8•24 GC, 24AC, and Improved Sound

[pappadf]

[v0.7.0] — 2026-07-15

Added

• Sound on every machine — one platform audio stream with per-machine producers: the Apple Sound Chip (SE/30, IIx/IIcx, IIci, IIsi, IIfx) and a per-scanline PWM buffer scan on the Plus. Boot chimes, system beeps, and application audio (four-voice MusicWorks playback) all play reasonably well.
• Apple Macintosh Display Card 8•24 GC — model with working QuickDraw acceleration: System 6.0.8 and 7.1 bring the accelerator up through the real .GraphAccel driver and the card renders the desktop (1/8-bit pixel-exact; runtime 32-bit via Monitors).
• Apple Macintosh Display Card 24AC — NuBus colour card with QuickDraw acceleration engine; boots System 7.1 to an 8-bit colour desktop.
• Disk Copy 6.x (NDIF) images mount read-only in the image VFS (with raw export), and the VFS also reads HFS+ / HFSX volumes.

Changed

• Scheduler: two pacing modes (paced / turbo) with a single authentic CPI per machine; the Plus CPU speed is calibrated against real-hardware workloads.
• System object model: devices hang off one faithful machine.* tree (meta objects stay at root).
• VIA bus accesses synchronise to the E clock.

Fixed

• Plus mouse: physical quadrature interrupt pacing and ratio-preserving delta scaling — no more 45° staircase movement, queued-up cursor gliding, or audio breakup during mouse movement.
• web2 audio delivery: AudioWorklet start-gate re-arm and a speaker-model DC blocker remove the clicks and crackle that followed the first sound after page load.
• web2 uploads stream to OPFS on the worker, fixing Safari's "Upload failed".
• SCSI transfers larger than 128 KB (e.g. the System 7.1 installer writing the System file) no longer assert.
• External-floppy insert no longer bombs the Finder (SWIM drive select), and ADB no longer drops keyboard bytes on aborted SRQ scans.
• The 68k RESET instruction resets external peripherals, fixing warm-restart hangs with NuBus cards.

Removed

• Legacy web UI (app/web-legacy/) and its Playwright suite (tests/e2e/specs/). The web2 Svelte UI (app/web2/) is now the only frontend; make run-legacy is gone. Coverage that was unique to the legacy e2e was ported to the web2 Playwright specs (tests/e2e/web2-specs/) and the headless integration tests before removal, and CI now runs the web2 e2e suite.

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This discussion was created from the release 8•24 GC, 24AC, and Improved Sound.