PI4J LedStrip

[livansilvagarcia]

Hello everyone, I am testing Pi4j on a Pi Zero 2 W board, but the led strip is not working. I am using version 2.6 of Pi4j. I have imported all the classes from the components package in my project.

This is the code

public class AC_1 {

public static void main(String[] args) throws InterruptedException {
    
    System.out.println("LED strip app started ...");

    Context pi4j = Pi4J.newAutoContext();

    // Initialize the strip
    Duration ms50 = Duration.ofMillis(50);
    Duration ms500 = Duration.ofMillis(500);
    Duration sec1 = Duration.ofSeconds(1);

    int leds = 10;
    final LedStrip ledStrip = new LedStrip(pi4j, leds);

    Thread.sleep(1000);

    Index.getInstance().setVisible(true);

    while (true) {

        System.out.println("LED strip shines purple");
        Index.getInstance().upDateView("LED strip shines purple");
        ledStrip.setStripColor(LedStrip.LedColor.PURPLE);
        ledStrip.render(sec1);

        System.out.println("turn strip off");
        Index.getInstance().upDateView("turn strip off");
        ledStrip.allOff();
        ledStrip.render(sec1);

        System.out.println("toggle between GREEN and RED");
        Index.getInstance().upDateView("toggle between GREEN and RED");
        ledStrip.alternate(LedStrip.LedColor.GREEN, LedStrip.LedColor.RED, ms500, 3);

        System.out.println("setting the LEDs to blue and the first one to purple");
        Index.getInstance().upDateView("setting the LEDs to blue and the first one to purple");
        ledStrip.setStripColor(LedStrip.LedColor.BLUE);
        ledStrip.setPixelColor(0, LedStrip.LedColor.PURPLE);
        ledStrip.render(ms500);

        System.out.println("Start a kind of animation");
        Index.getInstance().upDateView("Start a kind of animation");
        for (int i = 0; i < leds - 1; i++) {
            ledStrip.setPixelColor(i, LedStrip.LedColor.BLUE);
            ledStrip.setPixelColor(i + 1, LedStrip.LedColor.PURPLE);
            ledStrip.render(ms50);
        }

        for (int i = leds - 1; i > 0; i--) {
            ledStrip.setPixelColor(i, LedStrip.LedColor.BLUE);
            ledStrip.setPixelColor(i - 1, LedStrip.LedColor.PURPLE);
            ledStrip.render(ms50);
        }

        Thread.sleep(100);

        System.out.println("setting the brightness to full and show the first LED as white");
        Index.getInstance().upDateView("setting the brightness to full and show the first LED as white");
        ledStrip.allOff();
        ledStrip.setMaxBrightness(1);
        ledStrip.setPixelColor(0, LedStrip.LedColor.WHITE);
        ledStrip.render(Duration.ofSeconds(2));

        //finishing and closing
        ledStrip.reset();

        System.out.println("LED strip demo finished.");
        Index.getInstance().upDateView("LED strip demo finished.");
    }

}

}

[FDelporte]

Hi, LED strips are a very hard component to control from a Linux-based system because of the exact timing that is required to control these. Did you take this remarks in the original code into account?
https://github.com/Pi4J/pi4j-example-components/blob/main/src/main/java/com/pi4j/catalog/components/LedStrip.java#L13

A better approach is to use an external device that is easier to communicate with, e.g. the Pixelblaze via serial communication, as described here: https://www.pi4j.com/examples/jbang/pixelblaze_output_expander/