Even after the failure of the Intellivision's Keyboard Component and Entertainment Computer System add-ons, Mattel Electronics still felt the need to produce a home computer. The result was 1983's Mattel Aquarius, a primitive, short-lived computer system that also served as a game machine.
Comparable to the computing power of a Commodore VIC-20, the Aquarius contained a 3.5Mhz Z80 CPU, 1.7K of available RAM, the ability to display 16 colors, and a one-voice tone generator. Since the system was not capable of customizable graphics, the only visuals available for programmers were 128 ASCII characters and 128 predefined graphic elements such as lines, shapes and stick figures. During the system's short lifespan, only nine game cartridges were released.
The most important peripheral for game players was a unit called the "Mini-Expander," which added hand controllers, two additional sound channels courtesy of the Intellivision's sound chip, and the ability to use a memory expander and a cartridge simultaneously. A 300 baud modem, printer and data cassette unit were also released for the system. ~ Skyler Miller, All Game Guide