qmk_firmware/keyboards/abacus/rules.mk

# MCU name
MCU = atmega32u4

# Bootloader selection
BOOTLOADER = atmel-dfu

# Build Options
#   change yes to no to disable
#
BOOTMAGIC_ENABLE = no       # Enable Bootmagic Lite
MOUSEKEY_ENABLE = no        # Mouse keys
EXTRAKEY_ENABLE = yes       # Audio control and System control
CONSOLE_ENABLE = yes        # Console for debug
COMMAND_ENABLE = yes        # Commands for debug and configuration
# Do not enable SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
SLEEP_LED_ENABLE = no       # Breathing sleep LED during USB suspend
# if this doesn't work, see here: https://github.com/tmk/tmk_keyboard/wiki/FAQ#nkro-doesnt-work
NKRO_ENABLE = no            # USB Nkey Rollover
BACKLIGHT_ENABLE = no       # Enable keyboard backlight functionality
RGBLIGHT_ENABLE = yes       # Enable keyboard RGB underglow
BLUETOOTH_ENABLE = no       # Enable Bluetooth with the Adafruit EZ-Key HID
AUDIO_ENABLE = no           # Audio output on port C6
ENCODER_ENABLE = yes
DIP_SWITCH_ENABLE = yes
LTO_ENABLE = yes