*3.2. Electronic Boards*

The "core" of the OpenSWAP hardware is constituted by a single-board multilayer PCB (printed circuit board), displayed in Figure 4, designed and developed to host embedded subsystems and boards (Arduino®, Raspberry™, Xbee, etc). It provides all connections and power supplies to electronic boards and devices, as well as signal conditioning circuits and I/O ports. Several jumper pins are included to quickly modify settings and parameters according to special setups and/or payloads. This is the only electronic component not available in the consumer market and distributed by Proambiente (https://www.openswap.it/).

**Figure 4.** *Cont*.

**Figure 4.** Block-diagram (**top**) and photo (**bottom**) of the OpenSWAP mainboard.
