The Frustromantic Box, Part 3: Electronics

In this series’ third post I describe the electronics involved in the Frustromantic Box.

The electronics involved in the Frustromantic Box are pretty straightforward.  I hooked everything up on a SparkFun Protoshield based on the instructions here, which I think are slightly out of date now.  I think the attached block diagram explains everything pretty clearly, but here’s a bit more detail: apart from the Arduino’s I/O pins, the connections form two power planes and a ground plane.  The 6V output of the Polulu switch runs the Arduino (which I guess regulates it to 5V), the servos and the illuminated switch.  The 5V output of the Arduino powers the LCD display, the GPS module and the IR receiver.

The block diagram doesn’t show the power supply.  I used 4xAA’s, which hook up to the GND and VIN pins on the Polulu switch.

I had a real problem processing the output of the PNA4612 module when the batteries are even slightly discharged.  This might be something I could correct in software, but if I were doing it again, I’d probably just run a barrel jack through the side of the box, similar to what Mikal did on the original puzzle box.

By the time I got the electronics finished up, I was running out of time before Christmas.  Rather than solder everything to the prototype board, I just left it on the solderless breadboard and epoxied the $*#% out of it.

Continue to Part 4: Software