Macintosh External Disk Drive
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Developer | Apple Computer |
---|---|
Type | Disk drive |
Release date | May 4, 1984 |
Introductory price | US$495 |
The Macintosh External Disk Drive is the original model in a series of external 3+1⁄2-inch
400K
The original Macintosh External Disk Drive (M0130) was introduced with the Macintosh on January 24, 1984. However, it did not actually ship until May 4, 1984, sixty days after Apple had promised it to dealers. Bill Fernandez was the project manager who oversaw the design and production of the drive.[1] The drive case was designed to match the Macintosh and included the same 400-kilobyte drive (a Sony-made 3+1⁄2-inch single-sided mechanism) installed inside the Macintosh. Although very similar to the 400-kilobyte drive which newly replaced Apple's ill-fated Twiggy drive in the Lisa, there were subtle differences relating mainly to the eject mechanism. However, confusingly all of these drives were labelled identically. The Macintosh could only support one external drive, limiting the number of floppy disks mounted at once to two, but both Apple and third party manufacturers developed external hard drives that connected to the Mac's floppy disk port, which had pass-through ports to accommodate daisy-chaining the external disk drive. Apple's Hard Disk 20 could accommodate an additional daisy-chained hard drive as well as an external floppy disk.
3.5-inch single-sided floppies had been used on several microcomputers and synthesizers in the early 1980s, including the
The external 400-kilobyte Macintosh drive will work on any Macintosh that does not have a high density SuperDrive controller (due to electrical changes with the interface), but the disks in practice only support the MFS file system. Although a 400-kilobyte disk may be formatted with HFS, it cannot be booted from, nor is it readable in a Mac 128 or 512.
Copy protection schemes were not as elaborate or widespread on Macintosh software as they were on Apple II software for several reasons. First, the Mac drives did not afford the same degree of low-level control. Also Apple did not publish source listings for the Mac OS ROMs as they did with the Apple II. Finally, the Mac OS routines were considerably more complex and disk access had to be synchronized with the mouse and keyboard.
800K
By early 1985, it was clear that the Macintosh needed additional storage space, in particular a hard drive. Apple announced their first hard drive for the Mac in March 1985. However, the MFS file system did not support subdirectories, making it unsuitable for a hard disk. Apple quickly began adopting for the Mac the hierarchical based SOS filing system introduced with the Apple III and long since implemented in ProDOS for the Apple II series and the Lisa. This change in the Mac's filing system delayed the introduction of the double sided Sony drives which Apple intended to offer as soon as the technology was available, a concession they made when adopting the Sony drives over their own problematic double-capacity Twiggy drives.[2][3] However, based on the success of the 3.5-inch floppy drive for the Mac, there was no such obstacle in immediately implementing an 800-kilobyte drive for the Apple II, so it was introduced in September 1985, four months before the version for the Mac. While Apple simultaneously introduced their new hard drive after a 6-month delay, they chose not to implement the new floppy drive for the Macintosh at that time.
Apple UniDisk 3.5
In September 1985, Apple released its first 3+1⁄2-inch drive (A2M2053) for the Apple II series utilizing Sony's new 800-kilobyte double-sided drive mechanism, which would not be released for the Macintosh until four months later. The Apple UniDisk 3.5 drive contained additional circuitry making it an "intelligent" or "smart" drive; this made it incompatible with the Macintosh, despite having the identical mechanism that was to be later used in the Macintosh drive. However, if the internal circuit board (which consisted of its own
Macintosh 800K External Drive
In January 1986, Apple introduced the
Apple 3.5 Drive
Beginning in September 1986, Apple adopted a unified cross-platform product strategy essentially eliminating platform-specific peripherals where possible. The Apple 3.5 Drive (A9M0106) is an 800K external drive released in conjunction with the Apple IIGS computer and replaced the beige-colored Macintosh 800K External Drive. It works on both the Apple IIGS as well as the Macintosh. It came in a case similar to the UniDisk, but in Platinum gray. Like the UniDisk 3.5, the Apple 3.5 Drive includes Apple II-specific features such as a manual disk eject button and a daisy-chain connector which allows two drives to be connected to an Apple II computer. The Macintosh however could still only accommodate one external drive, and ignores use of the eject button. Unlike the Macintosh 800K External Drive, the Apple 3.5 Drive can be used natively with the 64-kilobyte ROM stock Macintosh 128K & 512K computers without the HD20 INIT, albeit only with 400K MFS formatted disks. Designed as a universal external drive replacement, the Apple 3.5 Drive was eventually made compatible with the remaining Apple II models in production upon the introduction of the Apple IIc Plus and the Apple II 3.5 Disk Controller Card for the Apple IIe.
1.44MB
Following the success of the Macintosh implementation of the 3+1⁄2-inch format, the format was also adopted widely by the personal computer industry. However most of the industry adopted a different
Apple FDHD Drive
Later renamed the Apple SuperDrive (G7287), the Apple FDHD Drive (Floppy Disk High Density) was introduced in 1989 as Apple's first external 1.44 MB high-density double-sided 3+1⁄2-inch floppy drive. It supported all of Apple's 3.5" floppy disk formats as well as all standard PC formats (e.g. MS-DOS, Windows), allowing the Macintosh to read and write all industry-standard floppy disk formats. The external drive was offered only briefly with support for the Apple II, coming late in that product's life. To take advantage of the drive's extended storage and new capabilities, it required the new SWIM (Sander–Wozniak Integrated Machine) floppy disk controller chip to be present on the Macintosh and Apple II, the latter requiring the Apple II 3.5 Disk Controller Card which integrated the chip. If the drive was connected to an older Macintosh, Apple IIGS or Apple IIc Plus with the older IWM (Integrated Woz Machine) chip, the drive would act as a standard 800K drive, without any additional capabilities. The interface card was necessary for the Apple IIGS to make use of its greater storage capacity and ability to handle PC formats. The Apple IIe could not utilize the drive in any form, unless it had the specialized interface card installed, much like the UniDisk 3.5 which the SuperDrive replaced. The last Mac it could be used with was the Classic II and was discontinued shortly thereafter. The drive was fitted in every desktop Mac from its introduction and was eliminated with the introduction of the iMac in 1998. PowerPC Macs dropped the original auto-inject Sony drives and went to a manual inject mechanism.
Macintosh HDI-20 External 1.4MB Floppy Disk Drive
Manufactured exclusively for use with the Macintosh PowerBook line, the Macintosh HDI-20 External 1.44MB Floppy Disk Drive (M8061) contained a low-powered, slimmer version of the SuperDrive and used a small square HDI-20[5] proprietary connector, rather than the larger standard DE-19 desktop connector, and was powered directly by the laptop. It had a matching dark gray case and an access cover which flipped down to form a stand. The external drive was sold optionally for those PowerBooks which had no built-in drive, however, the identical drive mechanism was included internally in some PowerBook models, which otherwise had no provision to accommodate an external drive.
Macintosh PowerBook 2400c Floppy Disk Drive
Compatible only with the PowerBook 2400c, the Macintosh PowerBook 2400c Floppy Disk Drive (M4327) used a unique Molex connector[6] rather than the previous HDI-20 connector. Possibly because of the 2400c's IBM design heritage, both the drive and the computer use the same connectors as IBM ThinkPad external floppy drives from the same period; however, IBM drives are not electrically compatible.[7] The drive was discontinued in 1998 and would be the last external floppy drive manufactured by Apple.
See also
- List of Apple drives
- Macintosh File System
- History of the floppy disk
- Timeline of Apple Inc. products
References
- ^ "Bill Fernandez Portfolio". Archived from the original on May 24, 2009. Retrieved July 16, 2009.
- ^ "Rumor Mill at the Expo". MacTech Mousehole (Letters). Vol. 1, no. 5. April 1985. Archived from the original on March 15, 2009. Retrieved July 18, 2009.
- ^ Herzfeld, Andy (August 1983). "Macintosh Stories: Quick, Hide In This Closet!". Folklore.org. Archived from the original on November 17, 2008. Retrieved July 18, 2009.
- ISBN 0-940235-00-5.
- ^ "HDI-20". Archived from the original on May 11, 2012. Retrieved June 1, 2012.
- ^ "PowerBook 2400c Developer Note" (PDF). Archived from the original on July 21, 2004. Retrieved September 30, 2016.
{{cite web}}
: CS1 maint: bot: original URL status unknown (link) - ^ "2400c questions: Sound + PCMCIA Ethernet". 68kMLA Forums. Archived from the original on October 2, 2016. Retrieved September 30, 2016.
External links
- Macintosh: Support for External Floppy Drives (at Apple support site)
- vintagemacworld.com Archived November 30, 1998, at Wikiwix Apple External Drives