---

• Tutorial about setting up LIRC in Raspberry PI, http://alexba.in/blog/2013/01/06/setting-up-lirc-on-the-raspberrypi/.
• Run this command to install LIRC in Raspberry PI, sudo apt-get install lirc.
• After this I need to modify 2 configuration files.
  • The 1st is to edit /etc/modules.
  • The 2nd file I need to edit is /etc/lirc/hardware.conf.
• Edit those files with the configurations from this website, http://alexba.in/blog/2013/01/06/setting-up-lirc-on-the-raspberrypi/.
• Reset LIRC background service with this codes.

sudo /etc/init.d/lirc stop
sudo /etc/init.d/lirc start

• In latest Raspberry PI firmware (firmware version 3.18.x per 25th January 2015), there is an additional file that need to be edited, which is /boot/config.txt.
• You need to add this line into /boot/config.txt.

dtoverlay=lirc-rpi.gpio_in_pin=23.gpio_out_pin=22

• After changing /boot/config.txt restart the Raspberry PI.
• To send and receive signal with Raspberry PI, I need to specify which pin is used for the IR transmitter (IR LED) and which one is used as IR receiver.
• The components used are roughly as follow.
  • IR LED.
  • IR receiver (please note the frequency).
  • PN2222 transistor.
  • 10 Kilo Ohm resistor to be put between Raspberry PI GPIO pin and the PN2222 transistor.
• For this tutorial.
  • Pin 22 is for IR receiver.
  • Pin 23 is for IR LED.
• There are 4 diagrams to connect/wire everything up.
• There is "view the updated one here" schematics listed in the website. I think I would just stuck on that one.
• Testing IR receiver by running this commands.

sudo /etc/init.d/lirc stop
mode2 -d /dev/lirc0

• After this try to press some button in IR based remote to test.
• For testing IR LED I need a configuration file.
• This is like a dictionary that stores pattern for Raspberry PI.
• There is this method called, irrecord within LIRC library.
• Use irrecord --list-namespace to see valid names.
• The configuration file is stored in /etc/lirc/lircd.conf