Arduino board developement - Firmware related

Hello,

Actually, i'd made a arduino mega2560 r3 board. But would not able to run it like the Mega2560 board. Means the another controller inside that is ATmega16U2 - so how can i program the USB drivers and the firmware to run it like the actual mega board does.

Actually i have tried many times to load the usb drivers using that flip software and all but would not able to load it. so and so after doing it i have tried to load direct program to ATmega2560 using serial communications TX0 and RX0 using USB to TTL converter. and it works great. But the point is i could not able to load the firmware in ATmega16u2.

Kindly give the suggestions or the methods.

Waiting for your positive reply.

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