21 lines
1.1 KiB
Markdown
21 lines
1.1 KiB
Markdown
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# NEORV32 On-Chip Debugger (OCD) - "Park Loop" Code (Firmware)
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This folder contains the source code for the *execution-based* debugger code ROM (firmware).
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`park_loop.S` contains the "park loop" that is executed when the CPU is in debug mode. This code
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is used to communicate with the *debug module (DM)* and is responsible for:
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* acknowledging halt requests
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* processing and acknowledging resume requests
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* processing and acknowledging "execute program buffer" requests
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* executing the program buffer (provided by the DM)
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* catching and acknowledging exceptions while in debug mode
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The park loop code is implemented as endless loop that polls the status register of
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the _debug memory (DM)_ module to check for requests from the DM and sets according flags in the
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status register to acknowledge these requests.
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:warning: Executing `make clean_all all` will **NOT** update the actual debugger code ROM that
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will be synthesized. The interface with the DM will break if there are any bugs in this code.
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However, if you wish to update the code ROM, copy the array content from `neorv32_debug_mem.code.vhd`
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to the `code_rom_file` constant in `rtl/core/neorv32_debug_dm.vhd`.
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