PIC 18F4520 Microcontroller
7805 +5v Regulator
IR Emitter LED
3x 10kΩ Resistors
2x 1kΩ Resistors
2x 2n2222 Transistors
2x 4 MHz Crystal
7x Green LEDs
Parts List Details
Some of the parts seen above maybe be familiar to you, but if any of them are not you can see a picture of it above. Below I have a better description of the main parts used in this tutorial.
PIC 18F452 - PIC 18F4520
Two microcontrollers will be used in this tutorial, one for the receiver and one for the transmitter. These will need to be programmed with the software that we will see in that section of this tutorial. I used a PIC 18F452 and 18F4520. These are actually the same and can be used interchangeably.
To Load the software onto the PIC microcontroller you will need a programmer. This programmer, called the PICkit2, is very popular and supported by the PIC manufacturer Microchip. It's low cost and will last.
This component detects the brightness of an infrared light beam. If an infrared LED shines right into a phototransistor, it switches on, otherwise it remains in the off state.
IR Emitter LED
IR Emitter LEDs are found in many places, most commonly in laptops and TV remote controls. These cheap little LEDs are what we will be using to transmit the serial communication data to the receiving phototranistor.
A small buffer circuit will be created using these general purpose transistors. This will allow us to switch the IR LED on and off with power directly from the power supply.
4 MHz Crystal
Both systems will use a 4 MHz crystyal clock, just to make things easier on us. You could use different clock rates for both microcontrollers, just make sure you have the serial communication baud rate set to 9600 BPS.
Wires & Breadboard
These will be used for connecting everything together. If you'd rather use a development board that you have, go ahead, the breadboard just creates a versatile platform that anyone can duplicate this work on.