qmk_firmware/keyboards/68keys/rules.mk

LAYOUTS = 68_ansi

MCU = atmega32u4
F_CPU = 16000000
ARCH = AVR8
F_USB = $(F_CPU)
OPT_DEFS += -DINTERRUPT_CONTROL_ENDPOINT
BOOTLOADER = atmel-dfu

BOOTMAGIC_ENABLE = no       # Virtual DIP switch configuration (+1000)
MOUSEKEY_ENABLE = no        # Mouse keys (+4700)
EXTRAKEY_ENABLE = yes       # Audio control and System control (+450)
CONSOLE_ENABLE = no         # Console for debug (+400)
COMMAND_ENABLE = no         # Commands for debug and configuration
SLEEP_LED_ENABLE = no       # Breathing sleep LED during USB suspend
NKRO_ENABLE = no            # USB Nkey Rollover
BACKLIGHT_ENABLE = no       # Enable keyboard backlight functionality on B7 by default
MIDI_ENABLE = no            # MIDI controls
UNICODE_ENABLE = no         # Unicode
BLUETOOTH_ENABLE = no       # Enable Bluetooth with the Adafruit EZ-Key HID
AUDIO_ENABLE = no           # Audio output on port C6