Description

This pull request adds support for using USB Serial JTAG as the serial interface in Wokwi simulations, alongside comprehensive unit tests and integration into the pytest-embedded workflow. It introduces a new CLI flag, updates diagram processing to support the new interface, and ensures that the original diagram files remain unmodified. Additionally, the changes are well-documented in the README and thoroughly tested.

USB Serial JTAG Support and Diagram Handling:

• Added a new --wokwi-usb-serial-jtag command-line option, allowing users to select USB Serial JTAG instead of UART for serial communication in Wokwi simulations. This is reflected in both the plugin options and dut_factory interfaces. [1] [2] [3] [4] [5]
• Implemented logic in Wokwi to override the serial interface in diagram files: sets serialInterface to USB_SERIAL_JTAG on the board part and removes $serialMonitor connections. The modified diagram is written to a temporary file, preserving the original. [1] [2] [3] [4]
• Updated the README with documentation and usage instructions for the new USB Serial JTAG feature.

Testing and Validation:

• Added a suite of unit tests for the serial interface override logic, verifying correct modification of diagrams, preservation of non-serial connections, non-mutation of the original file, and proper handling of missing or existing attributes. [1] [2]

Integration and Parametrization:

• Extended all relevant pytest-embedded plugin and fixture code to accept and propagate the new wokwi_usb_serial_jtag parameter, supporting both CLI and parametrized test usage. [1] [2] [3]

These changes collectively make it easy to test firmware using USB Serial JTAG in Wokwi, with robust handling and clear user documentation.

Testing

Locally and CI