August 31, 2017

KH 341: IR Basics Part 1

46 minutes

Basics of IR Control

IR control is a BINARY communications system

It uses a series of "0" and "1" (off or on) to convey a value from a transmitter to a receiver
The "Transmitter" is an IR LED and the "Receiver is a photosensitive element that responds to IR light"
However... just being able to "see" if the IR LED is lit doesn't allow us to communicate.
We need to have a "protocol" that defines how long a "control sequence" is and how to read it.- In other words, I need to know when the sequence starts, and when it ends.

We're going to use the "IRremote" library which understands most of the POPULAR protocols

Demo of Reading IR Codes

Show Interface
Show codes
Show Hardware

Let's Assemble the hardware!

Parts

IR Receiver (AX-1838HS) and LED
Arduino Nano

Pinout of the IR Receiver

From left to right, looking at the front of the sensor

Let's Program!

First, we need to include the "IRremote" Library
Sketch > Include Library > Manage Libraries

#include // This is the library we need to speak IR protocols

#define IR_PIN 2 // The digital pin to which the IR Reciever is connected

IRrecv irrecv(IR_PIN); // Turn on the reciever
decode_results ircode; // Create a structure called "IRcode"

void setup()
{
Serial.begin(9600); // Start the Serial Port (for debug)
irrecv.enableIRIn(); // Start the receiver
}

void loop()
{
if (irrecv.decode(&ircode)) // IF the IR reciever has received a code, THEN run the following:
{
Serial.println(ircode.value, HEX); // Print the received code to the Serial Port (for Debug)
irrecv.resume(); // Wait for the next IR code
}
}

** This code is a basic IR code reader. It will receive an IR code from a remote, then print it to the serial console

Now that we know we can receive IR codes w/our Nano, let's DO something with it!

Code for this Episode can be found at the link below:

https://www.dropbox.com/s/qf0htfgfo5de9zb/KH341_IR.zip?dl=0

Hosts: Fr. Robert Ballecer, SJ and Megan Morrone

Connect with us!

Don't forget to check out our large library of projects at https://twit.tv/shows/know-how.
Join our Google+ Community.
Tweet at us at @PadreSJ and @Anelf3.

Thanks to CacheFly for the bandwidth for this show.

...more

View all episodes

By TWiT

4.5

3535 ratings