neorv32/sw/ocd-firmware

NEORV32 On-Chip Debugger (OCD) - "Park Loop" Code (Firmware)

This folder contains the source code for the execution-based debugger code ROM (firmware). park_loop.S contains the "park loop" that is executed when the CPU is in debug mode. This code is used to communicate with the debug module (DM) and is responsible for:

• acknowledging halt requests
• processing and acknowledging resume requests
• processing and acknowledging "execute program buffer" requests
• executing the program buffer (provided by the DM)
• catching and acknowledging exceptions while in debug mode

The park loop code is implemented as endless loop that polls the status register of the debug memory (DM) module to check for requests from the DM and sets according flags in the status register to acknowledge these requests.

⚠️ Executing make clean_all all will NOT update the actual debugger code ROM that will be synthesized. The interface with the DM will break if there are any bugs in this code. However, if you wish to update the code ROM, copy the array content from neorv32_debug_mem.code.vhd to the code_rom_file constant in rtl/core/neorv32_debug_dm.vhd.