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Apple III
From Wikipedia, the free encyclopedia
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| Apple III | |
|---|---|
| Manufacturer | Apple Computer |
| Introduced | May 1980 |
| Discontinued | April 1984 |
| Price | US$3,500 |
| CPU | Synertek 6502A, 2 MHz |
| RAM | 128 KiB, expandable to 512 KiB, |
| OS | Apple Sophisticated OS (SOS) |
The Apple III was a personal computer aimed at business users, manufactured and sold by Apple from May, 1980 until its discontinuation on April 24, 1984. Its predecessor, the better-known Apple II, was designed by Apple co-founder Steve Wozniak. Design work on the Apple III started in late 1978 under the guidance of Dr. Wendell Sander. It had the internal code name of "Sara", named after Sander's daughter.
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The Apple III was designed to be a business computer. It featured an advanced operating system called SOS (the Sophisticated Operating System) and a new BASIC interpreter, "Apple /// Business BASIC" (an implementation of UCSD Pascal was also offered for more structured programming). Other features included an 80-column display with upper and lowercase characters, a numeric keypad, support for a real-time clock, 6-bit (DAC) audio, 16-color graphics, a hierarchical file system, and the ability to emulate a 48 KiB Apple II+. There was a built-in 140 kB 5.25" floppy disk drive, with up to three additional external "Disk ///" floppy disk drives and a ProFile 5 or 10 megabyte hard disk drive available as options. Microsoft developed an add-in "Softcard" that allowed the Apple III to run CP/M, which was actually sold as an Apple product.
The Apple III was powered by a 2 MHz SynerTek 6502A 8-bit CPU and, like some of the more advanced machines in the Apple II family, used bank switching techniques to address up to 256 KiB of memory (512 KiB with a third-party upgrade).
The Apple III was the first Apple product that allowed the user to choose both a screen font and a keyboard layout:either QWERTY or Dvorak. These choices could not be changed while programs were running, unlike the Apple IIc, with a Keyboard switch directly above the keyboard, allowing switching on the fly, and most recent versions of MacOS, which have a Keyboard menu on the menu bar, allowing on-the-fly switching.
The Apple III had a System Utilities program, which allowed system reconfiguration and file manipulation. Another program, Selector III, was designed to integrate with the System Utilities program and launch various applications. In some ways, it was a precursor to the Macintosh Finder. However, Apple decided not to finish this project, and the engineers and writers working on the project bought the right to market Selector II to Apple III owners for a nominal fee. However, another company, Quark Software, developed a competing product, Catalyst, with a program-switching capability, a cruder interface, and support for copy-protection, which enabled companies to license users to run programs from a hard disk without worrying that their precious software might be backed up or stolen. When Apple decided to bundle Catalyst with its new ProFile hard disk, Quark celebrated--it eventually grew into a major software vendor with Quark Xpress); and the Selector III's developers quietly dissolved their company.
At Steve Jobs' insistence, the machine did not include a cooling fan—the metal case was supposed to act as a heat sink, despite not being designed for this purpose. Furthermore, the case itself was too small to properly accommodate the III's internals, and Apple skimped on gold-plating the electrical contacts. The result was an unmitigated disaster. The system would overheat so severely that the motherboard would warp in its tight confines, and thermal expansion would actually push the DIP chips out of their sockets. One popular anecdote about the Apple III is probably better remembered than the machine itself: in a technical bulletin, customers were actually instructed to lift the machine three inches (76 mm) and drop it in order to reseat the chips. Another problem was that the circuit board used a "fineline" technology that was not fully mature, with narrow, closely spaced traces. When chips were "stuffed" into the board and wave-soldered, solder bridges would form between traces that were not supposed to be connected. This caused numerous short circuits, which required hours of costly diagnosis and hand rework to fix. Apple designed a new circuit board, with more layers and normal-width traces. It was designed by one designer on a huge drafting board, rather than a costly CAD-CAM system used for the previous board, and it worked.
Some of the features and codebase of the Sophisticated Operating System made their way into the Apple II's ProDOS and GS/OS operating systems, as well as those of the Lisa and Macintosh.
For a variety of reasons, the Apple III was a commercial failure. With a starting price of about $3,500 US, it was more expensive than many of the CP/M-based business computers that were available at the time. The Apple III's software library was very limited, and whilst sold as an Apple II compatible, the emulation that made this possible was intentionally hobbled, thus it could not make use of the advanced III features (specifically 64 KiB RAM or higher, required by a large number of Apple II software titles based on PASCAL) which limited its usefulness.
Far more importantly, the machine was plagued by numerous hardware and software bugs. The real time clock, the first in an Apple computer, would fail after prolonged use. This chip, which was made by National Semiconductor, was an example of a recurrent problem. Semiconductor purchase contracts allowed a vendor 30 days to replace defective parts. It was assumed that a vendor would test parts before shipping them, but this was not required. National had a reputation for knowingly shipping bad parts, confident that they could do another production run before they had to send replacements. This was not a problem for customers who put chips in sockets and had extensive repair facilities. However, Apple was soldering chips directly to boards and could not easily test a board to find a single bad chip. Eventually, Apple solved this problem by deleting the real-time clock from the specification, rather than putting in a working clock chip.
In the end, Apple "ate" the first 14,000 Apple III machines: Those brave customers who had bought them were given brand new machines, with new circuit boards. These did not constitute a new model: it was deemed warranty service.
An improved version, the Apple III Plus, was introduced in December 1983. The III Plus fixed the hardware problems of the original III, included 256 KiB RAM, built-in clock, video interlacing, and featured a keyboard in the style of the Apple IIe. However, not even the new "allow me to reintroduce myself" campaign could salvage the III's reputation. Possibly more relevant in the long run was the fact that the III was essentially an enhanced Apple II—newest heir to a line of 8-bit machines dating back to 1976. The year after the III was originally released, IBM unveiled its PC—a completely new 16-bit design soon available in a wide range of inexpensive clones. The business market moved rapidly towards the IBM machines and, in September 1985, the Apple III line was discontinued, having sold only about 65,000 systems. Apple co-founder Steve Wozniak stated that the primary reason for the Apple III's failure was that the system was designed by Apple's marketing department, unlike Apple's previous engineering-driven projects.[1]
- Apple III chaos (Cortland), Joshua Coventry, Low End Mac (2006)
- ^ Wozniak, S. G. (2006), iWoz: From Computer Geek to Cult Icon: How I Invented the Personal Computer, Co-Founded Apple, and Had Fun Doing It. W. W. Norton & Company. ISBN 0-393-06143-4.