RGB Lighting

Last updated 2 days ago

QMK has the ability to control RGB LEDs attached to your keyboard. This is commonly called underglow, due to the LEDs often being mounted on the bottom of the keyboard, producing a nice diffused effect when combined with a translucent case.

Planck with RGB Underglow

Some keyboards come with RGB LEDs preinstalled. Others must have them installed after the fact. See the Hardware Modification section for information on adding RGB lighting to your keyboard.

Currently QMK supports the following addressable LEDs on AVR microcontrollers (however, the white LED in RGBW variants is not supported):

  • WS2811, WS2812, WS2812B, WS2812C, etc.

  • SK6812, SK6812MINI, SK6805

These LEDs are called "addressable" because instead of using a wire per color, each LED contains a small microchip that understands a special protocol sent over a single wire. The chip passes on the remaining data to the next LED, allowing them to be chained together. In this way, you can easily control the color of the individual LEDs.

Usage

On keyboards with onboard RGB LEDs, it is usually enabled by default. If it is not working for you, check that your rules.mk includes the following:

RGBLIGHT_ENABLE = yes

At minimum you must define the data pin your LED strip is connected to, and the number of LEDs in the strip, in your config.h. If your keyboard has onboard RGB LEDs, and you are simply creating a keymap, you usually won't need to modify these.

Define

Description

RGB_DI_PIN

The pin connected to the data pin of the LEDs

RGBLED_NUM

The number of LEDs connected

Then you should be able to use the keycodes below to change the RGB lighting to your liking.

Color Selection

QMK uses Hue, Saturation, and Value to select colors rather than RGB. The color wheel below demonstrates how this works.

HSV Color Wheel

Changing the Hue cycles around the circle. Changing the Saturation moves between the inner and outer sections of the wheel, affecting the intensity of the color. Changing the Value sets the overall brightness.

Keycodes

Key

Aliases

Description

RGB_TOG

Toggle RGB lighting on or off

RGB_MODE_FORWARD

RGB_MOD

Cycle through modes, reverse direction when Shift is held

RGB_MODE_REVERSE

RGB_RMOD

Cycle through modes in reverse, forward direction when Shift is held

RGB_HUI

Increase hue

RGB_HUD

Decrease hue

RGB_SAI

Increase saturation

RGB_SAD

Decrease saturation

RGB_VAI

Increase value (brightness)

RGB_VAD

Decrease value (brightness)

RGB_MODE_PLAIN

RGB_M_P

Static (no animation) mode

RGB_MODE_BREATHE

RGB_M_B

Breathing animation mode

RGB_MODE_RAINBOW

RGB_M_R

Rainbow animation mode

RGB_MODE_SWIRL

RGB_M_SW

Swirl animation mode

RGB_MODE_SNAKE

RGB_M_SN

Snake animation mode

RGB_MODE_KNIGHT

RGB_M_K

"Knight Rider" animation mode

RGB_MODE_XMAS

RGB_M_X

Christmas animation mode

RGB_MODE_GRADIENT

RGB_M_G

Static gradient animation mode

RGB_MODE_RGBTEST

RGB_M_T

Red, Green, Blue test animation mode

Configuration

Your RGB lighting can be configured by placing these #defines in your config.h:

Define

Default

Description

RGBLIGHT_HUE_STEP

10

The number of steps to cycle through the hue by

RGBLIGHT_SAT_STEP

17

The number of steps to increment the saturation by

RGBLIGHT_VAL_STEP

17

The number of steps to increment the brightness by

RGBLIGHT_LIMIT_VAL

255

The maximum brightness level

RGBLIGHT_SLEEP

Not defined

If defined, the RGB lighting will be switched off when the host goes to sleep

Animations

Not only can this lighting be whatever color you want, if RGBLIGHT_EFFECT_xxxx or RGBLIGHT_ANIMATIONS is defined, you also have a number of animation modes at your disposal:

Mode number symbol

Additional number

Description

RGBLIGHT_MODE_STATIC_LIGHT

None

Solid color (this mode is always enabled)

RGBLIGHT_MODE_BREATHING

0,1,2,3

Solid color breathing

RGBLIGHT_MODE_RAINBOW_MOOD

0,1,2

Cycling rainbow

RGBLIGHT_MODE_RAINBOW_SWIRL

0,1,2,3,4,5

Swirling rainbow

RGBLIGHT_MODE_SNAKE

0,1,2,3,4,5

Snake

RGBLIGHT_MODE_KNIGHT

0,1,2

Knight

RGBLIGHT_MODE_CHRISTMAS

None

Christmas

RGBLIGHT_MODE_STATIC_GRADIENT

0,1,..,9

Static gradient

RGBLIGHT_MODE_RGB_TEST

None

RGB Test

RGBLIGHT_MODE_ALTERNATING

None

Alternating

Check out this video for a demonstration.

Note: For versions older than 0.6.117, The mode numbers were written directly. In quantum/rgblight.h there is a contrast table between the old mode number and the current symbol.

The following options can be used to tweak the various animations:

Define

Default

Description

RGBLIGHT_EFFECT_BREATHING

Not defined

If defined, enable breathing animation mode.

RGBLIGHT_EFFECT_RAINBOW_MOOD

Not defined

If defined, enable rainbow mood animation mode.

RGBLIGHT_EFFECT_RAINBOW_SWIRL

Not defined

If defined, enable rainbow swirl animation mode.

RGBLIGHT_EFFECT_SNAKE

Not defined

If defined, enable snake animation mode.

RGBLIGHT_EFFECT_KNIGHT

Not defined

If defined, enable knight animation mode.

RGBLIGHT_EFFECT_CHRISTMAS

Not defined

If defined, enable christmas animation mode.

RGBLIGHT_EFFECT_STATIC_GRADIENT

Not defined

If defined, enable static gradient mode.

RGBLIGHT_EFFECT_RGB_TEST

Not defined

If defined, enable RGB test animation mode.

RGBLIGHT_EFFECT_ALTERNATING

Not defined

If defined, enable alternating animation mode.

RGBLIGHT_ANIMATIONS

Not defined

If defined, enables all additional animation modes

RGBLIGHT_EFFECT_BREATHE_CENTER

1.85

Used to calculate the curve for the breathing animation. Valid values are 1.0 to 2.7

RGBLIGHT_EFFECT_BREATHE_MAX

255

The maximum brightness for the breathing mode. Valid values are 1 to 255

RGBLIGHT_EFFECT_SNAKE_LENGTH

4

The number of LEDs to light up for the "Snake" animation

RGBLIGHT_EFFECT_KNIGHT_LENGTH

3

The number of LEDs to light up for the "Knight" animation

RGBLIGHT_EFFECT_KNIGHT_OFFSET

0

The number of LEDs to start the "Knight" animation from the start of the strip by

RGBLIGHT_EFFECT_KNIGHT_LED_NUM

RGBLED_NUM

The number of LEDs to have the "Knight" animation travel

RGBLIGHT_EFFECT_CHRISTMAS_INTERVAL

1000

How long to wait between light changes for the "Christmas" animation, in milliseconds

RGBLIGHT_EFFECT_CHRISTMAS_STEP

2

The number of LEDs to group the red/green colors by for the "Christmas" animation

RGBLIGHT_RAINBOW_SWIRL_RANGE

360

Range adjustment for the rainbow swirl effect to get different swirls

You can also modify the speeds that the different modes animate at:

// How long (in milliseconds) to wait between animation steps for each of the "Solid color breathing" animations
const uint8_t RGBLED_BREATHING_INTERVALS[] PROGMEM = {30, 20, 10, 5};
// How long (in milliseconds) to wait between animation steps for each of the "Cycling rainbow" animations
const uint8_t RGBLED_RAINBOW_MOOD_INTERVALS[] PROGMEM = {120, 60, 30};
// How long (in milliseconds) to wait between animation steps for each of the "Swirling rainbow" animations
const uint8_t RGBLED_RAINBOW_SWIRL_INTERVALS[] PROGMEM = {100, 50, 20};
// How long (in milliseconds) to wait between animation steps for each of the "Snake" animations
const uint8_t RGBLED_SNAKE_INTERVALS[] PROGMEM = {100, 50, 20};
// How long (in milliseconds) to wait between animation steps for each of the "Knight" animations
const uint8_t RGBLED_KNIGHT_INTERVALS[] PROGMEM = {127, 63, 31};
// These control which hues are selected for each of the "Static gradient" modes
const uint16_t RGBLED_GRADIENT_RANGES[] PROGMEM = {360, 240, 180, 120, 90};

Functions

If you need to change your RGB lighting in code, for example in a macro to change the color whenever you switch layers, QMK provides a set of functions to assist you. See rgblight.h for the full list, but the most commonly used functions include:

Function

Description

rgblight_enable()

Turn LEDs on, based on their previous state

rgblight_enable_noeeprom()

Turn LEDs on, based on their previous state (not written to EEPROM)

rgblight_disable()

Turn LEDs off

rgblight_disable_noeeprom()

Turn LEDs off (not written to EEPROM)

rgblight_mode(x)

Set the mode, if RGB animations are enabled

rgblight_mode_noeeprom(x)

Set the mode, if RGB animations are enabled (not written to EEPROM)

rgblight_setrgb(r, g, b)

Set all LEDs to the given RGB value where r/g/b are between 0 and 255 (not written to EEPROM)

rgblight_setrgb_at(r, g, b, led)

Set a single LED to the given RGB value, where r/g/b are between 0 and 255 and led is between 0 and RGBLED_NUM (not written to EEPROM)

rgblight_setrgb_range(r, g, b, start, end)

Set a continuous range of LEDs to the given RGB value, where r/g/b are between 0 and 255 and start(included) and stop(excluded) are between 0 and RGBLED_NUM (not written to EEPROM)

rgblight_setrgb_master(r, g, b)

Set the LEDs on the master side to the given RGB value, where r/g/b are between 0 and 255 (not written to EEPROM)

rgblight_setrgb_slave(r, g, b)

Set the LEDs on the slave side to the given RGB value, where r/g/b are between 0 and 255 (not written to EEPROM)

rgblight_sethsv(h, s, v)

Set all LEDs to the given HSV value where h is between 0 and 360 and s/v are between 0 and 255

rgblight_sethsv_noeeprom(h, s, v)

Set all LEDs to the given HSV value where h is between 0 and 360 and s/v are between 0 and 255 (not written to EEPROM)

rgblight_sethsv_at(h, s, v, led)

Set a single LED to the given HSV value, where h is between 0 and 360, s/v are between 0 and 255, and led is between 0 and RGBLED_NUM (not written to EEPROM)

rgblight_sethsv_range(h, s, v, start, end)

Set a continuous range of LEDs to the given HSV value, where h is between 0 and 360, s/v are between 0 and 255, and start(included) and stop(excluded) are between 0 and RGBLED_NUM (not written to EEPROM)

rgblight_sethsv_master(h, s, v)

Set the LEDs on the master side to the given HSV value, where h is between 0 and 360, s/v are between 0 and 255 (not written to EEPROM)

rgblight_sethsv_slave(h, s, v)

Set the LEDs on the slave side to the given HSV value, where h is between 0 and 360, s/v are between 0 and 255 (not written to EEPROM)

rgblight_toggle()

Toggle all LEDs between on and off

rgblight_toggle_noeeprom()

Toggle all LEDs between on and off (not written to EEPROM)

rgblight_step()

Change the mode to the next RGB animation in the list of enabled RGB animations

rgblight_step_noeeprom()

Change the mode to the next RGB animation in the list of enabled RGB animations (not written to EEPROM)

rgblight_step_reverse()

Change the mode to the previous RGB animation in the list of enabled RGB animations

rgblight_step_reverse_noeeprom()

Change the mode to the previous RGB animation in the list of enabled RGB animations (not written to EEPROM)

rgblight_increase_hue()

Increase the hue for all LEDs. This wraps around at maximum hue

rgblight_increase_hue_noeeprom()

Increase the hue for all LEDs. This wraps around at maximum hue (not written to EEPROM)

rgblight_decrease_hue()

Decrease the hue for all LEDs. This wraps around at minimum hue

rgblight_decrease_hue_noeeprom()

Decrease the hue for all LEDs. This wraps around at minimum hue (not written to EEPROM)

rgblight_increase_sat()

Increase the saturation for all LEDs. This wraps around at maximum saturation

rgblight_increase_sat_noeeprom()

Increase the saturation for all LEDs. This wraps around at maximum saturation (not written to EEPROM)

rgblight_decrease_sat()

Decrease the saturation for all LEDs. This wraps around at minimum saturation

rgblight_decrease_sat_noeeprom()

Decrease the saturation for all LEDs. This wraps around at minimum saturation (not written to EEPROM)

rgblight_increase_val()

Increase the value for all LEDs. This wraps around at maximum value

rgblight_increase_val_noeeprom()

Increase the value for all LEDs. This wraps around at maximum value (not written to EEPROM)

rgblight_decrease_val()

Decrease the value for all LEDs. This wraps around at minimum value

rgblight_decrease_val_noeeprom()

Decrease the value for all LEDs. This wraps around at minimum value (not written to EEPROM)

Additionally, rgblight_list.h defines several predefined shortcuts for various colors. Feel free to add to this list!

Hardware Modification

If your keyboard lacks onboard underglow LEDs, you may often be able to solder on an RGB LED strip yourself. You will need to find an unused pin to wire to the data pin of your LED strip. Some keyboards may break out unused pins from the MCU to make soldering easier. The other two pins, VCC and GND, must also be connected to the appropriate power pins.