Arduino: How to modify fuses
From Luky-Wiki
Read fuses from Atmel mcpu
Following command read Low/High/Extended fuse configuration from mcpu + lock configuration:
avrdude -p m328p -c dragon_isp -P usb -U lfuse:r:-:h -U hfuse:r:-:h -U efuse:r:-:h -U lock:r:-:h
"Program" fuses
Following command set Low/High/Extended fuse and lock configuration (default configuration for Arduino UNO board):
avrdude -p m328p -c dragon_isp -P usb -u -U lfuse:w:0xff:m -U hfuse:w:0xde:m -U efuse:w:0x05:m -U lock:w:0x3f:m
Note: fuses are stored in eeprom memory. Due to HW restriction clearing memory set each cell to 0xFF. Therefore "unprogrammed" fuse have value of "1".
Default fuses (Arduino UNO)
lfuse: 0xff hfuse: 0xde efuse: 0x05 lock: 0x3f