2.2 KiB
crater
crater is an emulator for the Sega Game Gear, written in C.
Why?
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.
Installing
Only OS X and Linux are tested. You’ll need a decent 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.
Usage
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 should end in
.gg or .bin.
Add --fullscreen (-f) to enable fullscreen mode, or --scale <n>
(-s <n>) to scale the game screen by an integer factor.
./crater -h gives (fairly basic) command-line usage, and ./crater -v gives
the current version.
Advanced options
crater supports several advanced features. 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.
--assemble <input> [<output>] (-a) converts z80 assembly 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 .s for -d. By default, this will never overwrite the original filename;
pass --overwrite (-r) to let crater do so.