TI-89

The TI-89 (or TI89) is a powerful graphing calculator developed by Texas Instruments. It has a graphics LCD display with a resolution of 160x100 pixels. It has 256 kilobytes of RAM (190 of which are available to the user) and 2MB of flash memory (700KB of which is available to the user). The RAM and Flash ROM are used to store variables, programs, tables or even games. The heart of the TI-89 is the Motorola 68000 microprocessor, which runs at 12MHz.

The TI-89 is fundamentally a TI-92[?] with limited keyboard, and smaller screen. The TI-89 was created partially in response to the fact that while calculators are allowed on many standardized tests, the TI-92 was considered a computer due to the QWERTY layout of its keyboard. Additionally, many disliked the TI-92 for its large size. The TI-89 is significantly smaller.

The biggest advantage of the TI-89 is symbolic manipulation (due to a Computer algebra system), which means that the calculator can compute not only with numbers, but even with symbols. For example, if you enter "a*(2+c)" it returns "2*a+a*c". If you enter "∫(x+1)dx", you get "(x^2)/2 + x".

In addition to the normal two-dimensional plots of functions, it can also produce three-dimensional graphs and implicit plots.

The TI-89 is directly programmable in a language called "Keystroke", vaguely reminiscent of BASIC. Using a PC, you can also develop your own programs in Motorola 68000 assembly language and C, translate them to machine language, and copy them to the calculator.

Since 1998, thousands of programs for math, electronics, biology, or just for fun have been developed. Most available games are the generic clones of Tetris or Minesweeper, but some programs are really amazing — for example, a ZX Spectrum emulator and a chess playing program. There is also an on-calc development environment available. It is called ams-dev[?], and consists of an IDE, side[?]; an assembly language (asm) compiler, as[?]; a C compiler, cc[?]; and a debugger, db92[?]).

External Links

• The biggest collection of programs and other resources is probably ticalc.org (http://www.ticalc.org).
• The aforementioned chess program and many programming utilities are available at the TI Chess Team website (http://tict.ticalc.org/).
• Information and programs for many TI and HP calculators is available at calc.org (http://www.calc.org).
• CalcWare (http://www.calcware.org/) is a programming group that develops for the TI-89.
• More sites can be found at the Open Directory TI-89 category (http://directory.google.com/Top/Computers/Hardware/Calculators/TI_Graphing_Calculators/TI-89/).