Wiring and config check

I must have something wrong because after flashing I get nothing. Serial monitor shows very low volts on the batters (between .66 and 1.7) But the same battery is over 4 volts in a different saber. So I know that battery is good. Looking for some help.

Config and marked up wiring diagram are attached. NPXL V3 connector wired independent from the blade. Single pixel crystal chamber. What have I done wrong?

Did you make sure to select “proffieboard v2” in Arduino->Tools->Board before you did the upload?

Yes. Upload works. No issues there. After the upload, though. The saber doesn’t work and the voltage shows really low. I put the same board into another different saber with a much simpler install and it works just fine. Before I try this again with a different board, I just want to make sure I’ve got everything correct.


That doesn’t answer my question, because if you select “proffieboard” instead of “proffieboard v2” uplod still works, but the board will not.

Sorry. Yes it is set to V2.

So, if the board is configured correctly, the next step is to check the wiring.
Have you measured the voltage at BATT+ / BATT- at the board with a multimeter?
Also, maybe you can post some pictures of the actual wiring?
It’s also possible that there is something wrong with the board itself, but usually the easiest way to detect that is to rule out everything else…

Here’s where I’m at. I put the board into a different saber with a much simpler setup and it works fine. I’m going to leave it there. I’ll wire this back up with a different board go from there. I was just making sure my wiring and config looked ok before I attempted it again.

If what I have planned looks ok. I’ll give it another go tonight and see what happens.


Ok. I haven’t seen anything obviously wrong with your plans so far.

New board, same problem. Here are some photos of my wiring. Any insight to my issue would be greatly appreciated.

Thank you.

I don’t see anything overly concerning in these pictures. The wiring looks reasonable. Have you measured the voltage at BATT+ / BATT- at the board with a multimeter? Have you tried a different battery?

Several different batteries.

Just put a multimeter to the pos and neg pads on the board and I get nothing. So I assume that tells me that there is an issue in the wiring. I just need to find it now. Most likely culprit being the positive leads.


What should I infer if when I put the multimeter on both battery contacts (in the chassis) and get no reading. But if I contact the neg contact and then touch the positive terminal on the battery, I get 4 volts. This is clearly an issue on the positive lead, correct?

I found it. The positive terminal is not contacting the positive battery tab. This is a chassis design flaw.

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Unfortunately 18650 batteries are not quite standardized in how much the positive “button” should stick out, or exactly how tall the batteries should be, which can cause these sort of issues. A different battery might work better, or you might be able to bend the battery terminal to make it work.

After talking to the chassis designer, he designs the chassis to have the positive at the speaker end. So, I was putting the positive contact in the space designed for the spring side. I’m fixing everything now.

Thanks for your help!

I have had success just blobbing nice rounded dollop of solder on the contact button. Although, a flat surface would be better for more contact.

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