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Master the fundamental concepts of real mode programming through this focused micro-challenge.
Different segment:offset pairs can alias the same physical byte. 0000:7C00, 07C0:0000, and 7000:0C00 all map to 0x7C00. For example, a far jump to 0x0000:0x7C00 after loading a sector uses a different segment pair than the BIOS default 0000:7C00 but lands on identical physical memory.
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Watch wraparound: 0xFFFF:0x0010 becomes 0x00000 without A20.
Boot loaders often normalize CS to 0x0000 with IP=0x7C00 after a manual reload even though the BIOS entered at 07C0:0000. Understanding aliasing prevents off-by-16 bugs when mixing assembly modules assembled with different ORG assumptions. Label addresses in listings are offsets from ORG; always add the load address when reasoning about physical placement.
You will convert between segment:offset pairs and physical addresses in both directions. This exercise requires demonstrating overlapping segments and near/far pointer differences with concrete numeric examples.
Implement a segmented memory addressing simulator in C.
Requirements:
Test:
Three hints are available for this task, revealed one at a time inside the code workspace so you can struggle productively before seeing them.
All starter code and reference implementations are available for your local setup.
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