LIBBLINKY

This light library can be used to blink a digital LED following a custom pattern without using a timer or blocking code.

Note

This library does not actually blink the led directly but it manage its state internally

Usage

To use this library first declare a new Blinky handler and initialize it with the blinky_init function as follows:

Blinky blinker;
blinky_init(&blinker, pattern, PATTERN_SIZE, true, BLINKY_LOW);

The init function requires a pattern with its length, the option to repeat it or run it once and the initial state of the led.

To update the led status you need to call the blinky_routine function and set the actual led status accordingly as follows:

BlinkyState led_status = blinky_routine(&blinker, current_time);
set_led_status(led_status);

where the current_time is the time that the blinker library uses to check the led state and the set_led_status function has to be implemented by the user (or substituted with an equivalent function)

Note

The provided time defines the unit of measurement of the pattern (recomended is s or ms)

---

The pattern is an array of uint16_t where each element represent how much time the led should remain in the current state.
The initial state is set in the init function but can be changed any time.

If the difference between the current time and the previous saved time is greater than the time specified in the pattern at the current index the state is toggled and the index is incremented by one.

Note

If the bilnker is set to repeat mode the index wraps around after it reaches the end, otherwise it is just set to 0

For example with HIGH as initial state and the following pattern: { 500, 1000, 500 }; the led is kept HIGH for 500 units of time, then LOW for 1000 and then HIGH again for 500.
If the pattern repeats, the state is reset to the initial state so, in this example, after the led stays HIGH for 1000 units of time it stays *HIGH for another 1000.

Examples

Here is a complete example using an STM32 microcontroller with the HAL library:

#include <stdint.h>
#include <stdbool.h>
#include "blinky.h"

#define BLINKY_PATTERN_SIZE (4U)

Blinky blinker;
uint16_t pattern[BLINKY_PATTERN_SIZE] = {
    500,
    500,
    500,
    500
};

int main(void) {
    // Init blinker
    blinky_init(&blinker, pattern, BLINKY_PATTERN_SIZE, true, BLINKY_LOW);

    while (1) {
        // Run blinker and update the led
        BlinkyState led_status = blinky_routine(&blinker, HAL_GetTick());
        HAL_GPIO_WritePin(LED_GPIO_Port, LED_Pin, led_status);
        HAL_Delay(10); // Optional, not needed
    }
}