Getting started

This repository does not ship the cartridge. It ships the commented listing and the tools that generate it, check it and draw its screens.

What you need

• make, python3 and pasmo to reassemble
• z80dasm only if you want to trace again from scratch
• openMSX for the VRAM comparison (optional)
• the cartridge, boxing.rom, exactly 32,768 bytes, with this sha256:

43b23739d63b636922f0a98c33322bfdeafbefeccc01dd74fb0a45107581d0e6

The four steps

make comprueba   # that the cartridge is what it claims to be
make listado     # builds src/boxing.asm from the trace and the notes
make verify      # reassembles it and compares the sha256 with the original
make all         # all of the above, plus the checks and the 42 tests

make verify is what decides whether the disassembly is trustworthy: if the listing does not give back the ROM byte for byte, nothing it says is worth anything.

What make sanity checks

Reassembling does not catch everything. A block of data read as code comes out the same, because the bytes do not change; only what we say about them does. Hence four more checks:

check	what it watches
check_trace.py	that the trace never wanders into declared data
check_datos_como_codigo.py	that none of the 416 data areas comes out as code
check_entradas.py	that no entry point falls inside a data area
presupuesto.py	that not one byte of the cartridge is left unassigned

The pictures

make imagenes    # the fourteen plates in docs/img, drawn from the ROM
make vram        # openMSX dumps its VRAM and it is compared byte for byte

Not one picture on this site is a capture. They are built by running in Python the same steps the cartridge takes, and the comparison against the emulator's VRAM comes out with zero differences on all eight screens.