Xbee Wireless Servo Control

Current Part:

2x Xbee WiFi Modules
2x PIC 18LF4520
2x LM317 Voltage Regulator
2x 5k Trimpot
4x 240Ω Resistors
2x 10kΩ Resistors
2x 3mm LEDs
2x 10uF Capacitors
2x 20 MHz Crystal
2x Breadboard
Jumper Wire
2x 9v Connecter
2x Battery Holder

Parts List Details
           The parts for both the transmitter and the receiver are listed above (notice a lot of duplicate 2x parts are listed. I'll describe the more important parts in greater detail below.

           This is the programmer that I use to load the firmware (software) that I create in Microchip's MPLAB onto the PIC 18F4520 microcontroller. It's a little expensive, but only comes as a one time cost. Once you have the programmer you can use it over and over to program almost every PIC that microchip makes.

PIC 18LF4520
           Normally I use the PIC 18F4520 series PIC in my articles but since the Xbee Modules are not +5v compatible (Xbee Modules use +3.3v) I decided to use the 'LF' series of the PIC. The 'LF' series of the PIC can run on a +3.3v power supply, which means we can use the same power supply going to the Xbee Module and the PIC Microcontroller.

Xbee WiFi Module
           These modules use the Xbee protocol (stack) for wireless communication, making them pretty darn reliable. The default speed setting for these modules is 9600 baud, so if you want to use these modules out of the box be sure your serial communication module is set to output at 9600 bps (as I do in this article).

LM317 Voltage Regulator
           This voltage regulator is a variable type which means it can output 1.25 - 37v. We use a 240&Omega resistor and a 5k trimpot circuit, then vary the trimpot value until the LM317 outputs the +3.3v that we need.

           Two standard sized breadboards are used to build the transmitter circuit and the receiver circuit. No secrets are surprises here, just a generic $10 breadboard.

Jumper Wire
           Standard breadboard jumper wire is used to connect everything together. Jumper wire kits are pretty easy to find, or you can always just go to the store and buy a few feet of wire and cut your own jumper wire with a pair of wire cutters!