On the wiki for this product (SKU: 110060136) there are eagle files for the proto board but not for the USB-Serial daughter board (ATMEGA16U2 breakout). It would be nice to have the eagle files for this, also.
The USB-Serial daughter board has 8 pins on the right hand side all apparently connected to ground. It would be interesting to know if they are actually tied to the ground plane of the board or are in fact additional I/O pins of the MCU set low by the firmware. Does anybody know?
Seems an aweful waste of I/O to not break out some of the unused ones to these unused connection pins…
I’ve ordered a couple of these kits and will investigate after they arrive, but thought somebody might just have the answer already.