Ben Kurtovic c46f1045ce | pirms 9 gadiem | |
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roms | pirms 10 gadiem | |
src | pirms 9 gadiem | |
tests | pirms 9 gadiem | |
.gitignore | pirms 10 gadiem | |
LICENSE | pirms 9 gadiem | |
README.md | pirms 9 gadiem | |
crater.c | pirms 9 gadiem | |
makefile | pirms 9 gadiem |
crater is an emulator for the Sega Game Gear, with an included Z80 assembler/disassembler, written in C.
While the internet is full of emulators for retro game systems, writing one is nevertheless a fun learning project.
crater is named after 31 Crateris, a star that was – for a short time in 1974 – misidentified as a moon of Mercury. Mercury was Sega’s codename for the Game Gear during development.
Only OS X and Linux are tested. You’ll need a modern compiler that supports C11
(clang preferred) and SDL 2. Using Homebrew, you can brew install sdl2
; using
apt, you can apt-get install libsdl2-dev
.
Run make
to create ./crater
. To build the development version with debug
symbols (they can exist simultaneously), run make DEBUG=1
, which creates
./crater-dev
. This also enables the printing of debugging info to stdout.
Running ./crater
without arguments will display a list of ROM images located
in the roms/
directory, and then ask the user to pick one, or enter their own
ROM path. You can provide a path directly with ./crater path/to/rom
.
Add or symlink ROMs to roms/
at your leisure. Note that they must end in
.gg
or .bin
to be auto-detected.
Add --fullscreen
(-f
) to enable fullscreen mode, or --scale <n>
(-s <n>
) to scale the game screen by an integer factor.
Add --debug
(-g
) to display detailed information about emulation state
while running, including register values and memory contents. You can also
pause emulation to set breakpoints and change state.
./crater -h
gives (fairly basic) command-line usage, and ./crater -v
gives
the current version.
crater has built-in support for converting Z80 assembly into ROM images, as well as attempting the reverse process (i.e., disassembling).
--assemble <input> [<output>]
(-a
) converts source code into a .gg
binary
that can be run by crater. --disassemble <input> [<output>]
(-d
) executes
the opposite operation. If no output file is given, crater will use the name of
the input file, with the extension replaced with .gg
for -a
and .asm
for
-d
. By default, this will never overwrite the original filename; pass
--overwrite
(-r
) to let crater do so.