STM32 library for WS28xx LED control.

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👋 Introduction

Features

• WS281x led control
• HSV to RGB and RGB to HSV
• Filling and Clearing
• Brightness control

Compatibility with Boards

Currently, the library is tested on STM32F4 and STM32H7 microcontrollers, but there's a good chance it will be compatible with other STM32 microcontrollers.

Compatibility with LEDs

The library has been tested with WS2815 and WS2812 LEDs. It is highly likely to also work with WS2813 and WS2812B, or similar variants. It might not work with WS2811 LEDs.

Performance

In testing, the library demonstrated a refresh rate of approximately 19.5 LEDs per millisecond.

⚙️ Required Settings

Clock Configuration

Example clock config screenshot

(click to zoom)

SPI Settings

Enable SPI you want and set settings to:

These are tested settings, I encourage you to experiment with them.

The Baud Rate is the important setting for Clock.

SPI Settings Screenshot

🔌 Connection

Connect the strip control pin to the pin described as SPIx_MOSI in the pinout view.

💽 Installation

To install simply choose version for your CPU and insert the library among your other program files. Also install the files from the color folder.

🖥️ Basic Usage

Making Object

To use this library, create an object of the class strip from the swietlib namespace:

swietlib::strip ledstrip(&hspi2, 120);

Replace &hspi2 with a reference to the SPI handler you have chosen. (Remember to include spi.h)

Changing LED Color

Set LEDs color with this:

ledstrip.setPixel(10, swietlib::rgbColor(255, 128, 0));

or

ledstrip.setPixel(10, 255, 128, 0);

First argument means which LED in turn to change color,

Filling, Clearing

To clear the strip use:

ledstrip.clear();

To fill all the strip use:

ledstrip.fill(255, 128, 0);

Refreshing

To refresh strip (send data to strip) you need to use:

ledstrip.refresh();

More info you can find there.

💡 Examples

Rainbow

Simple moving rainbow effect using this library.

#include <cstdint>
#include "swietlib.hpp"
#include "swietlibColor.hpp"
#include "stm32f4xx.h"
#include "spi.h"

#define LED_COUNT 120

...

swietlib::strip ledstrip(&hspi2, LED_COUNT);

// Change it to modify the density of the rainbow                              ↓↓↓
for (uint16_t hue = 0, i = 0; i <= LED_COUNT; i++, hue += (65535 / (LED_COUNT / 2))) {
    ledstrip.setPixel(i, swietlib::hsvColor(hue, 255, 255).toRGB());
}

ledstrip.setBrightness(64);

uint16_t offset = 1;
while (1) {
    ledstrip.refreshOffset(offset);
    HAL_Delay(20);
    if (offset >= LED_COUNT) offset = 0;
    offset++;
}