Microcontroller Boards
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The OSEPP™ Fio board has wireless in mind. This board may connect to an XBee radio (sold separately) and has a connector for a lithium polymer battery which can be charged over the USB connection.


Microcontroller ATmega328P
Clock Speed 8 MHz
Flash Memory 32 KB
Operating Voltage 3.3 V
Input Voltage 3.35-12 V
Digital I/O Pin Count 14 (including 6 for PWM output)
Analog Input Pin Count 8
Other Connections Mini-USB (for charging only)
ICSP for ATmega328P (requires header)
XBee module socket
Lithium Polymer battery connector
Dimensions 2.56 x 1.10 x 0.47 inches (65.0 x 28.0 x 12.0 mm)
Power Source USB or external Lithium Polymer battery



•    8-bit AVR RISC-based microcontroller running at 8 MHz
•    On/off slide switch
•    Charging circuit for lithium polymer battery
•    Connector for interfacing with XBee modules
•    Flexible power source (USB or lithium polymer battery)
•    Compatible with existing Arduino software libraries



The ATmega328P comes with the Arduino bootloader preloaded. Should you wish to update or replace the bootloader, there are ICSP (In-Circuit Serial Programming) pin-outs that can be used in combination with a header (sold separately) for the ATmega328P.

The bottom of the board comes with pre-mounted headers for connecting to an XBee module for wireless applications.

To allow portability, the board can be powered by a lithium polymer battery. The board includes circuitry to allow the battery to be charged via a powered mini-USB connection. A resettable polyfuse on the USB path will trip when the current exceeds 500 mA, preventing board damage.



Stock Code Product Name



This board is based off of the Arduino Fio designed by Shigeru Kobayashi and
SparkFun Electronics, and is released under the Creative Commons Attribution
Share-Alike License. The original design can be found at



OSEPP Fio Schematic (PDF)
OSEPP Fio EAGLE Files OSEPP zip files


Learning Center:

What You Need


Uploading Your First Sketch

  1. Get the Arduino software if you have not already
    1. Download from http://arduino.cc/en/Main/Software
    2. Unzip the zip file to somewhere like C:\ (on Windows), so you will end up with a folder like C:\arduino-0022
  2. Supply power to the board
    1. Make sure the power supply is off
    2. Insert the positive wire (usually red in color) into the connector of the screw terminal marked ‘V+’
    3. Insert the negative wire (usually black in color to represent ground) into the connector of the screw terminal marked ‘GND’
    4. Turn on the power supply
    5. Check to see that the LED marked 3V3 is illuminated
  3. Pair the device to your PC/Mac
    1. On your PC/Mac, search for a Bluetooth device named ‘OSEPPBT’  Note: If you cannot find a device, try having the board further away from the BT receiver as there is a minimum distance for BT connections to work.
    2. Add the device
    3. When prompted for a passcode, use ‘12345’ (without the quotes)
    4. After the board is successfully paired, note the outgoing serial port number (we will need this later!)
  4. (Optional) Connect the LED and resistor
    1. Connect the anode (positive) pin of the LED to the pin header marked ‘13’ on the board
    2. Connect one end of the resistor in series to the cathode (negative) pin of the LED
    3. Connect the other end of the resistor to the pin header marked ‘GND’ on the board
  5. Load the sketch
    1. Open the Arduino software
    2. Open the LED blink sketch: File menu > Examples > Basics > Blink
    3. Select the BT board: Tools > Board > Arduino BT w/ ATmega328
    4. Select the serial port (from step 3d): Tools > Serial Port
    5. Press and hold down on the reset button on the BT board
    6. Upload the sketch: File > Upload to I/O Board
    7. When you see the “Binary sketch…” message in the black box, let go of the reset button
    8. Wait for the “Done uploading” message in the bottom blue status bar
    9. Press the reset button once to reset the board and load the program
  6. If you have attached an LED, it should now blink. You can also use a voltmeter to measure the voltage on the  pin to see the voltage change.
  7. Congratulations! You have successfully uploaded your first sketch to your board.