Welcome to MattairTech!

Your Shopping cart is empty.

Skip to Main Content »

ATmega32U2 USB Development Board, Arduino compatible

Availability: In stock

Only 1 left
Accepting MC, VISA, AMEX, Discover, PayPal

Quick Overview

Updated March 25, 2016: Arduino 1.6.7 support. Download below.

Updated January 28, 2015: Drivers are now signed!

May 2, 2014: CDC Bootloaders now improved with better Arduino support (you can now ignore jumper) and bugfixes.

         The MT-DB-U2 is a development board for the Atmel ATmega32U2 USB microcontroller. The Atmega32U2 contains 32 KB of flash, 1 KB of RAM, 1 KB EEPROM, 22 programmable IO pins, and a USB device controller. The board has 32 pins in a dual inline configuration with 100 mil pin spacing and 600 mil row spacing which allows for easy mounting on a breadboard. It includes a mini USB connector, status LED, 16MHz crystal, reset button, HWB boot jumper, 3 PWM filters, and ISP header pads. A DFU bootloader or Arduino/AVRDUDE compatible bootloader comes preinstalled which allows programming of the chip over USB without an external programmer. The ISP header can be used with an external programmer for in-system programming. This header can be reconfigured to allow the MT-DB-U2 itself to be an ISP programmer, or to be used as a SPI master or slave. The board can be powered at 5V via USB, at 3.3V via the ATmega32U2 internal regulator and USB, or it can be powered externally (3V – 3.6V or 4.0V – 5.5V). All programmable IO pins are routed to headers, including those used by on-board hardware. The chip can be clocked externally, and the board is compatible with HV programming. The USB connections are also routed to header pins, which allows for panel-mount USB connectors. The PCB is high-quality with ENIG (gold-plated) finish, red soldermask, and white screenprinting showing the pinout. It measures approximately 1.7” x 0.8” (42mm x 20mm) and is 0.062” (1.6mm) thick. All firmware installed is open-source (MIT license) and available on the website. The firmware utilizes the LUFA USB library by Dean Camera, available at http://www.fourwalledcubicle.com/. The LUFA project includes examples using many different device classes (ie: storage, sound, MIDI, HID).

There are three bootloaders available. Please select below.
CDC:Recommended! Arduino and AVRDUDE compatible
DFU:FLIP compatible
Atmel DFU:FLIP compatible (External pullup resistor required!)
With this option, the factory default fuse and lockbit settings will be used. The Atmel bootloader does not support the LED, will not allow reading of the FLASH (other than verification), has certain lock bits set, and REQUIRES AN EXTERNAL PULLUP RESISTOR for the HWB pin. If you need to protect your code from being read but lack an external programmer to set the lockbits, choose the Atmel bootloader.

ATmega32U2 development board

Double click on above image to view full picture

Zoom Out
Zoom In

More Views

  • ATmega32U2 development board
  • Bottom of PCB
  • layout / pinout
  • Solder Jumpers

* Required Fields




*   ATmega32U2 USB microcontroller
*   USB device controller, Serial USART, and SPI communications
*   2 timers with 5 PWM channels
*   Arduino compatible
*   CDC (Arduino/AVRDUDE) or DFU (FLIP) bootloader preinstalled
*   Bitlash preinstalled (Arduino command shell)
*   ISP header pads (program chip using external programmer)
*   16MHz crystal
*   Green Status LED
*   3 RC PWM filters on each output compare pin of 16-bit timer 1 (can be disconnected)
*   Reset button
*   Bootloader selection jumper
*   Mini USB connector
*   Can be powered via USB at 5V (Vbus) or 3.3V (ATmega32U2 internal regulator)
*   Can be powered externally at 3V to 3.6V or 4V to 5.5V
*   All programmable IO pins routed to headers (including those used by on-board hardware)
*   USB pins routed to header pins (for panel-mount USB connector)
*   High-quality PCB with gold-plated finish and red soldermask
*   DIL-32 board, standard 0.1" pin spacing. Can be mounted on a breadboard.
*   Measures approx. 1.7” x 0.8” (42mm x 20mm) and 0.062” (1.6mm) thick.
*   LUFA USB library compatible (http://www.fourwalledcubicle.com/)


   User Manual

Arduino Support Features

* Arduino core and libraries ported to MattairTech USB boards
   21 digital, 4 PWM, 8 INT, 13 PCINT, SPI, USART1, 32KB FLASH, 1KB SRAM, 1KB EEPROM
* USB Serial interface replaces USART0
   Hardware maximum speed of 2Mbps
   Can use terminal emulator or serial monitor
   LED blinks when data is transferred (can be disabled)
   Uses the same methods as the original HardwareSerial.cpp (ie: Serial.println("Hello!"))
   Based on LUFA USB library by Dean Camera (www.fourwalledcubicle.com)
   USART1 also available; can be used at the same time
* Arduino/AVRDUDE compatible CDC bootloader preinstalled (optional)
* Bitlash Arduino command interpreter (bitlash.net) preinstalled
* All libraries included with Arduino download are now supported
* HID keyboard and mouse now supported
* Bootloader automatically jumps to sketch after it is uploaded, reset button returns to bootloader.
   Auto-reset to bootloader now supported as well.

Arduino Pin Mapping


Bitlash is an open source interpreted language shell and embedded programming environment. The preinstalled Bitlash firmware was compiled in the Arduino environment and supports Arduino functions (ie: dw() for digitalWrite()). A terminal emulator or the Arduino serial monitor may be used.

bitlash here! v2.0RC4 (c)2011 Bill Roy, bitlash.net -type HELP- 1706 bytes free
> print free, " bytes free"
1702  bytes free
> pinMode(13,1)
> d13=1

Commands arg else function help if ls peep print ps return rm run stop switch while
Functions abs ar aw bc beep br bs bw constrain delay dr dw er ew free inb max millis min outb pinmode printf pulsein random shiftout sign snooze

You may also be interested in the following product(s)

ATmega32U4 USB Development Board, Arduino compatible

ATmega32U4 USB Development Board, Arduino compatible

ZeptoProg II USB AVRISP mkII compatible Programmer and Multitool ( AVR ISP / XMEGA PDI / TPI )

ZeptoProg II USB AVRISP mkII compatible Programmer and Multitool ( AVR ISP / XMEGA PDI / TPI )


Hex Files

  Bootloader.hex  Revision 140502
The Bootloader.hex file is a CDC bootloader compatible with Arduino and AVRDUDE
May 2, 2014: CDC Bootloaders now improved with better Arduino support (you can now ignore jumper) and bugfixes.

  Bootloader_no_options.hex  Revision 140502
The Bootloader_no_options.hex file is a CDC bootloader compatible with Arduino and AVRDUDE
This version does not drive the LED or support the Arduino-specific features or the convenience features (see documentation).

  BootloaderDFU.hex  Revision 130416
The BootloaderDFU.hex file is a DFU bootloader compatible with FLIP

  BootloaderDFU_no_options.hex  Revision 130416
The BootloaderDFU_no_options.hex file is a DFU bootloader compatible with FLIP
This version does not drive the LED or support the convenience features (see documentation).

  bitlashdemo_MT-DB-U2.hex  Revision 130410
The bitlashdemo_MT-DB-U2.hex file is an Arduino command shell that comes preinstalled

  MT-DB-U2_Old_Demo.hex  Revision 110509
The MT-DB-U2_Old_Demo.hex file is an old demo program

  AVRISP-MKII.hex  Revision 130508
The AVRISP-MKII.hex file is an AVRISPmkII programmer for AVR Studio by Dean Camera (http://www.lufa-lib.org/). Set J1 to alternate position to use ISP header as an output to your target board. MT-DB-U2 and target must have the same operating voltage. Press reset to toggle between Atmel Studio and AVRDUDE mode. A 4MHz rescue clock is on pin C6. Latest version updates support for Atmel Studio 6.1.

Arduino 1.6.7 Support


Please visit the link above for more information and installation instructions.

Old Arduino Support (1.0.5) / Source Code

  MattairTech_Arduino_1.0.5.1.zip  Revision

Previously, Revision was erroneously posted, but this was a development version and was incomplete (it will add MIDI support). Please use instead.

MattairTech_Arduino_1.0.5.2.zip contains the Arduino 1.0.5 core files and the CDC bootloader. Version fixes the sketch not running when not connected to a USB host (ie: USB charger). 1.0.5 fixes several bugs (including BSoD's on Win7-64) and updates the Arduino core files and libraries to 1.0.5. Version 1.0.4 added HID keyboard and mouse support, added auto-reset support, updated LUFA to 130303, updated the Arduino core files and libraries to 1.0.4, updated the bootloaders, and added support for the new MT-DB-U6. Note that Arduino 1.0.5 requires the use of the updated inf file below. Please read the files INSTALL.txt and README.txt in the root directory.

  MattairTech_CDC_Arduino_Bootloaders.zip  Revision 140502
May 2, 2014: CDC Bootloaders now improved with better Arduino support (you can now ignore jumper) and bugfixes.
MattairTech_CDC_Arduino_Bootloaders.zip contains the source code for the LUFA CDC bootloader.

  MattairTech_Arduino_1.0.1.zip  Revision 1.0.1-1
MattairTech_Arduino_1.0.1.zip contains the Arduino 1.0.1 core files and the CDC bootloader.

  MattairTech_DFU_Bootloaders.zip  Revision 130416
MattairTech_DFU_Bootloaders.zip contains the source code for the DFU bootloader.

  MT-DB-U2_111014.zip  Revision 111014
MT-DB-U2_111014.zip contains the source code for the old demo.



Updated January 28, 2015: Drivers are now signed!
The MattairTech_CDC_Driver_Signed.zip file is required for the demo program and CDC bootloader if running Windows, when it will operate as a CDC-ACM device (virtual COM port). This driver supports XP (SP3), Vista (32 and 64 bit), Windows 7 (32 and 64 bit), and Windows 8. The old unsigned driver is available at https://www.mattairtech.com/software/MattairTech_CDC.inf. Linux does not require a download (drivers should already be installed).

The DFU Bootloader also requires a driver. This driver is included with FLIP (inside the USB folder of FLIP's directory).


This development board/kit is intended for use for FURTHER ENGINEERING, DEVELOPMENT, DEMONSTRATION, OR EVALUATION PURPOSES ONLY. It is not a finished product, and may not (yet) comply with some or any technical or legal requirements that are applicable to finished products, including, without limitation, directives regarding electromagnetic compatibility, recycling (WEEE), FCC, CE, or UL (except as may be otherwise noted on the board/kit). MattairTech LLC supplied this board/kit AS IS, without any warranties, with all faults, at the buyer's and further users' sole risk. The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user indemnifies Atmel from all claims arising from the handling or use of the goods. Due to the open construction of the product, it is the user's responsibility to take any and all appropriate precautions with regard to electrostatic discharge and any other technical or legal concerns.

The authors disclaim all warranties with regard to this software, including all implied warranties of merchantability and fitness. In no event shall any author be liable for any special, indirect or consequential damages or any damages whatsoever resulting from loss of use, data or profits, whether in an action of contract, negligence or other tortious action, arising out of or in connection with the use or performance of this software.


Portions of this code are copyright (c) 2009-2013 Justin Mattair (www.mattairtech.com)

This code uses the LUFA USB library Copyright (C) 2013, Dean Camera (www.fourwalledcubicle.com)
     and distributed under a modified MIT license (see files).
     The CDC and DFU bootloaders are modified versions from LUFA.

The Arduino core files are copyright (c) 2005-2013 David A. Mellis (www.arduino.cc),
     copyright (c) 2004-2010 Hernando Barragan (wiring.org.co),
     copyright (c) 2006 Nicholas Zambetti,
     and copyright (c) 2009 Brett Hagman.
     They are modified from the originals by Justin Mattair and retain the original LGPL 2.1 licensing (see files).

The Bitlash files are Copyright (C) 2008-2012 Bill Roy (bitlash.net)
     They are modified from the originals by Justin Mattair and retain the original BSD style licensing (see files).

Accepting MC, VISA, AMEX, Discover, PayPal