Arduino-Blinkenlight

Supercharge your status-LEDs

This library gives you non-blocking blinking patterns and smooth fade effects for your LEDs, buzzers or any other status indicators

Features

On / off / toggle
Infinite blinking
Blink patterns (for example to blink an error code)
Single flashes and pauses, resuming the previous mode

Other goodies:

Completely non-blocking (no delay())
Super-nice fading effects (optional) with logarithmic brightness compensation for LEDs
Lightweight
All parameters can be adjusted on the fly without visual hickups
Easily extendable to control components via SPI / CAN / I2C / UART ...
Comes with good-looking defaults (at least I tried)
Tries to be user friendly (for example calling blink() while blinking does not
restart the cycle)
Supports active low (inverted) logic
Can be used for buzzers as well

Example

This example blinks the built-in LED on pin 13 in the following pattern:

#include <Blinkenlight.h>

Blinkenlight led(13);

void setup()
{
  led.pattern(2, 3);  // blink 2x, then 3x
}

void loop()
{
  led.update();
}

Note: If you'd love a smoother look, just use the Fadinglight-class instead of Blinkenlight. A Fadinglight has smooth fading effects with logarithmic LED brightness compensation. Your boards never looked more professional! /s

Installation

Platform.io

Blinkenlight is available in the platform.io registry

pio lib install "tfeldmann/Blinkenlight"

Arduino library manager

Blinkenlight is available in the Arduino library manager.

Full API

Instantiation

// Without fading effect:
#include <Blinkenlight.h>
Blinkenlight myLed(13);  // Blinkenlight(int pin, bool invert = false);

// With fading effect:
#include <Fadinglight.h>
Fadinglight myLed(13);  // Fadinglight(int pin, bool logarithmic = true, int fade_speed = 30);

// now in your code you can do:
myLed.off();
myLed.blink();
myLed.pattern(3, 5, SPEED_FAST);
// ... and so on (see below)

Basic usage (what you can do with your light)

// set permanently ON
void on();

// set permanently OFF
void off();

// toggle between on / off
void toggle();

// set ON / OFF permanently
void permanent(bool enable);

// blink infinitely
void blink();
void blink(SpeedSetting speed);

// blink `num` times, then long pause
// repeats, if `repeat` is set, OFF otherwise.
void pattern(int num, bool repeat = true);
void pattern(int num, SpeedSetting speed, bool repeat = true);

// blink `num1` times, short pause, blink `num2` times, long pause
// repeats, if `repeat` is set, OFF otherwise.
void pattern(int num1, int num2, bool repeat = true);
void pattern(int num1, int num2, SpeedSetting speed, bool repeat = true);

// turn ON for the given duration in ms. Continues in the previous mode afterwards.
void flash(uint16_t duration_ms);

// turn OFF for the given duration in ms. Continues in the previous mode afterwards.
void pause(uint16_t duration_ms);

// `true` if the Blinkenlight is currently blinking, showing a pattern, flashing or pausing
bool isOn();

// You must call this in your loop!
// Returns the current value of the light (LOW / HIGH).
// - You can ignore that if you want.
int update();

Blinking speed and timing parameters

// setup the timing parameters
void setSpeed(SpeedSetting setting);

// Available by default: SPEED_RAPID, SPEED_FAST, SPEED_SLOW
myLed.setSpeed(SPEED_RAPID);
myLed.setSpeed(SPEED_FAST);
myLed.setSpeed(SPEED_SLOW);

// .. or use your own settings. SpeedSetting is a struct:
typedef struct
{
    uint16_t on_ms;         // ON time in milliseconds
    uint16_t off_ms;        // OFF time in milliseconds
    uint16_t pause_ms;      // pause between `num1` and `num2` in pattern()
    uint16_t ending_ms;     // ending after a full pattern
} SpeedSetting;

// so you can set it up like this:

SpeedSetting mySettings = {
    .on_ms = 100,
    .off_ms = 100,
    .pause_ms = 2000,
    .ending_ms = 2000,
};

// ... alternatively you can setup the speed settings directly with this method
void setSpeed(
    uint16_t on_ms,
    uint16_t off_ms,
    uint16_t pause_ms,
    uint16_t ending_ms);

// ... or by providing a single value, the other values are inferred from that by
// some internal factors
void setSpeed(uint16_t on_ms);

// Hint: You can also modify the values directly - even on the fly - e.g.:
myLed.settings.on_ms = 250;
myLed.settings.pause_ms = 2000;

Fading effect and brightness compensation

LED brightness is not linear to the PWM value you set to the pin. This library uses a logarithmic dimming curve to create natural looking fading effects.

I have a status indicator controlled via CAN / I2C / SPI / ... What can I do?

No problem! You have two options.

Use the generic BaseBlinker class from <BaseBlinker.h>. The .update()-method returns a boolean whether the status is currently HIGH or LOW. You can then send this value to your status Blinkenlight (see examples/GenericBlink). Use the BaseFader class if you want fading effects. Here the update method returns an integer 0..255.
Subclass the BaseBlinker class with custom logic. This is what Blinkenlight does internally (see src/Blinkenlight.h). Have a look at the SerialBlink example!

Why

I created this library because I like to blink my error codes to the user. So for example blink two times, then three times for error 23 - you get the idea.

Over the time I found it super useful to handle basically all buzzers, lights and LEDs. I have multiple applications where it controls status lights via CAN.

Badges

Extracted from project README