TI-81

The TI -81 is the first graphics-capable calculator manufactured by Texas Instruments. At its launch in 1990, he was particularly intended for use in algebra and calculus classes. With his over the years numerous advanced successor models (TI -82, TI -83, TI- 83 Plus and TI -84 Plus) he has mostly the basic functions and settings as well as the first time introduced 96x64 pixel display together.

Core of the TI- 81 is a Zilog Z80 microprocessor, as used in most graphic calculators from Texas Instruments. While the processor is usually at least 6 MHz and partly is clocked at up to 15 MHz, it is running in the TI -81 with 2 MHz. The TI- 81 has 2.4 KB of RAM.

The user inputs the TI- 81 take place in the so-called ' Equation operating system '. This is comparable to the interfaces of the successor models.

The functionality of this system, the two-dimensional representation of parametric graphs belongs (in addition to two-dimensional standard graphical representations ), trigonometric calculations ( in degrees or RAD ), simple drawing skills, preparation and handling of up to 6x6 large matrices as well as programming in the Texas Instruments own programming TI- BASIC.

As with his successor models, the power supply of the TI -81 by four AAA batteries and a CR1616 or CR1620 lithium battery as a backup battery, programs, and memory content occurs preserved example during battery replacement.

Texas Instruments also sells an emulator software for PC that mimics the TI -81 and its computational functions.