39 lines
1.7 KiB
Markdown
39 lines
1.7 KiB
Markdown
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# Assembler configuration files
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These files are used by the [assembler][assembler] to use custom MMU mappings in the resulting [bytecode file][bin_file].
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## File format
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This file is a text file for ease of creation on the calculator. It is parsed by splitting it around the UNIX newline character, and numbers are written in hex without prefix.
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### First line
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The first line represents the entry point, which is the address of the first instruction to be executed by the [processor][proc].
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### Second line
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The second line contains the offset at which the code is located in RAM, as seen by the [assembler][assembler].
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### Subsequent lines
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All subsequent lines are individual segment information, with the first line being the type, **in decimal**.
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### Common data
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Second line of a block is the access code, which is a combination (binary OR) of these access codes:
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`4`: read
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`2`: write
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`3`: execute
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Third line is the offset at which the segment will reside in RAM.
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Fourth line is the length of the block in RAM.
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## Block types
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Block type 0 represents the ROM, which is just the contents of the [bytecode file][bin_file], excluding the header.
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Block type 1 represents RAM, which will be zeroed-out before being mapped.
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Block type 2 represents the stack, which can be mapped in RAM.
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Block type 3 represents a file to be linked recursively. Beware, as infinite loops will **not** be detected.
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Block type 4 represents a file to be mapped directly. Beware, as a `RW` file will actually be written to disk on memory write.
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Block type 5 represents the VRAM which will always be mapped as `RW`.
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Block types 3 and 4 have a special field which is the filename, in raw ASCII.
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[assembler]: ./assembler.md
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[bin_file]: ./bin_file.md
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[proc]: ./proc.md
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