/olcNESfpc

Pascal port of olc6502 Tutorial 2

Primary LanguagePascal

olcNES - Object Pascal version

NES Emulator, and Tutorial Video Code - ported to Object Pascal. IMAGE ALT TEXT HERE

This is a rather quick port of the olc 6502 emulator from C++ to Object Pascal, or more specifically, FreePascal in Lazarus form. While I made an effort to cater for what I remember from Delphi, minor work will have to be done to get it to work.

I tried to keep everything as similar to the original C++ code, but had to make a few changes here and there to get things to work, such as:

  • adding underscores to the operation functions, due to e.g., AND being a reserved word.
  • I could not for the life of me figure out how to compare the addresses of method functions, so added a gross enum to state what method was being used
  • having never used Generics before, I didn't know how to duplicate the C++ std::map procedure of 1. find item in map 2. enumerate from that item towards the end of the map. So instead I store a map of memory_line:source_line, and store the disassembled source into a stringlist, which I reference with source_line, and can move freely before and after it.

As with the source of this conversation, it's not optimised in the slightest, more a straight forward example of how everything 6502 works.

License (OLC-3)

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