You can 3D print a new back cover that fits the Raspberry Pi socket, as follows:
After plug in the Raspberry Pi board , power on the BiBoard via USB data cable or Battery.
Software Setup
Open the serial monitor, and send serial command XS to enable the Serail 2 working mode.
You can also modify the source code (OpenCat.h) and upload the sketch for BiBoard to enable the Serail 2 working mode:
Serial port name on Pi
Generally, the serial port name on Raspberry Pi 3 and 4 is "/dev/ttyS0," and the one on Raspberry Pi 5 is "/dev/ttyAMA0." If the Pi can't open the serial port after it is connected to the mainboard, you can uncomment the line of code as follows to check all the serial ports on the Raspberry Pi in the terminal when the Python script(ardSerial.py) is running.
