Infinite capacitance…

…for screwing up πŸ™‚

Ok, been struggling with this for a couple of days in a WTF! kind of way.

Have bunged in lots of capacitors. Nope. Don’t work.

Changed the main ATmega328 this morning.

Nope. Don’t make no difference πŸ™

Right, job be jobbed, I think. I can now run the motors at any speed without it crashing. Has to be a result. I do wish I understood this better but I’m having this as a “fact” for now – maybe the previous 2 “revisions” of this project would have worked if I tried this before. Dunno. Don’t really like “dunno” since it isn’t an answer.

Here’s where I got to before “testing”
IMG_20130127_200358

So, we add 0.1uF caps across the motor leads

IMG_20130129_215726

Seemed to help, but everything still crapping out frequently when the motor speed got up to nothing like “11”

I learned that you get a better effect by adding “moar caps” from motor leads to metal thingies

IMG_20130201_200824

Nope. It was better but not much better πŸ™

On the verge of giving up, I recalled some stuff I read about resistors on the I2C bus. Not sure I understand what I seem to remember but I had a play – starting point was 4K7. Tried 3K5 and it was much more stable. Have since tried 2K2 and it just, er, works πŸ™‚

So, my problems have been (I surmise) due to noise on the I2C bus – I hope all the caps I’ve thrown at this in the hope that something “sticks” have helped. Don’t really care. It works! W00t!

IMG_20130201_204032

Need to de-solder the 4K7 resistors and replace them with the 2K2 ones. Shouldn’t be too hard. “De-solder” may involve a bit of brutality with some wire snippers πŸ™‚

Happy days!

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