Intro

So this is about Understanding Shinobi, the Sega System 16 arcade game. It's mostly an exploration or exercise, nowadays you can play the game as it was in the arcades in multiple ways (emulation, versions for Nintendo Switch, Wii etc). But by understanding it we may port it to older platforms with some degree of fidelity. 

The main things we are trying to understand are:

  • How to extract the original artwork from the ROM dump
  • Having the exact code for movement, enemy behavior etc., so it can be ported with high fidelity and without guesswork
The first one does not seem too hard, the second requires analyzing the original M68k code to try to get to the specific subroutines. This can be a lot of work or it can be made easier if good tools are available. This is still to be determined. 

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