TI-89
The TI-89 (or TI89) is a graphing calculator developed by Texas Instruments (TI). Possessing a 160×120 pixel resolution LCD screen with advanced flash memory, coupled with TI's Advanced Mathematics Software, the TI-89 is dwarfed only by its larger and slightly more powerful cousin, the Voyage 200.
The heart of the TI-89 is the Motorola 68000 microprocessor, which, depending on the calculator's hardware version, runs at 10 MHz or 12 MHz. Texas Instruments has allocated 256 KB of the total RAM for the unit (190 KB of which are available to the user) and 2 MB of flash memory (700 KB of which is available to the user). The RAM and Flash ROM are used to store variables, programss, tables, text files, and lists.
The TI-89 is essentially a TI-92 Plus with a limited keyboard and smaller screen. It 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, some people found the TI-92 unwieldy and overly large. The TI-89 is significantly smaller. It has a flash ROM, a feature present on the TI-92 Plus but not on the original TI-92. The TI-89 is not permitted on the ACT, although it is permitted on the SAT examinations.
The major advantage of the TI-89 over lower-model TI calculators is its built-in Computer Algebra System, or CAS. The calculator can evaluate most algebraic expressions and solve for the unknowns. For example, if asked to expand the expression "a*(2+c)" it returns "a*c+2*a". If it is asked to evaluate "∫(x+1,x)", it returns "(x^2)/2 + x". It can also solve systems of equations; for example, "solve(x=y+7 and y=x/3,x,{x,y})" gives "x=21/2 and y=7/2". The TI-89 pretty prints algebraic expressions — that is, it represents expressions as they would be written on paper, not as they would be entered into a computer: "(x+y)/(7^a)" becomes
In addition to the standard two-dimensional function plots, it can also produce three-dimensional graphs and implicit plots.
The TI-89 is directly programmable in a language called TI-BASIC, TI's derivative of BASIC for calculator applications. Using a PC, one can also develop one's own programs in Motorola 68000 assembly language or 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. Many available games are generic clones of Tetris, Minesweeper, and other classic games, 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).
After the summer of 2004, the TI-89 will be replaced by the TI-89 Titanium, an upgraded version with a completely different case design, three times the memory of the original TI-89, and an integrated USB port. Unfortunately, this may cause some compatibility issues with C and assembly programs developed for the original TI-89. They will have to be recompiled to work on the Titanium.
User features
Programming
External links