PCA9685 control

[tumbleweed]

Would there be anything to gain if the code in the SetPCA: section above is placed in the check section like this

It'll save you the call/return (so slightly less time/code), but it won't really change the timing much in the grand scheme of things.

If the flicker is caused by writing too often to the PCA it won't change that at all.

[Scampy]

I took delivery of a logic analyser today and thought I would test it to see what the outputs are like at different brightnesses. I've got some really strange traces and wondered if anyone has any ideas as to why the PCA chip is behaving like this.

I set the brightness to 10%, and did a scan and this was the result



I was expecting to see eight traces the same as channel 7 at the bottom, but the other channels seems to have a strange artefact, so I zoomed in to see if it was just something to do with the way the traces were being displayed on the screen, but this was the result



The "normal" pulse was itself split up into a series of multiple pulses, so I zoomed in again and took a measurement



I have no idea what's happening, and I still can't find any evidence of the chip refreshing momentarily once a second which would tie in with the regular 1sec flicker that is noticeable to the eye

[Scampy]

I think I've sorted it... possible ground loop, removed the GND wires between the LA and breadboard and now all seems fine