Pippin OS

Pippin OS refers to a version of Mac OS 7.5.2 that was stripped down and modified to be able to run on Pippin consoles launched in 1996.

Background
All consumer Pippin consoles were designed to load "Pippinized" CD-ROMs that included a streamlined version of Macintosh System 7.5.2 and would check the disc for authentication before booting. A simplified launcher called PippinFinder would directly load the application on the CD-ROM without need for the standard Finder desktop. This modified system was referred to as Pippin OS.

The Pippin OS in Japanese titles is based on a version of the Macintosh system software, then known as KanjiTalk (漢字 Talk) 7.5.2. Support for Japanese and characters used more system memory, potentially requiring a memory upgrade.

Controller input on most launch titles was supported by an early AppleJack input device driver. On March 29, 1996, right after the release of the Pippin Atmark console, Apple announced that its new Game Sprockets APIs would provide support for graphics, audio, networking and game controllers.

A developer ROM or dongle can skip the authentication process, allowing non-Pippinized Macintosh software of the era to be loaded. Developer configurations have also been known to boot System 7.5.5 through Mac OS 8.0 with varying levels of stability.

Pippin users can use CD-ROM-based shells such as PEASE or PEASE Turbo to enable network support and launch Mac applications from a standard consumer console. However, the 6MB of memory and lack of external drive support in most default configurations was a major limitation, requiring the use of Pippin memory modules or expansion docks for some applications.

Developer issues
During the development of Super Marathon, Jason Regier of Bungie found that a in the Pippin's OS would cause the console to restart instead of returning to the launch screen. Some features had to be cut to fit within the Pippin's default memory configuration. Bob Bell of found the Pippin platform to be challenging to work with during the development of The Journeyman Project: Pegasus Prime, as there was limited memory, no hardware acceleration for graphics, and no way to debug on the console.

However, Edward de Jong, who developed Action Designer: Ultraman Tiga and Anime Designer: Dragon Ball Z at Magic Mouse, called the Pippin "a superb machine for the price" and praised its openness in contrast to proprietary systems from Sega and Nintendo.

Alternate versions
Prototype consoles with early developer ROMs will only boot with a pre-release version of Mac OS 7.5.2a3. The Golden Master "GM" ROM and ROM revision 1.3 can launch versions 7.5.2, 7.5.3, 7.5.3r2, 7.5.5, 7.6.1, 8.0, 8.1 with varying degrees of stability. Consumer consoles need to bypass authentication to launch system software other than that provided on CD-ROMs authorized by Apple or Bandai.