PixelBlaze keeps crashing / disconnecting and turning off LEDs

I’m experiencing a bug I’ve never had before where upon giving power to my PixelBlaze (details below), it runs through a pattern as normal for roughly 3.5 seconds and then all of the LEDs turn off, and don’t come back on. Power cycling the PixelBlaze repeats this 3.5 seconds of success, followed by failure. When the LEDs are off, the PixelBlaze will still accept input / let me change the pattern / brightness / etc, but nothing happens to the LEDs.

Setup: PixelBlaze v3 updated to 3.51 with sensor expansion board attached but unused, connected to Micro-USB with a full 2.1a at the USB-A end, is connected to a strand of 353 25mm spacing pebble LEDs. Brightness is set to 20% maximum, and this was working fine for the first half hour or so of testing (no voltage drop, no flickering, no weirdness from that’s too many LEDs to drive from MicroUSB, everything was looking great).

I’ve tried using a pattern that’s EXTREMELY minimal power draw – the below snippet from the training tutorial which only has 3 LEDs lit at a time – and that didn’t change the observed behavior. I get the RGB three LEDs move along the line for a couple of seconds, the nothing.

In the web console, the status flashes from “connected” to “disconnected” and then back to “connected” when the LEDs turn off, indicating something is causing the PB to restart maybe?

I am confident I don’t have a short or wiring issue, because it WAS working for a half hour of testing prior to finding this issue, and when I swap over to a WLED board wired the exact same way I have lying around (I am running short on test PixelBlaze right now; I could take one out of another project) it works fine. And if it was a wiring issue (e.g. I swapped the ground and data lines or something) I wouldn’t get it working for the first 3.5 seconds. The PixelBlaze indicator LED stays a solid orange the whole time.

To prove I’m not just nuts, and because it’s a cool video, here’s what it was looking like BEFORE it stopped working for longer than 3.5 seconds at a time. I can’t think of anything I changed in between; I was just playing with patterns:

(This is a hat in the making)

export function render(index) {
  red = green = blue = 0
  leadPosition = time(0.08) * pixelCount
  red   = abs(leadPosition - index - 0) < 1
  green = abs(leadPosition - index - 4) < 1
  blue  = abs(leadPosition - index - 8) < 1
  rgb(red, green, blue)
}

@wizard this is probably a question for you?

It sounds like maybe the Auto Off schedule is set, and it’s turning the LEDs off as soon as it gets an internet connection and the time back from the discovery service.

If that’s not it, and you are seeing the wifi drop or a it is rebooting (watch the status LED), then I’d test:

  • With brightness set to zero
  • With LEDs physically disconnected
  • With another PB but using these LEDs and power supply
  • With a different power supply
  • Try updating/repairing the firmware in case thats corrupted somehow - can be done via /recovery tool.
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Thank you @wizard and I’m sorry for what turns out to be a straight user error. You were right. It was a PixelBlaze that had an auto-off timer because I used it to power a frontage sign at Burning Man and I completely forgot about that. I probably would have figured it out myself, except I happened to be working on the project RIGHT as the clock ticked over to “turn this board off for the day” mode, so it was working… and then it suddenly wasn’t.

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