RetroArch EightyOne Core (ZX81): Documented Feature Support

What the EightyOne core is

81-libretro is a work-in-progress port of EightyOne (also known as THE Sinclair Emulator) to the libretro API, the interface used by RetroArch and other libretro frontends. It emulates the Sinclair ZX81 home computer, often nicknamed the Zeddy. The documentation labels the project as WIP, so the supported-feature picture should be read as a snapshot of the project's declared status rather than a finished-release specification.

Authorship and license

The documentation credits the EightyOne core to Michael D Wynne and lists it under the GPLv3 license. Users who redistribute builds or fork the code therefore inherit the obligations the documentation attaches to that license.

Games and Chroma 81

The documentation notes that classic ZX81 games are widely available on the Internet. It points readers toward a colorized folder for games with Chroma 81 support, and mentions original games for the Zeddy available through what the docs call Bob's Stuff. These pointers are presented as places to find software, and the documentation does not attach accuracy or compatibility guarantees to specific titles.

Documented feature support

The official documentation includes a support table for RetroArch features. The entries relevant to everyday use are summarized below; the table reflects the documentation only and has not been independently verified.

• Documented as supported:
• - Restart
• - Screenshots
• - States (save states)
• - Rewind
• - Netplay
• - Core Options
• - Controls

• Documented as not supported:
• - Saves (battery-backed game saves)
• - Memory Monitoring (achievements)
• - RetroArch Cheats
• - Native Cheats
• - Remapping
• - Softpatching
• - Disk Control

What the support table means in practice

The supported/unsupported split shapes a few practical decisions. Controllers work and remapping does not, so expect to use the default control layout rather than rebinding per game. Save states and rewind are both listed as supported, which gives players a way to step back through tricky sequences. Netplay is listed as supported, opening the door to connected sessions. Core Options are available, so behavior exposed as core settings is adjustable from the frontend.

On the unsupported side, achievements monitoring is listed as unavailable, so RetroAchievements-style progress tracking is not documented as a feature of this core. RetroArch cheats and native cheats are both listed as unsupported. Softpatching and disk control are likewise not documented as available, so per-game patches and multi-disk swapping are not part of the documented feature set.

Who this reference is for

This summary is aimed at RetroArch users and retro-computing enthusiasts who want to know what the EightyOne core documents before setting up ZX81 emulation. It does not provide a step-by-step install procedure, because the source documentation summarized here focuses on background, authorship, licensing and the feature support table rather than installation steps.