For Sale- Tested and working graphing calculator in good condition.
Works 100%, no problems. LCD screen has no bad pixels and is easy to read. All buttons and features tested and working.
I picked up about a dozen used TI graphing calculators to resell- all have been carefully cleaned and tested. Most show a little bit of wear from normal use, a couple are in mint or near mint shape. Please look at the photos carefully- the photos are of the actual calculator being sold. Also have TI-83 Plus, TI-84, TI-89 Titanium, and some others as well.
The following info thanks to Wikipedia.org:
The TI-81 is the first 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 Since its original release, it has been superseded several times by newer calculators - the TI-82, the TI-83, the TI-83 Plus, TI-83 Plus Silver Edition, the TI-84 Plus, the TI-84 Plus Silver Edition, and most recently the TI-Nspire and TI-Nspire CAS; 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-81Â’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 InstrumentsÂ’ native TI-BASIC programming language.
In early 2010, an exploit was found that can be used to execute machine code on the TI-81, which is impressive as the calculator had no link port. Programs can be written and assembled using a toolset called Unity, which will output the machine code that the user must manually input on the calculator.
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.
Send your zip code for ship cost- should be between $3.95 and $5.95 if you are in the continental USA (Nov. 2012).
