kmk_firmware/docs/rgb.md

10 KiB

RGB/Underglow/Neopixel

Want your keyboard to shine? Add some lights!

Circuitpython

If not running KMKpython, this does require the neopixel library from Adafruit. This can be downloaded here. It is part of the Adafruit CircuitPython Bundle. Simply put this in the "root" of your circuitpython device. If unsure, it's the folder with main.py in it, and should be the first folder you see when you open the device.

Currently we support the following addressable LEDs:

  • WS2811, WS2812, WS2812B, WS2812C, etc.
  • SK6812, SK6812MINI, SK6805

Color Selection

KMK 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.

Enabling the extension

The only required values that you need to give the RGB extension would be the pixel pin, and the number of pixels/LED's. If using a split keyboard, this number is per side, and not the total of both sides.

from kmk.extensions.RGB import RGB
from kb import rgb_pixel_pin  # This can be imported or defined manually

rgb_ext = RGB(pixel_pin=rgb_pixel_pin, num_pixels=27)
keyboard.extensions.append(rgb_ext)

[Keycodes]

Key Aliases Description
KC.RGB_TOG Toggles RGB
KC.RGB_HUI Increase Hue
KC.RGB_HUD Decrease Hue
KC.RGB_SAI Increase Saturation
KC.RGB_SAD Decrease Saturation
KC.RGB_VAI Increase Value
KC.RGB_VAD Decrease Value
KC.RGB_ANI Increase animation speed
KC.RGB_AND Decrease animation speed
KC.RGB_MODE_PLAIN RGB_M_P Static RGB
KC.RGB_MODE_BREATHE RGB_M_B Breathing animation
KC.RGB_MODE_RAINBOW RGB_M_R Rainbow animation
KC.RGB_MODE_BREATHE_RAINBOW RGB_M_BR Breathing rainbow animation
KC.RGB_MODE_KNIGHT RGB_M_K Knightrider animation
KC.RGB_MODE_SWIRL RGB_M_S Swirl animation

Configuration

Define Default Description
keyboard.pixel_pin The pin connected to the data pin of the LEDs
keyboard.num_pixels The number of LEDs connected
keyboard.rgb_config['rgb_order'] (1, 0, 2) The order of the pixels R G B, and optionally white. Example(1, 0, 2, 3)
keyboard.rgb_config['hue_step'] 10 The number of steps to cycle through the hue by
keyboard.rgb_config['sat_step'] 17 The number of steps to change the saturation by
keyboard.rgb_config['val_step'] 17 The number of steps to change the brightness by
keyboard.rgb_config['hue_default'] 0 The default hue when the keyboard boots
keyboard.rgb_config['sat_default'] 100 The default saturation when the keyboard boots
keyboard.rgb_config['val_default'] 100 The default value (brightness) when the keyboard boots
keyboard.rgb_config['val_limit'] 255 The maximum brightness level

Built-in Animation Configuration

Define Default Description
keyboard.rgb_config['breathe_center'] 1.5 Used to calculate the curve for the breathing animation. Anywhere from 1.0 - 2.7 is valid
keyboard.rgb_config['knight_effect_length'] 4 The number of LEDs to light up for the "Knight" animation

Functions

If you want to create your own animations, or for example, change the lighting in a macro, or a layer switch, here are some functions that are available.

Function Description
keyboard.pixels.set_hsv_fill(hue, sat, val) Fills all LED's with HSV values
keyboard.pixels.set_hsv(hue, sat, val, index) Sets a single LED with HSV value
keyboard.pixels.set_rgb_fill((r, g, b)) Fills all LED's with RGB(W) values
keyboard.pixels.set_rgb((r, g, b), index) Set's a single LED with RGB(W) values
keyboard.pixels.disable_auto_write(bool) When True, disables showing changes. Good for setting multiple LED's before a visible update
keyboard.pixels.increase_hue(step) Increases hue by a given step
keyboard.pixels.decrease_hue(step) Decreases hue by a given step
keyboard.pixels.increase_sat(step) Increases saturation by a given step
keyboard.pixels.decrease_sat(step) Decreases saturation by a given step
keyboard.pixels.increase_val(step) Increases value (brightness) by a given step
keyboard.pixels.decrease_val(step) Decreases value (brightness) by a given step
keyboard.pixels.increase_ani() Increases animation speed by 1. Maximum 10
keyboard.pixels.decrease_ani() Decreases animation speed by 1. Minimum 10
keyboard.pixels.off() Turns all LED's off
keyboard.pixels.show() Displays all stored configuration for LED's. Useful with disable_auto_write explained below
keyboard.pixels.time_ms() Returns a time in ms since the board has booted. Useful for start/stop timers

Direct variable access

Define Default Description
keyboard.pixels.hue 0 Sets the hue from 0-360
keyboard.pixels.sat 100 Sets the saturation from 0-100
keyboard.pixels.val 80 Sets the brightness from 1-255
keyboard.pixels.reverse_animation False If true, some animations will run in reverse. Can be safely used in user animations
keyboard.pixels.animation_mode static This can be changed to any modes included, or to something custom for user animations. Any string is valid
keyboard.pixels.animation_speed 1 Increases animation speed of most animations. Recommended 1-5, Maximum 10.
from kmk.extensions.rgb import AnimationModes
rgb_ext = RGB(pixel_pin=rgb_pixel_pin,
        num_pixels=27
        num_pixels=0,
        val_limit=100,
        hue_default=0,
        sat_default=100,
        rgb_order=(1, 0, 2),  # GRB WS2812
        val_default=100,
        hue_step=5,
        sat_step=5,
        val_step=5,
        animation_speed=1,
        breathe_center=1,  # 1.0-2.7
        knight_effect_length=3,
        animation_mode=AnimationModes.STATIC,
        reverse_animation=False,
        )

Hardware Modification

To add RGB LED's to boards that don't support them directly, you will have to add a 3 wires. The power wire will run on 3.3v or 5v (depending on the LED), ground, and data pins will need added to an unused pin on your microcontroller unless your keyboard has specific solder points for them. With those 3 wires connected, set the pixel_pin as described above, and you are ready to use your RGB LED's/Neopixels.

Troubleshooting

Incorrect colors

If your colors are incorrect, check the pixel order of your specific LED's. Here are some common ones.

  • WS2811, WS2812, WS2812B, WS2812C are all GRB (1, 0, 2)
  • SK6812, SK6812MINI, SK6805 are all GRB (1, 0, 2)
  • Neopixels will vary depending on which one you buy. It will be listed on the product page.

Lights don't turn on

Make sure that your board supports LED backlight by checking for a line with PIXEL_PIN. If it does not, you can add it to your keymap. If you added the LED's yourself, you will also need to set num_pixels to the number of installed LED's in total.