GSSquared

What’s new

Highlights from recent GSSquared Apple II emulator releases. For deep technical notes, see the project documentation and GitHub releases.

Version 0.11 ·

GSSquared 0.11 — talk to the real machine

This release is about connecting the virtual Apple II to the host: real serial ports, print-to-clipboard, Host FST on Windows — plus CRT shaders on Windows and Linux, Second Sight Apple II text, CD-ROM volumes, and a large round of IIgs timing and MMU accuracy.

  • Host serial ports Attach a real host UART to IIgs SCC or Super Serial from the Control Panel or config editor — macOS /dev/cu.*, Windows COMn, Linux USB serial. Guest baud, data, parity, and stop bits pass through; unplugged dongles stay attached and retry.
  • Print to clipboard Serial and parallel ports can attach a Clipboard device. Guest output is copied to the host clipboard after a short idle or Ctrl-Reset, with a toast for the byte count.
  • CRT shader on Windows and Linux The GPU CRT look that was already on macOS now ships on Windows and Linux. Toggle with Display → CRT Shader or F7 — no extra compiler SDKs required.
  • Host FST on Windows Share a host folder with GS/OS as :Host on 64-bit Windows. ProDOS type/auxtype, Finder info, and resource forks live in NTFS Alternate Data Streams.
  • Second Sight Apple II text With a Second Sight card, Display → Second Sight Text renders 40- and 80-column Apple II text through the card’s VGA path.
  • CD-ROM and APM volumes Mount .iso CD dumps (always write-protected). Apple Partition Map images expose each ProDOS and HFS partition as its own SmartPort unit — the usual path for 1990s IIgs CD-ROMs.
  • IIgs accuracy and paste Timing and MMU fixes (including textfunk), ludicrous-speed video that still scans, GS/OS mouse tracking on 640-pixel SHR, and Edit → Paste Text on the IIgs ADB path.

Version 0.10 ·

GSSquared 0.10 — plug it in

This release expands what you can plug into a virtual Apple II: Ethernet, serial, Host FST file sharing, and Mouse III — plus a full Apple IIgs ROM 03 machine, everyday quality-of-life tools, and a pile of accuracy fixes for sound, mouse, memory, and floppy behavior.

  • Apple IIgs ROM 03 A first-class ROM 03 machine alongside ROM 01, with correct 256K ROM mapping and GS/OS boot fixes so ROM 03 systems are usable out of the box.
  • Uthernet II Ethernet for the Apple II and IIgs via slirp — works on macOS, Windows, and Linux with no host TAP or bridge setup for typical use.
  • Super Serial Card SSC emulation for serial I/O, with in-app connection management shared with other serial and parallel devices.
  • IIgs Host FST Share files with the host from GS/OS. Mount the built-in drivers volume from the menu to install Host FST and the host driver.
  • Apple Mouse III New Mouse III card support — Mouse II setups redirect to the III implementation.
  • Screenshots, HUD, and stereo Save a screenshot straight to a file, hide the stats overlay and drive icons when you want a clean screen, and Ensoniq DOC stereo output with stereo drive-seek effects.

Version 0.9 ·

GSSquared 0.9 — make it yours

This release is about fitting the emulator to how you work: custom hardware profiles, better GS/OS mouse feel, optional CRT post-processing, and more polish across Mac, Windows, and Linux.

  • Custom system profiles Define a machine in a profile — platform, cards, storage, video — then launch it like a first-class system. Edit profiles in-app when you want to tweak without leaving the emulator.
  • Smoother GS/OS mouse tracking More reliable pointer sync, including when letterboxing or CRT bezels are in play.
  • CRT post-processing Optional GPU-based CRT look for a more authentic display (with a clean fallback when needed).
  • SecondSight VGA card (initial support) Early emulation for SecondSight on supported setups.
  • High-DPI and desktop polish Better behavior on modern displays across host platforms.
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