Leds

class ev3dev2.led.Led(name_pattern='*', name_exact=False, desc=None, **kwargs)

Any device controlled by the generic LED driver. See https://www.kernel.org/doc/Documentation/leds/leds-class.txt for more details.

max_brightness

Returns the maximum allowable brightness value.

brightness

Sets the brightness level. Possible values are from 0 to max_brightness.

triggers

Returns a list of available triggers.

trigger

Sets the LED trigger. A trigger is a kernel based source of LED events. Triggers can either be simple or complex. A simple trigger isn’t configurable and is designed to slot into existing subsystems with minimal additional code. Examples are the ide-disk and nand-disk triggers.

Complex triggers whilst available to all LEDs have LED specific parameters and work on a per LED basis. The timer trigger is an example. The timer trigger will periodically change the LED brightness between 0 and the current brightness setting. The on and off time can be specified via delay_{on,off} attributes in milliseconds. You can change the brightness value of a LED independently of the timer trigger. However, if you set the brightness value to 0 it will also disable the timer trigger.

delay_on

The timer trigger will periodically change the LED brightness between 0 and the current brightness setting. The on time can be specified via delay_on attribute in milliseconds.

delay_off

The timer trigger will periodically change the LED brightness between 0 and the current brightness setting. The off time can be specified via delay_off attribute in milliseconds.

brightness_pct

Returns LED brightness as a fraction of max_brightness

class ev3dev2.led.Leds
set_color(group, color, pct=1)

Sets brightness of LEDs in the given group to the values specified in color tuple. When percentage is specified, brightness of each LED is reduced proportionally.

Example:

my_leds = Leds()
my_leds.set_color('LEFT', 'AMBER')

With a custom color:

my_leds = Leds()
my_leds.set_color('LEFT', (0.5, 0.3))
set(group, **kwargs)

Set attributes for each LED in group.

Example:

my_leds = Leds()
my_leds.set_color('LEFT', brightness_pct=0.5, trigger='timer')
all_off()

Turn all LEDs off

reset()

Put all LEDs back to their default color

animate_stop()

Signal the current animation thread to exit and wait for it to exit

animate_police_lights(color1, color2, group1='LEFT', group2='RIGHT', sleeptime=0.5, duration=5, block=True)

Cycle the group1 and group2 LEDs between color1 and color2 to give the effect of police lights. Alternate the group1 and group2 LEDs every sleeptime seconds.

Animate for duration seconds. If duration is None animate for forever.

Example:

from ev3dev2.led import Leds
leds = Leds()
leds.animate_police_lights('RED', 'GREEN', sleeptime=0.75, duration=10)
animate_flash(color, groups=('LEFT', 'RIGHT'), sleeptime=0.5, duration=5, block=True)

Turn all LEDs in groups off/on to color every sleeptime seconds

Animate for duration seconds. If duration is None animate for forever.

Example:

from ev3dev2.led import Leds
leds = Leds()
leds.animate_flash('AMBER', sleeptime=0.75, duration=10)
animate_cycle(colors, groups=('LEFT', 'RIGHT'), sleeptime=0.5, duration=5, block=True)

Cycle groups LEDs through colors. Do this in a loop where we display each color for sleeptime seconds.

Animate for duration seconds. If duration is None animate for forever.

Example:

from ev3dev2.led import Leds
leds = Leds()
leds.animate_cyle(('RED', 'GREEN', 'AMBER'))
animate_rainbow(group1='LEFT', group2='RIGHT', increment_by=0.1, sleeptime=0.1, duration=5, block=True)

Gradually fade from one color to the next

Animate for duration seconds. If duration is None animate for forever.

Example:

from ev3dev2.led import Leds
leds = Leds()
leds.animate_rainbow()

LED group and color names

EV3 platform

Led groups:

  • LEFT
  • RIGHT

Colors:

  • BLACK
  • RED
  • GREEN
  • AMBER
  • ORANGE
  • YELLOW

BrickPI platform

Led groups:

  • LED1
  • LED2

Colors:

  • BLACK
  • BLUE

BrickPI3 platform

Led groups:

  • LED

Colors:

  • BLACK
  • BLUE

PiStorms platform

Led groups:

  • LEFT
  • RIGHT

Colors:

  • BLACK
  • RED
  • GREEN
  • BLUE
  • YELLOW
  • CYAN
  • MAGENTA

EVB platform

None.