Apple IIGS¶

Overview¶

The Apple IIGS is the most advanced member of the Apple ][ family. It introduced a 16-bit 65C816 processor, modernized graphics modes (up to 640×200 with 256 colours) and an Ensoniq ES5503 DOC wavetable sound chip while remaining strongly compatible with earlier Apple ][ software. This combination made the IIGS a popular emulator target and positioned it as a bridge between classic Apple ][ machines and the Macintosh era.

REG-Linux scrapes the apple2gs system group and, when your theme supports it, displays the dedicated artwork set for the platform.

Technical specifications¶

CPU: Western Design Center 65C816 processor at 2.8 MHz
Memory: 256 KB onboard, expandable to 1 MB and beyond with third-party cards
Display: Super High-Res mode (320×200) with up to 256 colours from a 4,096-colour palette
Sound: Ensoniq 5503 DOC with 32-channel wavetable synthesis and stereo outputs

Supported ROM extensions¶

nib, do, po, dsk, mfi, dfi, rti, edd, woz, wav, zip, 7z, plus chd, hdv, 2mg for disk dumps

Quick reference¶

ROM folder: /userdata/roms/apple2gs
Accepted formats: .nib, .do, .po, .dsk, .mfi, .dfi, .rti, .edd, .woz, .wav, .zip, .7z
Emulators: RetroArch (libretro: mame), standalone MAME, GSplus
System group: apple2gs

BIOS¶

Place the following archives into the bios folder with the exact filenames and MD5 checksums shown below. REG-Linux relies on these checksums, so do not rename or modify the files.

MD5 checksum	Share file path	Description
`4431aea380185e3f509285540d7cb418`	`bios/apple2e.zip`	Apple IIe ROM set (multiple files inside)
`e6d453d8738e6df4f73df8c8051df3e8`	`bios/apple2e.zip`	Additional Apple IIe ROM components
`72924019cf1719765e4fde35e59c1c7d`	`bios/apple2e.zip`	Additional Apple IIe ROM components
`0b150f4bfa090770a866cc5d214703f4`	`bios/apple2e.zip`	Additional Apple IIe ROM components
`2020aa1413ff77fe29353f3ee72dc295`	`bios/a2diskiing.zip`	Disk II king firmware for 5.25" drives
`95b91e4a2fe7d6f13d353ba1827d37f9`	`bios/votrax.zip`	Votrax speech ROM
`5f1be0c1cdff26f5956eef9643911886`	`bios/d2fdc.zip`	Disk II floppy disk controller ROM

ROMs¶

Store your disk images and other Apple IIGS media in /userdata/roms/apple2gs. Compressed archives (.zip, .7z) are supported, but bare images give the most predictable results.

Emulators¶

RetroArch¶

RetroArch uses the libretro: mame core for Apple IIGS emulation, providing the shared RetroArch interface (shaders, overlays, rewind, etc.). Open the Quick Menu ([HOTKEY] + south button) to tweak core options or remap inputs.

Standardized features available for all Apple IIGS libretro cores include apple2.autosave and apple2.netplay.

libretro: mame¶

ES setting name REG-Linux.conf_key	Description => ES option key_value
Settings that apply to all systems this core supports
OVERCLOCK (UNSTABLE) `global.mame_cpu_overclock`	Gentle overclocking can reduce slowdown but may destabilize certain titles. => default `default`, 30 `30`, 35 `35`, 40 `40`, 45 `45`, 50 `50`, 55 `55`, 60 `60`, 65 `65`, 70 `70`, 75 `75`, 80 `80`, 85 `85`, 90 `90`, 95 `95`, 100 `100`, 105 `105`, 110 `110`, 115 `115`, 120 `120`, 125 `125`, 130 `130`, 135 `135`, 140 `140`, 145 `145`, 150 `150`.
RENDERING RESOLUTION `global.mame_altres`	Sets the rendering resolution for clearer 3D objects. => 640x480 `640x480`, 800x600 `800x600`, 960x720 `960x720`, 1024x768 `1024x768`, 1280x720 `1280x720`, 1600x800 `1600x800`, 1920x1080 `1920x1080`, 2560x1440 `2560x1440`, 3840x2160 `3840x2160`.
SPECIAL CONTROL LAYOUTS `global.altlayout`	Alternate control layouts for fighters and other unique pad styles. => Default Only `default`, SNES Style `snes`, Genesis/Mega Drive Style `megadrive`, Modern Fightstick Style `fightstick`, Neo Geo Mini Pad `neomini`, Neo Geo CD Pad `neocd`, Twin Stick with Triggers `twinstick`, Rotated 4-Way Stick (Q*Bert) `qbert`.
HIGH SCORE PLUGIN `global.hiscoreplugin`	Toggle high-score saving. => Enabled (Default) `1`, Disabled `0`.
COIN SOUND PLUGIN `global.coindropplugin`	Play coin-drop sounds on virtual coin insertion. => Enabled `1`, Disabled (Default) `0`.
CROP ARTWORK `global.artworkcrop`	Crop artwork to maximize game screen real estate. => On (Default) `1`, Off `0`.
CUSTOM MAME CONFIG `global.customcfg`	Use a system-wide MAME config via `mame.ini`. => On `1`, Off `0`.
Settings specific to apple2
SOFTWARE LIST `apple2.softList`	Use MAME software lists to identify ROMs. => Don’t Use (Default) `none`, Apple II cleanly cracked disks `apple2_flop_clcracked`, Apple II miscellaneous disks `apple2_flop_misc`, Apple II original disks `apple2_flop_orig`.
CUSTOM GAME CONFIG `apple2.pergamecfg`	Enable per-game configuration via the MAME menu. => On `1`, Off `0`.

MAME¶

Standalone MAME is also supported. Use the in-game menu ([HOTKEY] + south button or [Tab]) to remap inputs, tweak video options and edit per-game settings. Standardized features include apple2.videomode, apple2.padtokeyboard, apple2.bezel, apple2.hud, and their related bezel/tattoo settings.

The MAME configuration table mirrors the libretro options above plus controls for video mode, BGFX API, artwork cropping and more.

GSplus¶

GSplus is an open-source emulator targeting Apple ][ and IIGS systems. REG-Linux exposes keys like apple2.videomode, apple2.padtokeyboard and apple2.decoration for GSplus.

Controls¶

Here are the default Apple IIGS controls displayed on a REG-Linux RetroPad. Use RetroArch’s Quick Menu or the emulator’s native input settings to remap buttons when needed.

Troubleshooting¶

Check that the BIOS archives in bios/ match the MD5 checksums listed above.
Confirm ROMs live under /userdata/roms/apple2gs and use one of the supported extensions.
If a title still misbehaves, try another emulator (RetroArch, MAME, GSplus) or adjust the libretro: mame configuration options.