Inspired by the Python-friendly cyber:bot (which I just received -- thank you, Parallax), I have been wondering about using the Parallax Shield-Bot with Adafruit's METRO M0 Express
, which can be programmed in CircuitPython (Adafruit's beginner-oriented flavor of MicroPython). The M0 has (almost) the same form factor as the Arduino Uno, but it operates at 3.3V logic levels rather than 5V.
At first, I assumed the voltage difference would be a big problem, but then I examined the schematic for the Shield-Bot
and now I think using the M0 with the Shield-Bot might be quite feasible. It appears that power is regulated by the Uno/M0 board, and the shield merely "brings it up" for the servos and breadboard. Looks like Vin from the Uno/M0 feeds the Shield's VR1 and VR2 regulators, and they just output to the X1 headers to power the breadboard. In other words, so long as I am careful not to (directly or indirectly) connect a 5V or Vin power pin to one of the M0's I/O pins, then there should be no problem -- right? The continuous-rotation servos allow 3.3V as well as 5V control signals (IIRC, the Propeller boards use 3.3).
I am posting this here in case anyone has already attempted what I have proposed, or in case any of you sees something that I have missed that would cause the M0 to fail when used in conjunction with the Shield-Bot.