While the first time around when we had to mill boards, we didn't really have to touch the actual circuit design itself. This week served as the first step towards that, by intro'ing us to the circuit cad programs, like Eagle.
The assignment was to take the original HelloWorld board, "reverse-engineer it" (make an Eagle version), add a button and an led, mill it, and stuff it. Above is my rendition of the board with my modifications, using Eagle. I'd used the program once or twice before so it wasn't too bad, most of the quirks are just bad UI design rather than real complexity.
The real challenge here was doing the trace routing. (We weren't allowed to auto-trace) In my first draft, I got pretty far along connecting everything together, even over-using the miter button like crazy once I found it, but I got completely stuck on the very last two pieces to connect. After being unable to see any way to fix this without huge refactoring I started over.
This time around, I decided to make two big changes: (1) Make the board double-sided and (2) beligerently use the circle button I just discovered. I'm pretty sure I went way overboard but it actually made things go way smoother and faster since all the IC's pins were basically universally accessible.
Unfortunately, due to a mix of planned and surprise projects in the past week, I didn't get a chance to get to the mill while it was both free and during sane (safe) hours. I'll post updates asap.