Even if I do say it myself, I’m getting pretty good at making printed circuit boards at home. Even down to adding a silk screen layer on top. Nearly everything I do is single sided though – and this can present a problem when it comes to docking with an Arduino.
Since the solder side is always on the back, you can’t use the standard shield trick of stacking upwards with the Arduino on the bottom, because the pins are going the wrong way.
So I came up with the…
I used the Arduino layout in the Adafruit Eagle library, and wired the pins as normal. Then when I switched to board layout I mirrored the Arduino component and completed the board.
After assembly you just flip the Arduino over and dock it upside down. Also you can mount the PCB to the case, so you’re not really limited to a standard shield size – you can make them as big as you need. As an added bonus you can just switch out one Arduino from project to project.
The only caveat is that if you use the space under the Arduino and install socketed chips, (or potentiometers, like I did) then you need to solder some double height pin headers to provide enough clearance.
I had a quick look around the web, and I haven’t seen anyone else doing this – so in the international patenting system of DIBS – I claim first dibs on it (or call “shotgun” if you’re living over here).
..till someone else can show me prior art.