HI,
This video shows how to flash the hex file in Arduino Board.The tools used are AvrDudess,FreematicsBuilder and xloader.The hex file is flashed using Usb to Serial converter.
Related Links:
AvrDudess :https://blog.zakkemble.net/avrdudess-...
FreematicsBuilder:https://freematics.com/pages/software...
Xloader:https://github.com/binaryupdates/xLoader