MCU_TARGET     = atmega328p
F_CPU          = 12000000
FLASHER        = avrdude -c usbasp -p $(MCU_TARGET)

usbasp: fuses
ifeq ($(F_CPU), 12000000)
	$(FLASHER) -B 1 -U flash:w:usbasp.atmega328p-12MHz.hex
else ifeq ($(F_CPU), 16000000)
	$(FLASHER) -B 1 -U flash:w:usbasp.atmega328p-16MHz.hex
else ifeq ($(F_CPU), 18000000)
	$(FLASHER) -B 1 -U flash:w:usbasp.atmega328p-18MHz.hex
else
	$(error setting of F_CPU is not supported.)
endif

fuses:
ifeq ($(F_CPU), 18000000)
	$(FLASHER) -B 300 -U lfuse:w:0xe7:m -U hfuse:w:0xd9:m -U efuse:w:0x05:m
else
	$(FLASHER) -B 300 -U lfuse:w:0xef:m -U hfuse:w:0xd9:m -U efuse:w:0x05:m
endif

shell:
	$(FLASHER) -B 200 -t