From Arduino Mega2560 to custom pcb

I am developing at a company that prototypes lots of different devices. For most of time i use atmel studio and my lovely mkII, but in this instance i am very short on time to make 10 working prototypes, so i switched to arduino. And in last month project got bigger and bigger and got to a point when megas 328 jsut did not have enought memory. Now i realised my project on MEGA2560(where it only took 32% and 33% of memory) and now i need to move the 2560 to my custom pcb.

We have partner that develops PCBs for us in 12 hours, but i got to a littel problem now. I wish to be able to later change program on the custom mega2560 so i want to add a FTDI chip right to the board(liek i did on my previous projects where i moved from uno to custom pcbs).

Problem is that i see that on arduino mega2560, there is atmega16u2 used as programming inbeetwen. I read somewhere in a footnote that i can go whit atmega 1280, on which i can burn bootloader and then program it directly via my mkII or avrusb.

So what i am asking is if some1 has a link to a guide to how to get Arduino Mega2560 or Arduino MEga1280 from arduino board to custom pcb?

If you google "atmega2560 breakout" and then look under the Images you will find lots of such boards.

This one looks interesting, though never see it before.

i know about the modules, but i wont be using that. actually i decided to jsut make pcb and use my avr mkII to burn bootloader on atmega2560, use arduino IDE to compile program, and burn it on chip via atmel studio and mkII :smiley: