This customized board (https://www.dexterindustries.com/GoPiGo/learning/hardware-port-description/) provides the general features that are expected from a controller:
- Real-time communication with sensors and actuators.
- Interface input/output (I/O) through a serial peripheral interface (SPI) that feeds the data from the sensors to the Raspberry Pi and may also receive commands for the actuators (also from the Raspberry Pi, after running the logic in its CPU for every step of the control loop).
- One single program loaded on board, known as the firmware. Since the goal of this software is to implement a communication protocol while the computer implements the logic, it doesn't need to be changed unless you decide to upgrade ...