TI-89

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A second generation TI-89
A second generation TI-89 with a different color scheme
A TI-89 Titanium

The TI-89 (or TI89 ) is a graphical calculator from Texas Instruments (TI) . With its LCD , which has a resolution of 160 × 100 pixels , so-called extended flash memory and TI's Advanced Mathematics Software - which enables the TI-89 to be connected to a computer - it is only used by its bigger brothers, the TI -89 Titanium, TI-92 Plus, Voyage 200, and TI-Nspire . Due to the small display size and the high resolution, older users and people with poor eyesight in particular have problems with the legibility of the characters displayed.

The TI-89 has a microprocessor of the type Motorola 68000 , depending on the hardware version of the calculator (HW1, HW2, HW3 and the new TI-89 Titanium HW4) with 10 MHz or 12 MHz clocked is. The TI-89 has 256 KB RAM (188 KB of which are accessible to the user) and 2 MB (or 4 MB for the TI-89 Titanium) of flash memory ; of this, the user can use 639 KB or 2.7 MB. RAM and flash memory are used to store variables , programs , tables, text files , lists, matrices or even games.

properties

The table below shows the technical characteristics of the Ti-89 compared to the TI-92 and Voyage 200 .

TI-92 TI-92 II TI-92 Plus TI-89 TI-89 Titanium Voyage 200
processor MC68000
Clock frequency 10 MHz 12 MHz 10 MHz 12 MHz
RAM , total 128 kB 256 kB
available a 70 kB 136 kB 188 kB
Flash
ROM , 		total 1 MB 2 MB 4 MB
available a - - 702 kB 639 kB 2.7 MB
Screen type monochrome
Screen resolution 240 × 128 pixels 160 × 100 pixels 240 × 128 pixels
Power supply 4 ×  AA batteries 4 ×  micro batteries
1 × CR2032 1 × CR1616
or CR1620 		1 ×  SR44 1 × CR1616
or CR1620
Initial release 1995 1996 1998 1998 2004 2002
a available to the user

Specifications

The TI-89 is practically a TI-92 Plus without QWERTY - keyboard and with a slightly smaller screen. One reason it was added to the range is that although pocket calculators are allowed in standardized tests in the USA, the TI-92 was considered a computer due to the "real" QWERTY keyboard. In addition, the TI-92 was too bulky for many users. The TI-89 is considerably smaller than this. It also has Flash ROM, another feature that the TI-92 Plus had but not the original TI-92. The TI-89 is not approved for the US ACT test , but its use is not prohibited for the SAT (college selection test).

The main advantage of the TI-89 over its smaller siblings (including the TI-83 ) is the built-in computer algebra system (CAS). This allows the calculator to process algebraic equations and solve for unknowns. The use of the command expand () (dissolves brackets and powers) with the function "a * (2 + c)" produces the result "a * c + 2 * a". If "∫ (x + 1, x)" is to be calculated, the TI-89 displays "(x ^ 2) / 2 + x". He can also solve equations ; for example "solve (x = y + 7 and y = x / 3, x, {x, y})" results in "x = 21/2 and y = 7/2". The TI-89 supports PrettyPrint to display real equations.

In addition to displaying functions in two dimensions , the TI-89 can also display three-dimensional and implicit functions graphically. The current operating system (OS) of the TI-89 has the version number 2.09, the development of the operating system of the TI-89 Titanium has reached OS 3.10.

programming

On the TI-89 you can write small programs yourself in the TI-BASIC programming language, which TI has derived from the well-known BASIC programming language. This is mainly useful for smaller math macros . A PC can also be used to write programs in Motorola 68000 assembly language or C , translate them into machine language using TIGCC and load them onto the calculator using TI-Connect (the newer version of the TI GraphLink program ).

Since 1998, thousands of programs have been developed for every application. Some of the areas covered are math , electronics , biology and a number of games. Many of these games are imitations of Tetris , Minesweeper and other classics, but also a ZX Spectrum emulator and a chess program. There is a development environment that runs directly on the calculator. It's called ams-dev and consists of an IDE , side ; an assembler (asm), as ; a C compiler, cc ; and a debugger , ( db92 ).

In 2004, TI released the TI-89 Titanium, a more modern version of the TI-89 that is expected to replace it in the foreseeable future. This has a completely different housing, twice as much flash memory (of which more than three times as much as before is accessible to the user) and an integrated USB port. The new version of the hardware resulted in incompatibilities with some assembler programs. But they are already working on several solutions; most of the TI-89 programs now run perfectly on the new TI-89 Titanium.

By bridging a capacitor, it is possible to double the speed. However, this is not recommended as it could destroy the calculator.

use

The TI-89 is now part of normal teaching in some schools in the Federal Republic of Germany. TI even grants sponsorship to schools that want to use these devices regularly. In some areas, this pocket calculator is already required (for example in some electrical engineering courses). The increasing spread of these (and similar) devices led to the fact that there are now discussion groups in which explicitly they talk about calculation errors in these devices. Teachers who are informed in this way use this information to show their pupils and students that, despite modern technology, it still makes sense to familiarize themselves with the tools of the trade and not blindly trust the technology.

Web links

Commons : TI-89  - collection of pictures, videos and audio files