Apple introduced the Apple IIgs in September 1986. Many at the time considered it to be a replacement for the venerable Apple IIe, but this did not happen.
Apple would go on to keep both computers in production for years to come. The Apple IIgs was officially retired in December 1992, followed shortly by the Apple IIe in early 1993.
The IIgs is a remarkable computer that could have been even better. Apple gave the IIgs a graphical interface, a high-resolution monitor, and enhanced sound capabilities, but the desire to keep the IIgs compatible with the popular Apple IIe resulted in a compromised architecture coupled to the slow 2.8 MHz 65C816 processor.
The original Macintosh, introduced two years earlier in 1984 had an 8 MHz 68000 processor and many IBM-based PCs of the time ran 10 to 12 MHz processors.
However, taken as a whole, the IIgs is great computer residing in a smartly designed case. The IIgs is the best of the Apple II line. The whole system with disk drives and monitor cost $110. Apple originally sold the IIgs for around $999.
Apple IIgs Specs
The IIgs represented a giant leap in the Apple II line. It can still run most earlier Apple II software.
The processor is a 16-bit, 2.8 MHz 65SC816. The processor can be slowed to 1 MHz for compatibility with older Apple II programs, especially games that were designed to run slower.
The Apple IIgs has 1 MB of onboard RAM with and a 2 MB AE GS-RAM card. Earlier versions of the IIgs (ROM 00 and ROM 01) only had 256K onboard RAM. The IIgs is capable of addressing up to 8 MB of RAM.
The user can set up a RAM disk using the GS/OS control panel. My IIgs is currently configured with a 928K RAM disk and 32K RAM cache (see screen shots below).
The IIgs graphics have been significantly enhanced over the IIe. IIgs graphics include a super-hires graphics mode (320 x 200, 16 colors per line colors picked from 4096 colors, or 640 x 200, 16 dithered (4 true) colors per line from 4096 colors).
The IIgs has a large set of commonly used routines called the toolbox in ROM similar to the Mac, and an Ensoniq 5503 Digital Oscillator, a music synthesizer chip capable of wavetable synthesis. The IIgs can use an Apple II composite monitor, a television, or an RGB monitor.
Apple specially developed the AppleColor RGB 12-inch monitor (model A2M6014) to work with the IIgs’ rather unique low horizontal sync rate analog video signal. Third party RGB monitors were also sold.
Ports
Despite having 7 free slots like a IIe plus a RAM card slot (similar to the IIe’s AUX slot), the IIgs also has one serial printer port, one serial modem port, one disk drive port, one ADB port, one composite video port, one joystick (paddle) port, one RGB monitor port, and a headphone jack.
Due to software compatibility reasons, the slots and built in ports are mostly exclusive. Slots 1 and 2 are the modem and printer ports, 3 is the 80-column video, 4 is the ADB mouse, 5 is the 3.5 inch drive support, 6 is the 5.25 inch drive support, and 7 is used for AppleTalk.
The control panel (accessible by pressing Control-Open Apple-Escape) lets you make the decisions as to what mode each slot is in: built-in port or whatever is in the physical slot.
The Apple IIgs does not have an internal hard drive, but Apple and several third party companies sold high-speed SCSI cards for hard drive connectivity.
A few companies like AE sold power supply replacements that contained a hard drive. Some IIgs systems do not have a hard drive.
The IIgs uses ProDOS (8-bit or 16-bit) and GS/OS, a sophisticated operating system with the better features from Mac OS. The IIgs has the ability to use DOS 3.3-based applications on 5.25-inch floppies. DOS 3.3 was designed for 5.25-inch disks with a storage capacity of 143K.
ProDOS can use either 5.25-inch floppy disks or 3.5-inch disks with a storage capacity of 800K to 1.4 MB. The IIgs does not natively support 1.4 MB floppy disks without the additon of a card. My IIgs is running GS/OS 6.0.1.