Possible unsafe output range / DC offset when using EtherDream (hardware issue observed)

[yurigo]

Hello,

First of all, thank you for this library — I've been using it with the simulator and EtherDream and it works really well.
I've adquired a Laserworld DS-1000RGB MK5 + EtherDream (mostly recomended by this post: https://modulaser.app/guides/buy-a-laser). Thank you.

I’m reporting a potentially serious issue or at least asking for clarification about signal ranges and safety when using real hardware.

Setup

• Laser: Laserworld DS-1000RGB MK5
• DAC: EtherDream
• Library: @laser-dac/core, @laser-dac/ether-dream, @laser-dac/draw
• Mode tested:
  • Simulator → works as expected
  • EtherDream → caused hardware failure (details below)

Code

import dotenv from "dotenv";

import { DAC } from "@laser-dac/core";
import { Simulator } from "@laser-dac/simulator";
import { EtherDream } from "@laser-dac/ether-dream";
import { Scene, Line } from "@laser-dac/draw";

dotenv.config();

// wave.js – animated sine wave using Scene Line segments.
// A colour gradient sweeps along the wave as it scrolls in phase over time.

const dac = new DAC();

if (process.env.DEVICE === "EtherDream") {
  dac.use(new EtherDream());
}
else{
  dac.use(new Simulator());
}

const started = await dac.start();

if (!started) {
  console.error("Failed to start DAC");
  process.exit(1);
}

const scene = new Scene({ resolution: 70 });
const SEGMENTS = 50;
let phase = 0;

function renderFrame() {
  phase += 0.1;
  const stepX = 0.9 / SEGMENTS;

  for (let i = 0; i < SEGMENTS; i++) {
    const x1 = 0.05 + i * stepX;
    const x2 = x1 + stepX;
    const y1 = 0.5 + 0.4 * Math.sin(i * 0.4 + phase);
    const y2 = 0.5 + 0.4 * Math.sin((i + 1) * 0.4 + phase);
    const hue = (i / SEGMENTS + phase * 0.05) % 1;

    scene.add(
      new Line({
        from: { x: x1, y: y1 },
        to: { x: x2, y: y2 },
        color: [
          Math.abs(Math.sin(hue * Math.PI)),
          Math.abs(Math.sin(hue * Math.PI + (2 * Math.PI) / 3)),
          Math.abs(Math.sin(hue * Math.PI + (4 * Math.PI) / 3)),
        ],
      }),
    );
  }
}

scene.start(renderFrame);
dac.stream(scene);

---

Observed behavior (simulator)

This works fine on the simulator (.env -> DEVICE = Simulator).

Observed behavior (real hardware)

(.env -> DEVICE = EtherDream)

• Initially, the wave renders correctly
• After ~5 seconds:
  • the output starts drifting upwards (Y axis)
  • the beam moves towards the top edge
• Then:
  • the laser shuts down

After this event, the projector no longer starts correctly:

• X galvo moves during startup
• Y galvo remains unresponsive
• the system enters a restart loop (likely protection / "hiccup mode")

Important notes

• The same code behaves perfectly in the Simulator
• All coordinates are within [0, 1] as per documentation
• No obvious out-of-range values are being sent
• The issue appeared after only a few seconds of normal rendering

Why I'm reporting this

I'm not sure about the root cause. It could be:

• misuse or incorrect assumptions on my side (e.g. coordinate space or signal expectations)
• a hardware fault in the laser projector
• a limitation or behavior of the EtherDream DAC
• or a missing safeguard / validation in the library when targeting real hardware

However, since the simulator behaves correctly while the real hardware failed, I think it's worth clarifying expected signal ranges and safe usage patterns.

Thanks in advance, any guidance would be really helpful to avoid damaging hardware.

[SpaceK33z]

Hey, we recommend to use our new library: https://github.com/ModulaserApp/laser-dac-rs

Our Ether Dream implementation in this repository was never so high quality.