ZT21000
Expansion unit for ZX81/TS 1000. Promised 64-key auto-repeat big keyboard, 15 colors, 32K RAM onboard, 3 kinds of sound, 33 new BASIC commands, multiple statement and input lines, 6 video pages, high resolution (256×192 pixels) and animation capabilities, user-definable characters and character sets and up to 9 user-definable functions. RS232 and parallel interfaces, two Atari-compatible