Microcontroller Boards
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The OSEPP™ Pro board is tailored to more professional users who do not mind a build-it-yourself approach compared to the OSEPP™ Uno. Unlike the Uno model this barebones board lacks headers, which gives this board a low profile. Pro users can choose to connect only the needed pins by mounting headers or soldering wires directly.


Microcontroller ATmega328P
Clock Speed 16 MHz
Flash Memory 32 KB
Operating Voltage 5V
Input Voltage 5-12 V
Digital I/O Pin Count 14 (including 6 for PWM output)
Analog Input Pin Count 6
Other Connections Serial communication header
ICSP for ATmega328P (requires header)
5V Lithium Polymer battery connector
5V DC power (requires connector)
Dimensions 2.07 x 2.11 x 0.30 inches (52.5 x 53.5 x 7.5 mm)
Power Source Lithium polymer battery or external DC power supply



  • 8-bit AVR RISC-based microcontroller running at 16 MHz
  • About 2/3 the size of the OSEPP™ Uno board
  • Flexible power source (lithium polymer battery or DC power)
  • ICSP header for programming microcontroller
  • Compatible with existing Arduino software libraries
  • Compatible with the Ethernet and Motor Controller Shields



The ATmega328P comes with the Arduino bootloader preloaded. Should you wish to update and/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 board comes with a resettable polyfuse on the power source. The fuse will trip when the current exceeds 500 mA on the input.



Stock Code Product Name



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



OSEPP Pro Schematic (PDF)
OSEPP Pro 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. Prepare for serial communication
    1. Connect the mini-USB end of the cable into the FTDI Basic Breakout
    2. Connect the other end of the cable into a USB port on your PC/Mac
    3. If your computer prompts for drivers, point it to the “drivers\FTDI USB Drivers” subfolder of the Arduino software, e.g. “C:\arduino-0022\drivers\FTDI USB Drivers”
    4. Connect the FTDI Basic Breakout to the 1×6 male pin header on the board. Make sure to match up the pins from the FTDI Basic Breakout to the markings on the board.
    5. You should now see the LED labeled Power near the slide switch light up
  3. Load the sketch
    1. Open the Arduino software
    2. Open the LED blink sketch: File menu > Examples > Basics > Blink
    3. Select the Pro board: Tools > Board > Arduino Pro or Pro Mini (5V, 16MHz) w/ ATmega328
    4. Select the serial port: Tools > Serial Port
    5. This is the serial port for the FTDI Basic Breakout. If you do not know which one this is, you can find out by going into Device Manager > Ports (COM & LPT), and look for a “USB Serial Port (COMx)”
    6. Upload the sketch: File > Upload to I/O Board
    7. Wait for the “Done uploading” message in the bottom blue status bar
  4. The LED near the pin 13 should now blink slowly
  5. Congratulations! You have successfully uploaded your first sketch to your board.