frequency (including DC)
within the response speed of the photocell (which is about 1KHz)