Atari 2600¶
Overview¶
The Atari 2600 (originally the Atari VCS) debuted in September 1977 and helped define the cartridge-based home console era. Its MOS Technology 6507 CPU, TIA video/audio chip and simple yet flexible controllers made it easy to bring arcade-style games into the living room, even if ports often compromised visuals and sound. Despite the console crash of 1983, the 2600 ecosystem spurred third-party development and remains a milestone in video game history.
REG-Linux treats the system as the atari2600 group so compatible themes can show dedicated artwork.
Technical specifications¶
- CPU: MOS Technology 6507 at 1.19 MHz (cost-reduced 6502 variant)
- Memory: 128 bytes of RAM; cartridges could provide banked ROM/extra RAM
- Video: TIA chip with 160×192 resolution and artifacting-based color palette
- Sound: TIA audio with two pulse/noise channels synchronized to video timing
Supported ROM extensions¶
a26, bin, zip, 7z
Quick reference¶
- Emulator/frontend: RetroArch
- Cores: libretro: Stella, libretro: Stella2014
- ROM folder:
/userdata/roms/atari2600 - System group:
atari2600
BIOS¶
No BIOS files are required for Atari 2600 emulation in REG-Linux.
ROMs¶
Place every Atari 2600 ROM (or archive containing .a26/.bin) into /userdata/roms/atari2600. RetroArch will scan the folder and present titles from either raw dumps or .zip/.7z archives.
Emulators¶
RetroArch¶
RetroArch hosts the Stella cores for Atari 2600 emulation, providing consistent hotkeys, shaders, overlays and netplay options. Access the Quick Menu with [HOTKEY] + the south button to open advanced options and input mapping. Many of the popular settings are also surfaced via EmulationStation menus.
RetroArch configuration¶
Standardized features for the system include atari2600.videomode, atari2600.ratio, atari2600.smooth, atari2600.shaders, atari2600.pixel_perfect, atari2600.decoration and atari2600.game_translation.
| ES setting name REG-Linux.conf_key | Description => ES option key_value |
|---|---|
| Settings that apply to all cores of this emulator | |
GRAPHICS BACKEND atari2600.gfxbackend |
Choose the rendering backend (OpenGL or Vulkan). => OpenGL opengl, Vulkan vulkan. |
AUDIO LATENCY atari2600.audio_latency |
Lower values reduce input lag but may cause crackling; raise if audio glitches occur. => 256 256, 192 192, 128 128, 64 64, 32 32, 16 16, 8 8. |
THREADED VIDEO atari2600.video_threaded |
Offload video rendering to another thread; useful if you struggle to hit full speed. => On true, Off false. |
libretro: Stella¶
Stella is the official open-source Atari 2600 emulator. REG-Linux keeps the libretro port (libretro: Stella) up to date for this system.
libretro: Stella2014¶
Stella2014 is an older libretro core that prioritizes performance over accuracy. Use this core on weaker single-board computers if the main Stella core runs too slowly.
Controls¶
The default Atari 2600 layout appears on a REG-Linux Retropad:

Left and right difficulty switches map to A (Advanced) and B (Beginner). For example, use A to get a larger player ship in Space Invaders (and less forgiving collision). RetroArch’s controller settings can fine-tune the mapping if needed.
Troubleshooting¶
I have X problem with Y game¶
Many quirks are part of the original game’s design; some frames/time-critical tricks rely on the console’s unsynchronized timing. If you suspect an emulator bug or incorrect ROM behaviour, consult the libretro Stella documentation or Stella’s FAQ.
I don't remember my games being this choppy!¶
Modern LCDs often expose the Atari 2600’s variable frame timing. Using a display with variable refresh rate or enabling frame limiting may reduce judder. Running on a CRT remains the most authentic experience.