Atari TOS

The Atari TOS debut with the Atari 520ST in 1985. TOS combined Digital Research's GEM GUI running on top of the DOS-like GEMDOS. Features included a flat memory model, MS-DOS-compatible disk format, support for MIDI, and a variant of SCSI called ACSI (in later versions). One of the most interesting aspects of Atari's TOS was that it came on ROM chips, thus before local hard drives were available in home computers it was an almost instant-running OS.

Related:
Operating Systems

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