+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