It has eight times the RAM as the ever-popular 328p, and twice as much RAM as the ATMega2560p found in the Arduino Mega ... just make his own 1284p prototyping board. The board is laid out ...

Although [Stefan] explains that the boards were defective ... The heavy lifting is handled by an Arduino Mega 2560, which hooks up to what remains of the original system and controls the 27 ...

and Mega 2560 don't support the Debugger feature as they're powered by an AVR microcontroller. How Are The Boards Used With ...