Our resident AVR/electronics expert Cameron, has been spending the last few weeks refining the circuit diagrams and patiently dealing with my lack of experience with a project of this size and complexity. Our conversations often go like this:

Jeremy: Look, I made a thing!

Cameron: Cool! I noticed <xyz>. Did you consider <abc>? You should really never do <123>...

Jeremy: *head explodes a little*

Cameron: *more experience tested advice*

Jeremy: *head expanding with knowledge...then asks stupid question*

Cameron: *patient reply*

Jeremy: *feeling smarter for knowing new things*

So for the past few weeks he's been doing double duty: finishing up the circuit board design and providing me with direction on the firmware and capacitive sensor programming.

After all that, we have very good news, we have ordered our first run of circuit boards! This run of boards will have extra circuitry that, hopefully, we won't need in the production run. We've been trying to figure out if the Atmega will be able to reliably handle the capacitive sensing or if we'll need to use a specialized chip (Azoteq IQS211).

The de facto Arduino capacitive sensing library blocks the execution of the main program while it's reading sensor data. This will significatly slow down how fast the nodes on the network will be able to communicate with the master. So we've added pads to the PCB for the specialized Azoteq chip, just in case. The good news is that the latest capacitive sensor libraries we've been writing are working really well. So I'm confident the next board will be much simpler.