Apple II family
The Apple II family was the first series of microcomputers made by Apple
Computer, in the late 1970s and early-to-mid 1980s. Completely different
from Apple's later Macintosh computers, the Apple II was a predominantly
8-bit architecture.
The progenitor was the Apple I, which was a hand-built machine sold to
hobbyists. It was never produced in quantity, but pioneered many of the
features making the Apple II a success. The first large-scale production
computer was the Apple II. It became popular with home users, as well as
occasionally being sold to business users, particularly after the release of
the first ever spreadsheet on any computer, VisiCalc. See the computing
timeline for dates of Apple II family model releases: the 1977 Apple II, and
its younger siblings, the II Plus, IIe, IIc and IIGS.
History
The original Apple II
The first Apple II came with a MOS Technologies 6502 microprocessor running
at 1 MHz, 4 KB of RAM, an audio cassette interface, and the Integer BASIC
programming language built into the ROMs. The video controller displayed 24
lines by 40 columns of upper-case-only text on the screen, with NTSC
composite video output for display on a monitor, or on a TV set by way of an
RF modulator. Users could save and retrieve programs and data on audio
cassettes; other programming languages, games, applications and other
software were available on cassette too.
Later, an external 5.25" floppy disk drive, the Disk II, with controller
card that plugged into one of the computer's slots, enabled much more
convenient data storage and retrieval. This disk drive interface created by
Steve Wozniak is still regarded as an engineering design marvel. The
controller card had very little hardware support, relying on software timing
loops instead to provide the necessary encoding; the controller also used a
form of group code recording, which was simpler and easier to implement in
software than the more common MFM. That reduced the overall cost
significantly, leaving the total system price low enough for home users. It
also made it easy for proprietary software developers to make the media on
which their applications shipped hard to copy by using tricks such as
changing the low-level sector format or even stepping the drive's head
between the tracks; however, other groups eventually sold software such as
Copy II Plus and Locksmith that could foil such restrictions.
Wozniak's open design and the Apple's multiple expansion slots permitted a
wide variety of third-party devices to expand the capabilities of the
machine. Serial controllers, improved display controllers, memory boards,
hard disks, and networking components were available for this system in its
day. There were also emulator cards, such as the Z80 card which permitted
the Apple to switch to the Z80 processor and run a multitude of programs
developed under the CP/M operating system such as the dBase II database and
the WordStar word processing program. There was also a third-party 6809 card
with which one could run OS-9 Level One. The Mockingboard sound card greatly
improved the audio capabilities of the Apple. Accelerator boards were
eventually created which would double or quadruple the computer's speed.
The Family Grows
The Apple II was eventually superseded by the Apple II Plus, that included
the Applesoft BASIC programming language (which added support for
floating-point arithmetic but sacrificed integer performance in the process)
in ROM (previously available as an upgrade) and had a total of 48 kilobytes
of RAM, expandable to 64 KB through a "language card" that let users quickly
switch between "INT" (Integer) and "FP" (Applesoft) dialects of BASIC (but
destroying any unsaved program in the process). Addition of the language
card also enabled the use of UCSD Pascal and FORTRAN 77 compilers, released
for the Apple at that time.
This was followed by the Apple IIe, a cost-reduced version, that used newer
chips to reduce the overall component count. It also displayed both upper
and lowercase letters and had 64 KB of RAM expandable to 128 KB. The IIe
could also display high resolution text (80 columns) with an add-in 80
column card. The IIe was probably the most popular Apple II and was widely
considered the "workhorse" of the line.
About the same time, a computer called the Apple III was produced. This was
marketed to business users and was never successful. Steve Wozniak has been
quoted as saying that the Apple III had a 100% failure rate.
Apple later produced their first portable Apple II called the Apple IIc. It
used the updated 65C02 processor and featured onboard controllers for common
devices such as disk drives, modems, etc., that previously required adapter
cards. However, due to its compact design, the Apple IIc had limited
expandability. Apple later licensed accelerator technology from Zip
Technologies to produce the 4 MHz Apple IIc+, which also had a built-in 3.5"
floppy drive in place of the older 5.25". The Apple IIc was codenamed the
"Lolly" in certain internal and prerelease documents.
Shortly after introducing the Apple IIc, Apple produced an Enhanced Apple
IIe that used the 65C02 processor. A final version of the IIe known as the
Platinum Apple IIe was introduced later; it added a numeric keypad and used
a different color of case from earlier IIe versions.
The final member of the line was the Apple IIGS computer, released in 1986.
The IIGS featured a 2.8 MHz 65C816 processor with 16-bit registers, larger
address space with more memory, better color, more peripherals (switchable
between IIe-style card slots and IIc-style onboard controllers), and a user
interface derived from Mac OS.
Apple's Macintosh product line eclipsed Apple II sales around 1986. Apple
did continue to sell and support the IIe and IIGS until 1992-1993, largely
due to their use in schools.
Life After Death
Nowadays, even a PC running Microsoft Windows can emulate the important
Apple II models with emulator software such as AppleWin by copying the disk
through a serial line. However emulators cannot run software on
copy-restricted media unless somebody "cracks," or removes the copy
restrictions from, the software. Numerous disk images for Apple II software
are available free over the Internet. There is a movement afoot to convince
the copyright holders of classic Apple II software to officially allow
unrestricted free distribution of their software.
Impact
It is difficult to estimate the gigantic impact that the Apple II family of
computers has had on world business and, especially, the technology
industry. The Apple II was the first computer that most people had ever
seen, and it was affordable for middle-class families. Its popularity
enabled the entire computer game market; the educational software market; a
boom in the word processor and computer printer market; and the absolute
"killer app" for business: VisiCalc, the first spreadsheet. VisiCalc alone
sold many Apple II's to all kinds of business people. On the other hand, the
success in the home market inspired the creation of many other inexpensive
home computers such as the VIC-20 (1980) and Commodore 64 (1982), which
through their significantly lower price pont introduced computers to several
million more home users (grabbing some of Apple's market share in the process).
The success of the Apple II also goaded IBM to create the IBM PC, which was
then purchased by middle managers in all lines of business in order to run
spreadsheet and word processor software (which at first was ported from the
Apple II versions, and later inspired whole new application software
franchises). The strong popularity of these PCs and their clones then
transformed business again with LAN applications such as e-mail and the
later use of PCs to access the USENET and the WWW.
One valuable lesson from the first Apple II computers was the importance of
an open architecture to a particular platform. The computer's slots,
allowing any peripheral card to take control of the bus, enabled an
independent industry of card manufacturers who together created a flood of
products that let users build systems that were far more powerful and useful
(at a lower cost) than could possibly have occurred if Apple had kept its
system proprietary. Apple failed to create an open architecture with the
initial Macintosh models, and this is widely seen as having hobbled its
potential success. IBM did create its IBM PC with an open architecture,
which helped its wild success, though in the end IBM was unable to control
the creation of clones, and has been eclipsed by competitors such as Dell,
Compaq/Hewlett-Packard, and Gateway.
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