HD Active V2 Wiring/External Power Help

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I’m using a RPi Zero 2W and either a 64x64 or two 128x64 matrices (ran as 128x128 with vmap on the adafruit hat). Both of these setups work with the Adafruit Bonnet, but only when I supply the 5v power to the bonnet. If I supply power directly to the matrix (and power over USB to the Pi), Demo 0 results in red lines flashing all over instead of behaving like normal.
I’m using this female DC adapter from adafruit when supplying the power directly.

I’m looking for help with two things:
Firstly I’d love help diagnosing why the matrix misbehaves when directly supplied with power, especially since it works flawlessly when the power supply is plugged directly into the adafruit bonnet.

Secondly, I’m not entirely sure how to supply power directly to the hardwaredragon adapter - I soldered the supplied 8.5mm connectors and used the above mentioned female DC adapter (and some extra wire I had) to supply power to the board, but my Pi isn’t lighting up when I do that. Are there any additional steps I need to take for the adapter to supply power to the Pi?

Thanks! I can provide photos of any connectors etc. as well if that would be helpful.

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If you provide USB power, it is probably amp limited and causes your powers to be starved of power and glitch.
You definitely should power the panels 5V directly, not through USB. It can be made to work with some USB power supplies, I have one running right now, but it’s error prone and not recommended.

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Thanks! To be clear, I’m powering only the Pi via USB, and the panels via their own 5v power supply (specifically this one, as I’m driving a 128x128 display). Here are some photos of the setup with the electrodragon adapter:

IMG_9564.HEIC
IMG_9564.HEIC3024×4032 3.26 MB

IMG_9565.HEIC
IMG_9565.HEIC3024×4032 1.92 MB

4

Of course, as soon as I posted this reply I retried the setup with a better wall adapter for the RPi usb power, and it works. Ultimately it would be ideal if I could power the RPi from the electrodragon board, but I can’t seem to get that to work right now (if I wire the 5v from the power supply to the board, the pi doesn’t even turn on).

1 Like
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Yeah, the Pi really wants proper 5V with enough amps, and lots of 5V USB power supplies are not sufficient.