!!! Atari Dos 3 DOS 3 shipped with 1050 disk drives from 1983-1985. It was created in part to take advantage of the 1050's Dual-Density capability, by employing a single- sided, enhanced-density 128K 5.25" floppy disk drive format. Atari called this format "dual-density," but the Atari community quickly came to refer to this format as "enhanced-density" to better differentiate it from widely available 3rd-party truly double density disk drives and supporting versions of DOS. DOS 3 uses a disk format incompatible with DOS 2.0S. It included a utility to convert files from DOS 2.0S to DOS 3, but not back again. It used disk space less efficiently than DOS 2.0S. For these reasons and others, DOS 3 was not widely accepted by the Atari community, and like DOS 1 is not generally used except for curiosity's sake. The DOS 3 disk is labeled: Master Diskette 3 (DX5052). * [Wikipedia: Atari DOS 3|http://en.wikipedia.org/wiki/Atari_DOS#DOS_3.0] !Manuals * Atari DOS 3 (english) [PDF, 14.4MB|Atari DOS 3/AtariDOS3Handbook.pdf] [DJVU, 1.7MB|Atari DOS 3/AtariDOS3Handbook.djvu] * Atari DOS 3 (german) [PDF, 3.2MB|Atari DOS 3/dos 3 handbuch.pdf]