For this week we must connect two (or more) boards togheter.
Because my final project need a network comunication, I made my boards for that goal.
The connection must be from analog imput (sound) from digital outputs (leds) naturally this com'plicated my life a bit.
However I wanted to made an "head" board with free pinheaders, to connect those with other boards without processor.

I made my board project with eagle.

Files here: Interiors and Board STL.

On the traces making I opted for the old method of "drawing with hands" that help me a lot in the begins of this process.
I've added two bridges (0 ohm resistors) to connect a difficult track.

When my file was ready I exported it, always with 1600 resolution. Than I made machine files with the FabModules.

Fab modules process:

Traces:

1- Set the machine type
2-Set the top size (1/64 for traces)

3- Select the machine model
4- Change all the safe to zero

5- Set the number of offsets (Five) 6- Calculate and export.

Boarder:

1- Set the top size (1/32 for the outline)

2- Set cut depth 0.6
3- Calculate and export.

On the machine program set "User coordinate system".

To have a better precision of the Z I use a paper.

On the first passage something gone wrong, and the mill donsn't worked properly, maybe caused by a distorction of the base.

To complete the drilling process I just made two more passages with a deeper Z.

When the board was finished I've seen two problem (of course..).
The first was just a trace, too narrow to be cutted by the mill. I just removed the pin header and cutted it with a razor.

The secon problem was a little too complicated..
I forgot the connection to program the board, so I made them with external wires.

The programmation of the board gave me a lot of troubles, however I have finally done, with the power of desperation!

One of the hardest part was the calibration of the sound. It reqires a lot of attempts and time. And the value depends form different factors, like voltage, resistors and microphone type.

To calculate the intensity I measured it with serial plotter and serial monitor, on Arduino libraries.