In putting together the code shield, there were several choices we made that warrant discussion. We’d welcome your feedback on these and will continue to improve the board as we move forward…
Board Layout
We decided to keep the board within the standard Arduino footprint. This means some of the components are a bit crowded. So far, this has not proven much of an issue, and seems like a worthwhile tradeoff to keep it small.
Filtering Circuits
We have encountered some minor functional issues that arise from using too many components at the same time. Mostly these affect the Arduino PWM outputs, and would probably improve if we added isolation caps, but we wanted to keep the design simple and understandable. As a learning tool, the philosophy is Keep It Simple, but maybe we went a bit far. We’ll continue with user testing to see if it become an issue.
Piezo Jumper
Many people have noted that R10 is a simple jumper and asked us why. The rationale for this is that if these are being used in a classroom, it may be valuable for a teacher to be able to lower the volume or disable the piezo altogether for the sake of the classroom noise level. To accomplish this, the R10 jumper may be replaced with a suitable resistor.