Some subsystems (e.g, EPS, GNSS, MPI) are expensive devices, and/or can only be used in certain at-school environments. The facilitate development and testing, we can emulate these subsystems using software running on a computer and/or Arduino.

By using a USB-to-UART converter plugged into the STM32 dev kit on the UART port that the subsystem is expected, and then by running a Python script (which mimics the messaging of the subsystem), we can test the firmware as though it's connected to the actual subsystem.

Python Emulation Scripts

Emulation scripts exist for the following subsystems, in the following modes:

GNSS: Dump GNSS data to the STM32 once every second.
MPI: Respond to MPI commands from the STM32.
MPI: Dump MPI science data to the STM32 very rapidly.
- TODO: implement/check on this one ^

Python Serial Terminal

The Python serial terminal is useful for receiving only.

For example, if you are testing a system which sends a command to the GNSS, for example, you can use this to view the commands sent from the STM32 to the GNSS, assuming the USB-to-UART converter is connected to the GNSS UART lines on the STM32.

# Install the Python serial terminal. Only need to run one time.
python3 -m pip install pyserial
 
# Run the terminal, in basic mode, with 115200 baud rate.
python3 -m serial.tools.miniterm - 115200
 
# Run the terminal, showing incoming data in hex.
python3 -m serial.tools.miniterm - 115200 --encoding hexlify