Note: the ATmega644PA chip MUST have the following fuses set to work properly.

Set the fuses after programming & verifying the chip.

efuse = 11111100 = 0xFC (BODLEVEL = 4.3V)
hfuse = 11010111 = 0xD7 (JTAGEN = off, EESAVE = on, BOOTSZ = 512 bytes)
lfuse = 10100111 = 0xA7 (CKDIV8 = off, CKOUT = on, SUT=16K/4.1ms, CKSEL=0111 [full-swing crystal oscillator, 0.4-20MHz])
