What you need:

• 1x PC
• 1x SainSmart Due Atmel SAM3X8E ARM Cortex-M3 board
• 1x SainSmart UNO R3 ATmega328P Development Board Compatible With Arduino UNO R3
• 1x 1uF Capacitor
• Jump wires

Avrdude used as pograming software in Windows clicks on Start button and type, cmd to activate command line window.

Type on command line: avrdude–C avrdude conf-c arduino –p m16u2-vvv-U flash:w:Arduino—DUE-usbserial.hex:i

Used cd (change directory) command in windows to navigate to the folder where ovrdude.exe, avrdude.conf and Arduino –DUE-usbserial are located. I just copied them into the same directory to avoid long links.

Change com9 to the com port your UNO is connected to.

Change Arduino –DUE-usbserial .hex tho the filename of your updated hex file.

DUE  ATMEGA16U2 USB-Controller of DUE to be updated.

UNO used as ISP Programer

Connections:

RST-pin10

MIOSI-pin11

MISO-pin12

SCK-pin13

5V-5V

GND-GND

Arduino ISP sketch must be downloaded into the UNO. You find it in the Examples.

Capacitor with 1u F connected between Reset and GND.

This manual is provided by our SainSmart customer. Thanks a lot for his help here.