XBEE 5V Breakout

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This circuit lets you talk to an XBEE serial port with 5V power and just two signal lines: RX and TX.

XBEEs are great radio modules. You can buy them from adafruit, sparkfun, and digi-key or your favorite electronics dealer. They cost around $20 dollars for the cheapest, lowest-range variety. Unfortunately, they require 3.3 volts, they don't fit easily into a breadboard, and they have a bunch of pins that are unnecessary if you only want to use them for serial communication at 9600 bps (bits per second). So we designed this breakout board, which lets you power them with 5V, stepping it down to 3.3V with an on-board voltage regulator. It pulls out the RX and TX pins necessary for serial communication and that is all. The 4 lines are accessed via a breadboard-friendly 0.1" spaced header. Don't worry about all those pins that you need Windows, and/or the command line to configure them :( If you do want to configure your XBEE see this tutorial from bildr. You will also need a tool like XBEE USB explorer from Sparkfun. Lots of other great example projects on Digi's (the company that makes the XBEEs) example page.
Also check out our XBEE LED Display tutorial which wirelessly sends text to our Heart Matrix LED display. You can send text from the Arduino serial port window, or from programs written in java or C++, anything that can access the serial port can send text out on the XBEE.

Images

Unpopulated PCB

Unpopulated PCB

The is the board showing the footprint for the voltage regulator the transistor and the 4x10K ohm resistor array.
XBEE and Breakout

On the right is an XBEE board, at left is the XBEE plugged into the breakout board and the unpopulated breakout board is shown at the top.
XBEE into Robot

Here is the XBEE breakout board plugged into a robot so that it can be remotely controlled.
XBEE Joy Remote

This PCB uses a joystick, accelerometer and an XBEE to wirelessly control an XBEE Robot.
Schematic

XBEE connections for 5V arduino signals to resistor network array to voltage regulator, capacitors and NPN mosfet transistor. When hooking it up to an arduino or any microcontroller always remember that RX and TX are relative to the MCU. So the RX (receiving) pin on the XBEE breakout board needs to be connected to the micronctroller's TX (transmitting) pin. So for example on an arduino UNO or Dueminalove connect XBEE's TX to pin 0 and XBEE's RX to pin 1.
Board Design

Printed Circuit Board layout in EAGLE.

The is the board showing the footprint for the voltage regulator the transistor and the 4x10K ohm resistor array.

Video

RC Bot Video

This robot is controlled by the thumb joystick. The XBEE radio modules handle all the communication.

Code

Transmit Code Test

Transmit 5 bytes. Wait about a second or so between each transmission.

Download File

/* LucidTronix xbee simple transmit 
 * http://www.lucidtronix.com/tutorials/23
 * just transmit five different bytes
 * good test to make sure serial communication
 * is working.
 */
void setup() {
  Serial.begin(9600);    //initialize serial
}

void loop() {
  Serial.write(250);
  delay(900);
  Serial.write(251);
  delay(1100);
  Serial.write(252);
  delay(500);
  Serial.write(253);
  delay(1000);
  Serial.write(254);
  delay(1500);
}

Receive Code Test

This code receives the 5 different bytes sent by the above transmitting code and lights a different LED depending on which one is being received.

Download File

/* LucidTronix xbee simple transmit 
 * See the accompanying transmission code
 * http://www.lucidtronix.com/tutorials/23
 * just recevies five different bytes
 * lights up different LEDs connected to pins
 * 2,3,4 and 5, depending on which byte was last received.
 * Good test to make sure serial communication
 * is working.
 */
int leds[]  = {2,3,4,5};
int num_leds = 4;
void setup() {
  Serial.begin(9600);    	//initialize serial
  for (int i = 0 ; i < num_leds; i++ )
    pinMode(leds[i], OUTPUT);  
  for (int i = 0 ; i < num_leds; i++ )
    digitalWrite(leds[i], HIGH);
  delay(2000); 
  for (int i = 0 ; i < num_leds; i++ )
    digitalWrite(leds[i], LOW);   
  delay(2000); 
  for (int i = 0 ; i < num_leds; i++ )
    digitalWrite(leds[i], HIGH);
  delay(2000); 
}

void loop() {   
  delay(20); 
  while (Serial.available()){
    int getData = Serial.read();  //if yes, read it
    for (int i = 0 ; i < num_leds; i++ )
      digitalWrite(leds[i], LOW);  
    if(getData == 10){
  	  digitalWrite(leds[0], HIGH);
	}else if(getData == 250){
  	  digitalWrite(leds[1], HIGH);
	}else if(getData == 251){
  	  digitalWrite(leds[2], HIGH);
	}else if(getData == 252){
  	  digitalWrite(leds[3], HIGH);
	}else if(getData == 253){
  	  digitalWrite(leds[1], HIGH);
          digitalWrite(leds[2], HIGH);
	}else if(getData == 254){
  	  digitalWrite(leds[0], HIGH);
          digitalWrite(leds[1], HIGH);
          digitalWrite(leds[2], HIGH);
          digitalWrite(leds[3], HIGH);
	}
    delay(20);
  }
}

Downloads

Download EAGLE files and code

Download this project! Please enjoy. Use the comments section for questions or trouble with the code or the circuit.

Click Here to Download: Download EAGLE files and code

Parts

parts

Parts

Title	Description	#	Cost	Link	Picture
PCB XBEE Breakout	LucidTronix 5V Serial breakout board for the RX and TX XBEE pins	1	$4.0	Link
Header	Female header 2mm spacing 10 pin fits the XBEE radio modules	2	$1.11	Link
Voltage Regulator 3v3 SMD	IC REG LDO 3.3V .15A SOT23 Up to 6V input output 3.3V 150mA (Max) Value: 3.3V	1	$0.46	Link
BSS138	MOSFET N-CH 50V 220MA SOT-23 Value: MOSFET N-Channel, Metal Oxide	1	$0.25	Link
Capacitor	CAP CER 0.1UF 50V Y5V 0805 Value: 0.1µF	2	$0.1	Link