TI-81

Infobox calculator
name = TI-81

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width = 225px
caption =
type = Graphing calculator
manufacturer = Texas Instruments
introduced = 1990
discontinued =
processor = 2 MHz Zilog Z80
memory = 2400 bytes of RAM
display = 96×64 pixels,
16×8 characters
precision =
link =
prog_lang =
power = 4 AAA's,
1 CR1616 or CR1620The TI-81 is the oldest graphing calculator made by Texas Instruments. It was designed in 1990 for use in algebra and precalculus courses. Since its original release, it has been superseded several times by newer calculators - the TI-82, the TI-83, the TI-83 Plus,TI-83 Plus Silver Edition, the TI-84 Plus, and most recently the TI-84 Plus Silver Edition; most of these share the original feature set and 96x64 pixel display that began with this calculator.

Features of the TI-81

The TI-81 is powered by a Zilog Z80 microprocessor, like those used in almost every other Texas Instruments graphing calculator (except the TI-80, TI-89, TI-89 Titanium, TI-92, TI-92 Plus, and Voyage 200). However, the processor runs at only 2 MHz whereas the other Z80-powered Texas Instruments calculators run at a speed of at least 6 MHz (the TI-83 Plus Silver Edition, TI-84 Plus, and TI-84 Plus Silver Edition run at 15 MHz). It contained 2.4 KB of RAM.

The TI-81’s user interactions are provided by its so-called Equation Operation System. This is comparable to the interface provided by the more recent TI-82, TI-83, and so on. This system is capable of such tasks as two-dimensional parametric graphing (in addition to standard two-dimensional function graphing), trigonometric calculations in units of either degrees or radians, simple drawing capabilities, creation and manipulation of matrices up to 6x6 in size, and programming in Texas Instruments’ native TI-BASIC programming language.

As with its successors, the TI-81 is powered by four AAA batteries and one CR1616 or CR1620 lithium backup battery (to ensure programs are kept when the AAA batteries are being changed).

Texas Instruments distributes software which emulates the TI-81 and its Equation Operating System on a desktop computer.

ee also

* Comparison of Texas Instruments Graphing Calculators

External links

* [http://www.ticalc.org ticalc.org] – The largest archive of TI programs available.