keychron_qmk_firmware/docs/feature_rgblight.md

RGB Lighting

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.

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.

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

?> For backwards compatibility, RGB_SMOD is another alias of RGB_MOD.

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_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)

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.