Macintosh External Disk Drive
Encyclopedia
The Macintosh External Disk Drive was the original of a series of external 3.5" floppy disk
drives manufactured and sold by Apple Computer
exclusively for the Macintosh
series of computers introduced in January, 1984. Later, Apple would unify their external drives to work cross-platform between the Macintosh and Apple II
product lines, dropping the name "Macintosh" from the drives. Though Apple had been producing external floppy disk drives
prior to 1984, they were exclusively developed for the Apple II, III
and Lisa
computers using the industry standard 5.25" flexible disk format. The Macintosh external drives were the first to widely introduce Sony
's new 3.5" rigid disk standard commercially and throughout their product line. Apple produced only one external 3.5" drive exclusively for use with the Apple II series called the Apple UniDisk 3.5.
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. The drive case was designed to match the Macintosh and included the same 400K drive installed inside the Macintosh. Although very similar to the 400K drive which newly replaced Apple's ill-fated Twiggy drive
in the Lisa, there were subtle differences relating mainly to the eject mechanism. However, all of these drives were labeled confusingly identically. The Macintosh could only support one external drive, limiting the number of floppy disks mounted at once to two. However, 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. The standard formatted capacity of the drive was 360K, however, Apple employed its GCR
formatting technique which spun the disk at a different rate on the outer edges to increase the total disk storage. Despite the greater storage capacity, the drive could not be used on the Apple II. Nor could the Lisa accommodate it as an external drive, despite being originally offered with two 871K drives. These drives only support the original Macintosh File System
(MFS), though they can be used on any Macintosh which does not also support a SuperDrive (which systems produce a disruptive signal). While 400K disks can be formatted using a Hierarchical File System
(HFS) system, they cannot be used as startup disks, or read on an original 128K Macintosh. Unfortunately, when the Macintosh first debuted, a major criticism levied against it was the inadequacy of the single internal floppy disk drive, making the need for two floppy drives a requirement for most purposes. Therefore the external floppy disk drive became critical to the success of the Macintosh.
offering in March 1985. However, it was clear that the Mac's original MFS disk formatting system would be inefficient for such a large drive and 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 & 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. However, based on the success of the 3.5" floppy drive for the Mac, there was no such obstacle in immediately implementing the improved capacity Macintosh drive for the Apple II and was introduced in September 1985, four months before the Mac. While simultaneously Apple finally 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.
and firmware) it will operate as a standard Macintosh 800K drive. This permitted storage hungry Mac users the ability to double their disk capacity 5 months before Apple officially made it available for the Mac. Ironically, though the drive would prove to be significantly faster than the previous 400K drive, it was specifically slowed-down to accommodate the slower 1 MHz processor of the Apple II. It came in the Snow White
-styled case and color to match the Apple IIc and had a pass-through connector for the addition of a second daisy-chained drive. It plugged in directly to the Apple IIc (original required a ROM upgrade) and required a specialized interface card on slotted Apple II's, however would later also work directly with the built-in disk port on the Apple IIc Plus
and Apple IIGS
through backwards compatibility (this was not recommended for the latter two machines due to the drive's slower speed in comparison with the Apple 3.5 Drive). It continued to be sold for use with the Apple IIc and IIe which could not use the subsequent replacement Apple 3.5" drive, until the Apple IIc Plus
redesign in 1988 and Apple II 3.5 Disk Controller Card released in 1991. Apple developed a DuoDisk 3.5 which contained two drives vertically stacked, but never brought it to market. The 3.5" format was never very popular in the Apple II community (excluding the 16-bit Apple IIGS) for which most software was released in the 5.25" format to accommodate the existing installed Disk II
drives.
and a double-sided 800K capacity disk drive, which used the new HFS
disk format providing directories and sub-directories. A revised external drive case was produced to accommodate the slimmer 800K disk mechanism. The Macintosh 800K External Drive (M0131) could only be used with Macintosh models except the original 128K, which could not load the new HFS file format required for use with the drive. However, the new drive did support the older 400K single-sided disks allowing them to be shared. Like the 400K drive before it, Apple's GCR
formatting allowed for variable speed to accommodate a higher storage capacity than its 720K PC counterparts. In addition, the new Sony mechanism was much quieter and significantly faster than its predecessor. Designed primarily to run on Macs with the new 128K ROM
which contained the necessary code to support the drive, it could be used with the older 64K ROMs if the proper software was loaded into the Mac's RAM via the HD20 INIT
installed into the system folder. The drive itself controlled its own speed internally and was no longer dependent on an external signal from the Mac, which was blocked on the early drive mechanisms compatible only with the Macintosh. Later universal mechanisms, first used on the Apple II to accommodate proprietary signals, required special cables to isolate the speed signal from the Mac, to prevent damage to the drive. However, with the increased storage capacity combined with 2-4x the available RAM on the Mac Plus, the external drive was less of a necessity than it had been with its predecessors. Nevertheless, with the only option for adding additional storage being extremely expensive hard drives, Apple increased the ability of the Macintosh SE
introduced a year later, to access up to 3 floppy drives simultaneously (only one of two
Macs to do so).
computer, replaced the beige-colored Macintosh 800K External Drive with a new 800K external drive that 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" includes Apple II-specific features such as a daisy-chain connector which allows two drives to be connected to an Apple II
computer, and the presence of a manual disk eject button. The Macintosh could still only accommodate one external drive, and ignores the ejection button. But, unlike the Macintosh 800K drive, the Apple 3.5" Drive can be used natively with the 64K ROM stock 128K & 512K without the HD20 INIT, (but only with 400K MFS formatted double-sided, or single-sided disks). Designed as a universal external drive replacement, the Apple 3.5" drive was eventually compatible with the remaining Apple II models in production upon the introduction of the Apple IIc Plus and Apple II 3.5 Disk Controller Card for the Apple IIe.
(Modified Frequency Modulation) formatting scheme, incompatible with Apple's own GCR, resulting in a less-expensive drive, but lower 720K capacity. In 1987 a newer and better, MFM-based, "high-density" format was developed which IBM
first introduced in their PS/2
systems, doubling the previous storage capacity. In Apple's pursuit of cross-compatibility with DOS & Windows based systems to attract more business customers, they adopted the new format, thus confirming it as the first industry-wide floppy disk standard. However, Apple could not take advantage of the less expensive fixed speed systems of the IBM-based computers, due to its backward incompatibility with their own variable-speed formats.
, Windows
), allowing the Macintosh to read and write all industry standard floppy disk formatting. 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
(Super Woz 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 the chip was integrated. If the drive was connected to an older Macintosh, Apple IIGS or Apple IIc Plus with the older IWM
(Woz Integrated 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 itself was included internally in every desktop Mac from its introduction until it was eliminated with the introduction of the iMac
in 1998.
, before being discontinued in 1998. This would be the last external floppy drive manufactured by Apple.
Floppy disk
A floppy disk is a disk storage medium composed of a disk of thin and flexible magnetic storage medium, sealed in a rectangular plastic carrier lined with fabric that removes dust particles...
drives manufactured and sold by Apple Computer
Apple Computer
Apple Inc. is an American multinational corporation that designs and markets consumer electronics, computer software, and personal computers. The company's best-known hardware products include the Macintosh line of computers, the iPod, the iPhone and the iPad...
exclusively for the Macintosh
Macintosh
The Macintosh , or Mac, is a series of several lines of personal computers designed, developed, and marketed by Apple Inc. The first Macintosh was introduced by Apple's then-chairman Steve Jobs on January 24, 1984; it was the first commercially successful personal computer to feature a mouse and a...
series of computers introduced in January, 1984. Later, Apple would unify their external drives to work cross-platform between the Macintosh and Apple II
Apple II
The Apple II is an 8-bit home computer, one of the first highly successful mass-produced microcomputer products, designed primarily by Steve Wozniak, manufactured by Apple Computer and introduced in 1977...
product lines, dropping the name "Macintosh" from the drives. Though Apple had been producing external floppy disk drives
Disk II
The Disk II Floppy Disk Subsystem was a 5¼-inch floppy disk drive designed by Steve Wozniak and manufactured by Apple Computer. It was first introduced in 1978 at a retail price of US$495 for pre-order; it was later sold for $595 including the controller card and cable...
prior to 1984, they were exclusively developed for the Apple II, III
Apple III
The Apple III is a business-oriented personal computer produced and released by Apple Computer that was intended as the successor to the Apple II series, but largely considered a failure in the market. Development work on the Apple III started in late 1978 under the guidance of Dr. Wendell Sander...
and Lisa
Apple Lisa
The Apple Lisa—also known as the Lisa—is a :personal computer designed by Apple Computer, Inc. during the early 1980s....
computers using the industry standard 5.25" flexible disk format. The Macintosh external drives were the first to widely introduce Sony
Sony
, commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....
's new 3.5" rigid disk standard commercially and throughout their product line. Apple produced only one external 3.5" drive exclusively for use with the Apple II series called the Apple UniDisk 3.5.
400K
The original Macintosh External Disk Drive (M0130) was introduced with the MacintoshMacintosh 128K
The Macintosh 128K machine, released as the "Apple Macintosh", was the original Apple Macintosh personal computer. Its beige case contained a monitor and came with a keyboard and mouse. An indentation in the top of the case made it easier for the computer to be lifted and carried. It had a selling...
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
Bill Fernandez
Bill Fernandez is a user interface architect who was Apple Computer's first employee when they incorporated in 1977. He was assigned employee number 4. He worked on both the Apple I and Apple II personal computers, and in the 1980s was a member of the Apple Macintosh development team...
was the project manager who oversaw the design and production of the drive. The drive case was designed to match the Macintosh and included the same 400K drive installed inside the Macintosh. Although very similar to the 400K drive which newly replaced Apple's ill-fated Twiggy drive
Apple FileWare
FileWare floppy disk drives and diskettes were designed by Apple Computer as a higher-performance alternative to the Disk II and Disk III floppy systems used on the Apple II and Apple /// personal computers...
in the Lisa, there were subtle differences relating mainly to the eject mechanism. However, all of these drives were labeled confusingly identically. The Macintosh could only support one external drive, limiting the number of floppy disks mounted at once to two. However, 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
Hard Disk 20
The Macintosh Hard Disk 20 was the first hard drive developed by Apple Computer specifically for use with the Macintosh 512K. Introduced on September 17, 1985, it was part of Apple's long awaited solution toward completing the Macintosh Office announced in January 1985...
could accommodate an additional daisy-chained hard drive as well as an external floppy disk. The standard formatted capacity of the drive was 360K, however, Apple employed its GCR
Group Code Recording
In computer science, group code recording refers to several distinct but related encoding methods for magnetic media. The first, used in 6250 cpi magnetic tape, is an error-correcting code combined with a run length limited encoding scheme...
formatting technique which spun the disk at a different rate on the outer edges to increase the total disk storage. Despite the greater storage capacity, the drive could not be used on the Apple II. Nor could the Lisa accommodate it as an external drive, despite being originally offered with two 871K drives. These drives only support the original Macintosh File System
Macintosh File System
Macintosh File System is a volume format created by Apple Computer for storing files on 400K floppy disks. MFS was introduced with the Macintosh 128K in January 1984....
(MFS), though they can be used on any Macintosh which does not also support a SuperDrive (which systems produce a disruptive signal). While 400K disks can be formatted using a Hierarchical File System
Hierarchical File System
Hierarchical File System is a file system developed by Apple Inc. for use in computer systems running Mac OS. Originally designed for use on floppy and hard disks, it can also be found on read-only media such as CD-ROMs...
(HFS) system, they cannot be used as startup disks, or read on an original 128K Macintosh. Unfortunately, when the Macintosh first debuted, a major criticism levied against it was the inadequacy of the single internal floppy disk drive, making the need for two floppy drives a requirement for most purposes. Therefore the external floppy disk drive became critical to the success of the Macintosh.
800K
By early 1985, it was clear that the Macintosh needed additional storage space, in particular a hard drive. Apple announced their first hard driveHard Disk 20
The Macintosh Hard Disk 20 was the first hard drive developed by Apple Computer specifically for use with the Macintosh 512K. Introduced on September 17, 1985, it was part of Apple's long awaited solution toward completing the Macintosh Office announced in January 1985...
offering in March 1985. However, it was clear that the Mac's original MFS disk formatting system would be inefficient for such a large drive and Apple quickly began adopting for the Mac the hierarchical based SOS filing system introduced with the Apple III
Apple III
The Apple III is a business-oriented personal computer produced and released by Apple Computer that was intended as the successor to the Apple II series, but largely considered a failure in the market. Development work on the Apple III started in late 1978 under the guidance of Dr. Wendell Sander...
and long since implemented in ProDOS for the Apple II series & the Lisa
Apple Lisa
The Apple Lisa—also known as the Lisa—is a :personal computer designed by Apple Computer, Inc. during the early 1980s....
. 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. However, based on the success of the 3.5" floppy drive for the Mac, there was no such obstacle in immediately implementing the improved capacity Macintosh drive for the Apple II and was introduced in September 1985, four months before the Mac. While simultaneously Apple finally 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 3.5" drive (A2M2053) for the Apple II series utilizing Sony's new 800K drive mechanism which would not be released for the Macintosh until 4 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 drive mechanism that was to be used in the Macintosh. However, with the internal circuit board bypassed or removed (which consisted of its own CPU, RAMRam
-Animals:*Ram, an uncastrated male sheep*Ram cichlid, a species of freshwater fish endemic to Colombia and Venezuela-Military:*Battering ram*Ramming, a military tactic in which one vehicle runs into another...
and firmware) it will operate as a standard Macintosh 800K drive. This permitted storage hungry Mac users the ability to double their disk capacity 5 months before Apple officially made it available for the Mac. Ironically, though the drive would prove to be significantly faster than the previous 400K drive, it was specifically slowed-down to accommodate the slower 1 MHz processor of the Apple II. It came in the Snow White
Snow White design language
The Snow White design language was an industrial design language developed by Hartmut Esslinger's Frog Design. Used by Apple Computer from 1984 to 1990, the scheme has vertical and horizontal stripes for decoration, ventilation, and the illusion that the computer enclosure is smaller than it...
-styled case and color to match the Apple IIc and had a pass-through connector for the addition of a second daisy-chained drive. It plugged in directly to the Apple IIc (original required a ROM upgrade) and required a specialized interface card on slotted Apple II's, however would later also work directly with the built-in disk port on the Apple IIc Plus
Apple IIc Plus
The Apple IIc Plus is the sixth and final model in the Apple II line of personal computers, produced by Apple Computer. The "Plus" in the name was a reference to the additional features it offered over the original portable Apple IIc, such as greater storage capacity , increased processing speed,...
and Apple IIGS
Apple IIGS
The Apple , the fifth and most powerful model in the Apple II series of personal computers produced by Apple Computer. The "GS" in the name stands for Graphics and Sound, referring to its enhanced graphics and sound capabilities, both of which greatly surpassed previous models of the line...
through backwards compatibility (this was not recommended for the latter two machines due to the drive's slower speed in comparison with the Apple 3.5 Drive). It continued to be sold for use with the Apple IIc and IIe which could not use the subsequent replacement Apple 3.5" drive, until the Apple IIc Plus
Apple IIc Plus
The Apple IIc Plus is the sixth and final model in the Apple II line of personal computers, produced by Apple Computer. The "Plus" in the name was a reference to the additional features it offered over the original portable Apple IIc, such as greater storage capacity , increased processing speed,...
redesign in 1988 and Apple II 3.5 Disk Controller Card released in 1991. Apple developed a DuoDisk 3.5 which contained two drives vertically stacked, but never brought it to market. The 3.5" format was never very popular in the Apple II community (excluding the 16-bit Apple IIGS) for which most software was released in the 5.25" format to accommodate the existing installed Disk II
Disk II
The Disk II Floppy Disk Subsystem was a 5¼-inch floppy disk drive designed by Steve Wozniak and manufactured by Apple Computer. It was first introduced in 1978 at a retail price of US$495 for pre-order; it was later sold for $595 including the controller card and cable...
drives.
Macintosh 800K External Drive
In January, 1986, Apple introduced the Macintosh PlusMacintosh Plus
The Macintosh Plus computer was the third model in the Macintosh line, introduced on January 16, 1986, two years after the original Macintosh and a little more than a year after the Macintosh 512K, with a price tag of US$2599...
and a double-sided 800K capacity disk drive, which used the new HFS
Hierarchical File System
Hierarchical File System is a file system developed by Apple Inc. for use in computer systems running Mac OS. Originally designed for use on floppy and hard disks, it can also be found on read-only media such as CD-ROMs...
disk format providing directories and sub-directories. A revised external drive case was produced to accommodate the slimmer 800K disk mechanism. The Macintosh 800K External Drive (M0131) could only be used with Macintosh models except the original 128K, which could not load the new HFS file format required for use with the drive. However, the new drive did support the older 400K single-sided disks allowing them to be shared. Like the 400K drive before it, Apple's GCR
Group Code Recording
In computer science, group code recording refers to several distinct but related encoding methods for magnetic media. The first, used in 6250 cpi magnetic tape, is an error-correcting code combined with a run length limited encoding scheme...
formatting allowed for variable speed to accommodate a higher storage capacity than its 720K PC counterparts. In addition, the new Sony mechanism was much quieter and significantly faster than its predecessor. Designed primarily to run on Macs with the new 128K ROM
Read-only memory
Read-only memory is a class of storage medium used in computers and other electronic devices. Data stored in ROM cannot be modified, or can be modified only slowly or with difficulty, so it is mainly used to distribute firmware .In its strictest sense, ROM refers only...
which contained the necessary code to support the drive, it could be used with the older 64K ROMs if the proper software was loaded into the Mac's RAM via the HD20 INIT
Hard Disk 20
The Macintosh Hard Disk 20 was the first hard drive developed by Apple Computer specifically for use with the Macintosh 512K. Introduced on September 17, 1985, it was part of Apple's long awaited solution toward completing the Macintosh Office announced in January 1985...
installed into the system folder. The drive itself controlled its own speed internally and was no longer dependent on an external signal from the Mac, which was blocked on the early drive mechanisms compatible only with the Macintosh. Later universal mechanisms, first used on the Apple II to accommodate proprietary signals, required special cables to isolate the speed signal from the Mac, to prevent damage to the drive. However, with the increased storage capacity combined with 2-4x the available RAM on the Mac Plus, the external drive was less of a necessity than it had been with its predecessors. Nevertheless, with the only option for adding additional storage being extremely expensive hard drives, Apple increased the ability of the Macintosh SE
Macintosh SE
The Macintosh SE was a personal computer manufactured by Apple between March 1987 and October 1990. This computer marked a significant improvement on the Macintosh Plus design and was introduced by Apple at the same time as the Macintosh II....
introduced a year later, to access up to 3 floppy drives simultaneously (only one of two
Macintosh Portable
The Macintosh Portable was Apple Inc.'s first attempt at making a battery-powered portable Macintosh personal computer that held the power of a desktop Macintosh...
Macs to do so).
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), released in unison with the Apple IIGSApple IIGS
The Apple , the fifth and most powerful model in the Apple II series of personal computers produced by Apple Computer. The "GS" in the name stands for Graphics and Sound, referring to its enhanced graphics and sound capabilities, both of which greatly surpassed previous models of the line...
computer, replaced the beige-colored Macintosh 800K External Drive with a new 800K external drive that 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" includes Apple II-specific features such as a daisy-chain connector which allows two drives to be connected to an Apple II
Apple II
The Apple II is an 8-bit home computer, one of the first highly successful mass-produced microcomputer products, designed primarily by Steve Wozniak, manufactured by Apple Computer and introduced in 1977...
computer, and the presence of a manual disk eject button. The Macintosh could still only accommodate one external drive, and ignores the ejection button. But, unlike the Macintosh 800K drive, the Apple 3.5" Drive can be used natively with the 64K ROM stock 128K & 512K without the HD20 INIT, (but only with 400K MFS formatted double-sided, or single-sided disks). Designed as a universal external drive replacement, the Apple 3.5" drive was eventually compatible with the remaining Apple II models in production upon the introduction of the Apple IIc Plus and Apple II 3.5 Disk Controller Card for the Apple IIe.
1.44MB
Following the success of the Macintosh implementation of the 3.5" format, the format was adopted widely by the personal computer industry. However they adopted a different MFMModified Frequency Modulation
Modified Frequency Modulation, commonly MFM, is a line coding scheme used to encode the actual data-bits on most floppy disk formats, hardware examples include Amiga, most CP/M machines as well as IBM PC compatibles. Early hard disk drives also used this coding.MFM is a modification to the original...
(Modified Frequency Modulation) formatting scheme, incompatible with Apple's own GCR, resulting in a less-expensive drive, but lower 720K capacity. In 1987 a newer and better, MFM-based, "high-density" format was developed which IBM
IBM
International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
first introduced in their PS/2
IBM Personal System/2
The Personal System/2 or PS/2 was IBM's third generation of personal computers. The PS/2 line, released to the public in 1987, was created by IBM in an attempt to recapture control of the PC market by introducing an advanced proprietary architecture...
systems, doubling the previous storage capacity. In Apple's pursuit of cross-compatibility with DOS & Windows based systems to attract more business customers, they adopted the new format, thus confirming it as the first industry-wide floppy disk standard. However, Apple could not take advantage of the less expensive fixed speed systems of the IBM-based computers, due to its backward incompatibility with their own variable-speed formats.
Apple FDHD Drive
Later re-named the Apple SuperDrive (G7287), the Apple FDHD Drive (Floppy Disk High Density) was introduced in 1988 as Apple's first 1.44MB high density double-sided 3.5" floppy disk. It supported all of Apple's 3.5" floppy disk formats as well as all standard PC formats (e.g. MS-DOSMS-DOS
MS-DOS is an operating system for x86-based personal computers. It was the most commonly used member of the DOS family of operating systems, and was the main operating system for IBM PC compatible personal computers during the 1980s to the mid 1990s, until it was gradually superseded by operating...
, Windows
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
), allowing the Macintosh to read and write all industry standard floppy disk formatting. 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
Disk controller
The disk controller is the circuit which enables the CPU to communicate with a hard disk, floppy disk or other kind of disk drive.Early disk controllers were identified by their storage methods and data encoding. They were typically implemented on a separate controller card...
(Super Woz 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 the chip was integrated. If the drive was connected to an older Macintosh, Apple IIGS or Apple IIc Plus with the older IWM
Disk controller
The disk controller is the circuit which enables the CPU to communicate with a hard disk, floppy disk or other kind of disk drive.Early disk controllers were identified by their storage methods and data encoding. They were typically implemented on a separate controller card...
(Woz Integrated 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
Macintosh Classic II
The Apple Macintosh Classic II replaced the Macintosh SE/30 in the compact Macintosh line in 1991. Like the SE/30, the Classic II was powered by a 16 MHz Motorola 68030 CPU and 40 or 80 MB hard disk, but in contrast to its predecessor, it was limited by a 16-bit data bus and a 10 MB memory...
and was discontinued shortly thereafter. The drive itself was included internally in every desktop Mac from its introduction until it was eliminated with the introduction of the iMac
IMac
The iMac is a range of all-in-one Macintosh desktop computers built by Apple. It has been the primary part of Apple's consumer desktop offerings since its introduction in 1998, and has evolved through five distinct forms....
in 1998.
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 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. The external case was finally revised in 1997 and renamed Macintosh PowerBook External Floppy Drive, for use exclusively with the PowerBook 2400cPowerBook 2400c
The PowerBook 2400c is a subnotebook in Apple Computer's PowerBook range of Macintosh computers, weighing . Manufacturing was contracted to IBM. In a return to the PowerBook 100 form factor, It was introduced in May 1997 as a late replacement for the PowerBook Duo 2300c, which had been the last of...
, before being discontinued in 1998. This would be the last external floppy drive manufactured by Apple.
See also
- Disk IIDisk IIThe Disk II Floppy Disk Subsystem was a 5¼-inch floppy disk drive designed by Steve Wozniak and manufactured by Apple Computer. It was first introduced in 1978 at a retail price of US$495 for pre-order; it was later sold for $595 including the controller card and cable...
- List of Apple drives
- History of the floppy disk
- Timeline of Apple productsTimeline of Apple productsThis timeline of Apple products is a list of all stand-alone Apple II, Macintosh, and other computers, as well as computer peripherals, expansion cards, software, ancillary products, and consumer electronics sold by Apple Inc...
- List of products discontinued by Apple Inc.
External links
- Macintosh: Support for External Floppy Drives (at Apple support site)
- vintagemacworld.com Apple External Drives