Apple II
From Retrocomputing Wiki
| Apple II | |
|---|---|
| Manufacturer | Apple Computer |
| Type | Home computer |
| Released | June 1977 |
| Introductory price | US$1,298 (4 KB), $2,638 (48 KB) |
| Discontinued | 1979 (replaced by the Apple II Plus) |
| CPU | MOS Technology 6502 at 1.023 MHz |
| Memory | 4 KB, expandable to 48 KB |
| Storage | Cassette, Disk II 5.25-inch floppy drive (from 1978) |
| Display | 40 × 24 text; 280 × 192 high-resolution graphics |
| Sound | 1-bit speaker |
| Operating system | Integer BASIC in ROM; Apple DOS from disk |
The Apple II is an 8-bit personal computer designed by Steve Wozniak and introduced by Apple Computer at the West Coast Computer Faire in April 1977. It was one of the first personal computers to be sold fully assembled in a plastic case, with a keyboard and colour graphics, and together with the Commodore PET and the TRS-80 it is often counted as one of the "1977 trinity" of ready-made home computers. The Apple II and its successors were made for sixteen years and were Apple's main source of income until the late 1980s.
Contents |
[edit] Development
Wozniak had already designed the Apple I, a bare circuit board sold to hobbyists in 1976. The Apple II was a much more complete machine. Its colour video was generated with very few chips by taking advantage of the way NTSC television signals work, and it had eight expansion slots on the motherboard, which Wozniak insisted on against Steve Jobs's wishes.
Mike Markkula invested $250,000 in the company and helped write its business plan, and Rod Holt designed a switching power supply that did not need a cooling fan. The beige plastic case was designed by Jerry Manock.
[edit] Hardware
The Apple II uses a MOS Technology 6502 at just over 1 MHz. The base model shipped with 4 KB of RAM and could be expanded to 48 KB on the motherboard. Wozniak's Integer BASIC was built into ROM, so the computer was ready to program as soon as it was switched on.
The video hardware offers a 40 × 24 upper-case text mode, a low-resolution graphics mode of 40 × 48 blocks in 16 colours and a high-resolution mode of 280 × 192 pixels. On the earliest boards high-resolution mode showed four colours (black, white, green and violet); later boards added orange and blue. Sound comes from a single speaker that the program clicks on and off directly.
[edit] Disk II
In 1978 Apple released the Disk II floppy drive and controller card, also designed by Wozniak, which used far fewer chips than other controllers of the time. With DOS 3.3 (1980) a disk holds 140 KB. The Disk II made the Apple II much more practical for business use and was an important reason for its success.
[edit] VisiCalc
In 1979 Personal Software released VisiCalc, the first spreadsheet program for personal computers, written by Dan Bricklin and Bob Frankston. For more than a year it was only available on the Apple II, and many businesses bought the computer just to run it. It is often called the first "killer application".
[edit] Successors
- Apple II Plus (1979): Applesoft BASIC (licensed from Microsoft) in ROM, 48 KB as standard.
- Apple IIe (January 1983): upper and lower case, 64 KB, fewer chips. The longest-lived model, sold until 1993.
- Apple IIc (April 1984): a compact, semi-portable version with a built-in disk drive.
- Apple IIGS (September 1986): a 16-bit machine with a 65C816 processor and a much better sound chip, compatible with older Apple II software.
- Apple IIc Plus (1988): the last new model.
Apple stopped selling the Apple IIe in November 1993.
