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These two models can be upgraded via the M0244 upgrade kit (which replaces the IWM disk controller with the SWIM) and gain full use of the SuperDrive.
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The next two models to be released ( Macintosh II & Macintosh SE (1987)) also shipped with that controller a SuperDrive connected to them will behave as an 800 KB drive. The SuperDrive cannot be used with the original four Mac models ( Macintosh 128K through Macintosh Plus), as their disk controller (the IWM) doesn't support high density. The controller card as well as the external Superdrive were discontinued in June 1994. While the external drive worked on both Apple's product lines, it was mainly intended for use on the Apple II series, for which Apple introduced in 1991 a slot-based interface called the Apple II 3.5 Disk Controller Card for Apple IIe and II GS computers so they too could use 1.40 MB storage and read/write MS-DOS. Introduced in 1988 under the Trademark name FDHD (Floppy Disk High Density), the subsequently renamed SuperDrive was known primarily as an internally mounted floppy drive that was part of the Macintosh computer however, an external version of the drive was manufactured that came in a Snow White-styled plastic case.Īpple II 3.5 Disk Controller Card & Apple SuperDrive This was made possible as the SuperDrive now utilitized the same MFM (Modified Frequency Modulation) encoding scheme used by the IBM PC, yet still retained backward compatibility with Apple's variable-speed zoned CAV scheme and group coded recording encoding format, so it could continue to read Macintosh MFS, HFS and Apple II ProDOS formats on 400/800 KB disks. This drive was also capable of reading and writing MS-DOS formatted disks and FAT12 file formats, using PC Exchange or other software, unlike the 400 KB and 800 KB drives. This replaced the older 800 KB floppy drive that had been standard in the Macintosh up to then, but remained compatible in that it could continue to read and write both 800 KB (double-sided) and 400 KB (single-sided) floppy disks, as well as the newer high-density floppies. The term was first used by Apple Computer in 1988 to refer to their 1.44 MB 3.5 inch floppy drive.
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Internal SuperDrive floppy drive on a Macintosh LC II
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