It is not for a daughter board to cpu. Is is an adapter to connect a radio board (module) that has a 2x6 male header on to a breadboard. On a PCB, that is just a 2x6 set of 0.1 inch spacing THT pads. It needs more than direct connection to the Arduino board, because it needs 3.3 volts, and the Arduino does not supply enough current. But to hook it (by it self) to a breadboard needs 12 wires. 2 cables (0.1in space headers each end) of 6 wires each works, but that is messy both physical and in the Fritzing breadboard view. I took 2 male/female headers, bent the legs out sideways then back down again. Those then sit nicely on the inner columns, across the centre divider of the breadboard, allowing the 2x6 male header to plug in. Nice and neat physically for (software) development and testing.
Creating a custom breadboard with 2 extra pins where the centre divide usually goes would work. There is no specific size of breadboard though, and no fixed position for it to go. This is aimed at people learning Arduino to external hardware interfacing. See the ARDX (Arduino Experimenters) Kit information for context. I am adding some extensions to the existing projects / experiments, and want to keep it flexible for people to play with.
Another thing that would work, is creating the part for the radio module with the adapter 'built-in'. That would then need doing separately for every else that had a 2xX maie header. I'm a programmer, and believe in DRY (Don't Repeat Yourself). A separate adapter is so much cleaner and more flexible.
Here is a version of the in progress part, with a 3D ish icon to show the piece layout.
2-by-x-header2breadboard.fzpz (2.9 KB)
I'm also exploring Fritzing part creation, and this looked like it should be simple, but use a few features I had not tried yet. The part files have all been created using an xml aware text editor, not the Parts Editor and/or Inkscape/Illustrator.
