Apple IIGS
[Vin144]
The Apple IIgs (1986-1992) represents a pivotal transitional machine in computing history as Apple’s first computer with a color GUI, arriving six months before the Macintosh II, and featuring revolutionary multimedia capabilities that bridged 8-bit and 16-bit architectures while maintaining full backward compatibility with the entire Apple II software library. Its claim to fame lies in its exceptional Ensoniq 5503 wavetable synthesis chip with 32 oscillator channels producing 16-voice stereo audio and 64KB of dedicated sound RAM, arguably the best sound of any personal computer of its era, combined with “Super High-Resolution” graphics supporting up to 4,096 colors from a 12-bit palette, displaying up to 3,200 colors simultaneously through palette manipulation. Despite moderate commercial success with approximately 1-1.5 million units sold over six years, the company deliberately clocked its capable 65C816 16-bit processor at only 2.8 MHz, despite certification for 4+ MHz, to avoid cannibalizing Macintosh sales, exemplifying how corporate strategy can constrain technical innovation, a critical lesson in computing history about business decisions trumping engineering excellence
- Manufacturer: Apple Computer Inc.
- Released: 1986
- Type: Personal Computer
- Cost at release (no monitor): USD $999 (CAD ~$3,500 adjusted for inflation)
- Cost with peripherals: CAD $6,500 (adjusted for inflation)
- MIPS: 0.22 MIPS (millions of instructions per second). This relatively modest performance was due to Apple’s deliberate decision to limit the clock speed despite the processor being certified for 4+ MHz operation.
Hardware Specifications
- CPU: Western Design Center WDC 65C816 (16-bit)
- RAM (Original 1986): 128 KB expandable to 8 MB
- ROM (Original): 128 KB
- Video Controller: Custom Video Graphics Controller (VGC)
- Sound Chip: Ensoniq 5503 digital oscillator chip
- Expansion Slots: Seven Apple II Bus slots (50-pin card-edge)
- Floppy Drives: Support for 3.5″ (800 KB) and 5.25″ (140 KB) formats
- Hard Drive Support: SCSI interface available via expansion card
- Weight: 4.1 kg
Operating System & Programming Languages
- O/S:
- Native 16-bit Operating Systems:
- ProDOS 16 (1986-1988): The initial operating system shipped with the IIgs, based on the 8-bit ProDOS but modified for 16-bit hardware. However, it was written primarily in 8-bit code and didn’t fully utilize the IIgs’s capabilities.
- GS/OS (System Software 4.0-6.0.1, 1988-1993): Apple’s true 16-bit operating system written entirely in 65816 code. It featured a Macintosh-like GUI, resource forks, device drivers, AppleShare networking, disk caching, and support for storage devices up to 4 GB. The final version was System 6.0.1, released in 1993.
- GNO/ME: A third-party UNIX-like multitasking kernel that provided preemptive multitasking under the GUI.
- Backward-Compatible 8-bit Operating Systems:
- The IIgs could run all earlier Apple II operating systems with approximately 95% software compatibility:
- Apple DOS 3.2 and 3.3
- ProDOS 8
- Apple Pascal
- CP/M (with appropriate hardware)
- Native 16-bit Operating Systems:
- Programming Languages:
- Built into ROM
- Applesoft BASIC: Built into ROM and available immediately upon startup, even without loading an operating system.
- Machine Language Monitor: Also in ROM, allowing simple assembly language programming.
- Available Development Languages
- Assembly Language: 65816 assembly programming through tools like APW (Apple Programmer’s Workshop), Apple’s command-line development environment similar to Macintosh Programmer’s Workshop.
- Pascal: Supported through Apple Pascal operating system.
- C: Available through APW and other development tools.
- BASIC variants: Including Integer BASIC and Applesoft BASIC.
- FORTRAN: Available through third-party compilers.
- Logo: Educational programming language support.
- COBOL: Through third-party implementations.
- The IIgs’s 65C816 processor could switch between 8-bit mode (for backward compatibility with 6502 code) and 16-bit mode, allowing it to run software written in either architecture.
- Built into ROM
Notables
- First Apple computer with a color GUI, predating the Macintosh II by six months
- First Apple computer with Apple Desktop Bus (ADB), which became standard across all Apple computers for over a decade
- State-of-the-art Ensoniq audio chip produced the best sound of any personal computer in its era, with capabilities exceeding contemporary Macs
- The “GS” officially stood for “Graphics and Sound”, highlighting its enhanced multimedia capabilities as its defining features.
- Last computer in the original Apple II line designed by Steve Wozniak. “Woz” Limited Edition: The first 50,000 units featured Steve Wozniak’s signature printed on the front case with “Limited Edition” printed below. Buyers received a certificate of authenticity signed by Wozniak and 12 key Apple engineers, plus a personal letter from Woz himself. These limited editions are highly collectible today.
Donated by: Dr. Arlen Michaels
