Arduino and clones using the ATmega2560.

Enable jtag on arduino mega 2560

avrdude -B 5 -P `pavr2cmd --prog-port` -c avrisp2 -p m2560
avrdude -B 5 -P `pavr2cmd --prog-port` -c avrisp2 -p m2560 -e -U efuse:w:0xFD:m -U hfuse:w:0x18:m -U lfuse:w:0xFF:m

Test

avrdude -B 5 -c atmelice -p m2560

Data-sheet