i’ve backed it up, but the forum says .bin files aren’t allowed to upload within the thread, so, here it is: mw-20 bin
I tried your bin file on my board, and I saw no jitter.
That pretty much means that whatever is causing the issue, is not software.
Okay, so then my first question is are you powering with 3.7v or 7.4v? I’ve adjusted Arduino settings to no avail, but I could run that detailed diagnostic define like we did when trying to solve the issues with color display. Do you think there is something that would clue us in there?
If it’s a hardware issue, what is it about your MG995 that is better than these MG90S and FS90R servos? Some amount of power filtering on the little PCBs inside the motor? What could I look up, spec-wise to buy a better servo? Or could there be some amount of extra components to filter power, e.g. capacitor and/or resistor from some pad to ground?
Proffieboards cannot be powered with 7.4 volts.
I’m using a power supply rather than a battery though. It’s currently set for 4.1 volts.
Unfortunately that’s just going to tell us what the software is doing, but the problem isn’t with the software. It’s either the wiring, or with the proffieboard itself.
I think it has to be at this point.
I don’t actually think that is the issue here. I have tried a couple of different servos, some which are very cheap, and I’ve also looked at the signal using a logic analyzer. The signal looks clean and stable, which is why there is no jitter. (Of course, I could be wrong, maybe my servos are better, but I don’t know why that would be, I don’t have buy-the-right-servo superpowers.)
What I think is happening is that your board is generating a bad signal for some reason. I’m not sure why that would be, but the first step would be to check if that is true or not. That means hooking your board up to a logic analyzer or an oscilloscope and watch the output. Fortunately it doesn’t have to be a good logic analyzer, and bad ones can be had for less than $10 on amazon. (It’s also possible to rig one up from an Arduino or something.)
Out of curiosity, where did you get the board?
I appreciate your diligence in these responses, btw. I usually get my boards from Tritium or KR, but I recently got these from SaberBay because Tritium only had white (which I did also get, but that’s besides the point). So, chances are they could be aliexpress boards.
I think, based on your response to hkwinger in the original thread I replied to, that because yours are digital, and they read at 300hz (6x the analog rate), that perhaps that in and of itself is a form of signal filtering. So, I bought some SG90 servos (180° digital) you said you had tested, as well as some MG90D (360° continuous digital) servos. That way we’re still in the same sizes and functionality I’ve already learned how to program for. If those give me similar results, I’ll switch to a new board.
Will update in a few days. Thanks as always, @profezzorn
I was too impatient. I rewired a new board because “why not?” Works flawlessly. Definitely the other board sending bad signal. Thanks for all the input, @profezzorn.
I’m still going to potentially try the newer servos before finalizing this blaster build, but thought it helpful for other folks following the thread to know some Proffies are sending subpar signals, and to try another or get them from more reputable sources before giving up on your builds.
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