The Apple IIgs was the Apple II platform's last hurrah before it was abandoned entirely in favor of the Macintosh. IIgs users were a fierce bunch, resulting in one of the longest lived 'dead' computer platforms in history (even more so than Amiga). Its cult following sprouted from a mix of brilliantly advanced technology and brand loyalty. It took years for Macs to catch up with Apple IIgs sound capabilities, and excellent graphics were achieved by means of a few clever tricks. Add-on companies such as Applied Engineering kept the IIgs alive well into the 90s. Rumour has it some people still run them today.
Tech Specs
Release Date: September, 1986
CPU: Western Design Center 65SC816
CPU Speed: 1mhz / 2.8mhz
Bus Speed: 1mhz
Ram: 128k on-board, expandable to 8MB
Video RAM: 32k
Video Modes: Old Apple modes plus new super high-res modes (see below)
Expandability: 7 expansion slots
Technological Innovation
The most impressive part of the IIgs was its built-in Ensoniq synthesizer, capable of reproducing 15 stereo voices and had 64k of on-chip memory. This feature alone gave the Apple IIgs the most sophisticated audio capabilities of any computer well into the 90s. These days we take computer audio for granted, so it's hard to imagine the amazement at hearing this kind of sound come out of a computer in 1986. Interestingly the inclusion of the synthesizer caused a lawsuit by the now-defunct Apple Records which resulted in Apple steering well clear of any built-in audio enhancements for a number of years (until the lawsuit was revived with the inclusion of a CD-ROM drive, hence the name of the Apple sound Sosumi).
In order to offer the complete cutting-edge package, Apple engineers endowed the new machine with several new graphics modes dubbed super hi-res. At the time of development, monitors supporting more than 200 lines were expensive, so new resolutions of 320x200 and 640x200 were chosen, giving the IIgs a oblong quality to its pixels in the highest resolution. The IIgs video controller could use only a 16-color palette which was specified from a 12-bit color gamut (choose 16 out of 4096 possible colors). Apple engineers employed some clever tricks to squeeze out lots of colors from the three most interesting modes:
- 320x200 w/ 256 colors - The video controller had memory for 16 palettes even though only one could be used at a time. By specifying a different palette for each line, 256 colors could be achieved with relatively high performance.
- 320x200 w/ 3200 colors - Swapping out palettes as the controller refreshes all 200 lines results in a possible 3200 of 4096 colors. Of course, swapping palettes in and out of memory every line could be slow, so this mode was primarily useful for viewing static images (but damn it looked fine).
- 640x200 w/ 16 dithered colors - Because of limitations on memory by doubling the number of columns, 640x200 is limited to 4 colors. Those clever bastards at Apple decided to add a mode where each column alternates between two 4-color palettes, resulting in 16 dithered colors.
The IIgs also introduced the Apple Desktop Bus (ADB) which became standard on all Macs between the release of the Mac SE (1987) and early Mac G3s (1997). The easy expandability was probably the most sorely missed feature for those who migrated to the Mac platform. Additionally the IIgs was the last Apple machine with a command line interface and a built-in compiler until the advent of Mac OS X (hackers rejoice).
Early Development
The major hurdle that Apple had to face in the early 80s was that 6502 chip on which the Apple II was based could only address 64k of memory directly. Apple management invested heavily in many hardware development projects centered around different chips in search of the next big thing. The foundation for the Apple IIgs could not be laid until 1983 when Western Design Center was supposed to make samples of the new 16-bit 65816 chip available to Apple. Unfortunately delivery problems with the new chips and internal political troubles at Apple stifled development and the project was temporarily dropped with focus shifting to the new Macintosh platform. It wasn't until later that year when the Apple II Forever event revived interest in the Apple II platform that the Apple IIgs project was truly begun in earnest headed up by Steve Wozniak, Dan Hillman, and Jay Rickard.
The Cult
The most amazing thing about the Apple IIgs was how much it improved over its life cycle. In the beginning the IIgs was little more than a glorified Apple IIe. It took time for knowledge of the IIgs capabilities to percolate through the developer community. But once the audio and video demos started to roll out from Apple hackers, the software and hardware extensions began pushing the envelope in ways PC users could only dream of. While the Mac was 'the computer for the rest of us', the IIgs was an audio/video geek's wet dream.
The IIgs enjoyed early success, but lack of marketing and support from Apple relegated it to obsolescence. Due to this lack of support, the IIgs cult emerged as an underground society. Schools with IIgses never even ran GS/OS. As far as the casual user knew, all Apple IIs had at most 4 sinfully ugly colors in their graphical mode. In reality, the IIgs had the best graphics*, the best audio, and an increasing number of the best games of any personal computers in the 80s. After 1990, the IIgs became even more specialized as hard-core users upgraded with the latest Applied Engineering cards, and new software pushing the technological envelope continued to come from the hacker community. Eventually Windows and Macintosh capabilities surpassed the IIgs, and the community inevitably faded. Still, the IIgs was a brilliant closing note for the Apple II platform. It will long be remembered fondly by many.
*the Amiga had 640x400 resolutions and a static graphics mode utilizing the full 4096 12-bit color palette, and thus had technically superior graphics. However, it had only half the video memory, and fewer special video modes. Thus it could only use 32 colors in dynamic video whereas the IIgs could utilize 256, at least until newer video cards appeared for the Amiga. (Thanks Ulkesh for pointing out Amiga's superiority.)
Sources
http://www.apple-history.com/frames/?&page=gallery&model=aIIgs
http://www.old-computers.com/museum/computer.asp?c=71
http://apple2history.org/history/ah10.html