Sega - MS/GG (Gearsystem)¶
Background¶
Gearsystem is an open source, multi-platform, Sega Master System / Game Gear / SG-1000 emulator written in C++.
- Highly accurate Z80 core, including undocumented opcodes and behaviour like R and MEMPTR registers.
- Multi-Mapper support: SEGA, Codemasters, SG-1000 and ROM only cartridges.
- Automatic region detection: NTSC-JAP, NTSC-USA, PAL-EUR.
- Internal database for rom detection
- Highly accurate VDP emulation including timing and SMS2 only 224 mode support.
- Audio emulation using SDL Audio and Sms_Snd_Emu library.
- Battery powered RAM save support.
- Save states.
- Game Genie and Pro Action Replay cheat support.
- Runs on Windows, Linux, Mac OS X, Raspberry Pi, iOS and as a libretro core (RetroArch).
The Gearsystem core has been authored by
- Ignacio Sanchez
The Gearsystem core is licensed under
A summary of the licenses behind RetroArch and its cores have found here.
BIOS¶
Not required.
Extensions¶
Content that can be loaded by the Gearsystem core have the following file extensions:
- .sms
- .gg
- .sg
- .bin
- .rom
RetroArch database(s) that are associated with the Gearsystem core:
Features¶
Frontend-level settings or features that the Gearsystem core respects.
| Feature | Supported |
|---|---|
| Restart | ✔ |
| Screenshots | ✔ |
| Saves | ✔ |
| States | ✔ |
| Rewind | ✔ |
| Netplay | ✕ |
| Core Options | ✔ |
| RetroAchievements | ✔ |
| RetroArch Cheats - Game Genie | ✔ |
| RetroArch Cheats - Pro Acion Replay | ✔ |
| Native Cheats | ✕ |
| Controls | ✔ |
| Remapping | ✔ |
| Multi-Mouse | ✕ |
| Rumble | ✕ |
| Sensors | ✕ |
| Camera | ✕ |
| Location | ✕ |
| Subsystem | ✕ |
| Softpatching | ✔ |
| Disk Control | ✕ |
| Username | ✕ |
| Language | ✕ |
| Crop Overscan | ✕ |
| LEDs | ✕ |
Directories¶
The Gearsystem core's library name is 'Gearsystem'
The Gearsystem core saves/loads to/from these directories.
Frontend's Save directory
| File | Description |
|---|---|
| *.srm | Cartridge battery save |
Frontend's State directory
| File | Description |
|---|---|
| *.state# | State |
Geometry and timing¶
- The Gearsystem core's core provided FPS is 60 for NTSC games and 50 for PAL games
- The Gearsystem core's core provided sample rate is 44100 Hz
- The Gearsystem core's base width is 256 for Master System / SG-1000 games and 160 for Game Gear games
- The Gearsystem core's base height is 192 for Master System / SG-1000 games and 144 for Game Gear games
- The Gearsystem core's max width is 256 for Master System games and 160 for Game Gear games
- The Gearsystem core's max height is 224 for Master System games and 144 for Game Gear games
- The Gearsystem core's core provided aspect ratio is 4:3 for Master System / SG-1000 games and 10:9 for Game Gear games
Joypad¶
| User 1 input descriptors | RetroPad Inputs |
|---|---|
| 1 |  |
| Start |  |
| Up |  |
| Down |  |
| Left |  |
| Right |  |
| 2 |  |
Compatibility¶
External Links¶
- Official Gearsystem Repository
- Libretro Gearsystem Core info file
- Report Libretro Gearsystem Core Issues Here
See also¶
Sega - Game Gear¶
Sega - Master System - Mark III¶
- Sega - Master System (Emux SMS)
- Sega - MS/GG/MD/CD (Genesis Plus GX)
- Sega - MS/MD/CD/32X (PicoDrive)