DATAMATH CALCULATOR MUSEUM

Texas Instruments TI-81

Date of introduction:	1990	Display technology:	LCD dot matrix
New price:	$110	Display size:	8 * 16 characters
Size:	6.8" x 3.1" x 0.85"
Weight:	5.8 ounces	Serial No:	1174714
Batteries:	4*AAA + CR1620	Date of manufacture:	mth 11 year 1992
AC-Adapter:		Origin of manufacture:	Taiwan
Precision:	13	Integrated circuits:	CPU: Toshiba T6A43 ROM: LH5359©91 RAM: LH5160 Display: 2*T6A39, T6A40
Memories:	0-27
Program steps:	2400 Bytes	Courtesy of:	Joerg Woerner

With the famous TI-81 Texas Instruments entered the market of Graphing calculators. Instead of the traditional 1-line display this kind of calculator offers a dot matrix display with 64 * 96 addressable pixels. In the normal calculator mode up to 8 lines of text information are shown. The TI-81 traces back to the Casio fx-7000G, the world's first Graphing calculator.

The main features of the TI-81 in a short addition:

	Graphing of up to 4 functions at one time.
	Parametric graphing to analyze up to three parametric equations.
	Manipulation of three matrices with dimensions of 6*6.
	One- and two-variable statistical analyses with up to 150 data points.
	Up to 37 programs with a total of 2400 bytes.

From a technical aspect the TI-81 combines the 8-bit hardware architecture known from the Financial Investment Analyst FIA-10 and the enhanced capabilities from the TI-95 Procalc.

The hardware of the TI-81 is similar to a lot of other products: A 8-bit microprocessor of the Z80 family, a huge ROM of 128k Byte capacity, a RAM of 8k Byte size and a driver for the LCD display. You'll find similar architectures with just another balance of RAM and ROM capacity:

Product	ROM-size	RAM-size	Example
Spell-Checker	128k Byte	2k Byte	RR-1
Data Bank	64k Byte	64k Byte	PS-6700
Graphing calculator	128k Byte	8k Byte	TI-81
Modern graphing calc	512k Byte	32k Byte	TI-83 Plus

The TI-81 got soon a slightly modified appearance, search the position of the TI-logo here. Later it was replaced with the enhanced TI-82 and the low-cost TI-80.

The TI-81 was mentioned in TI's press release dated August 15, 2002 to celebrate the 35th anniversary of its invention of the electronic calculator.

Take a short trip to the TI-78, TI-88 and the Hewlett-Packard HP-41C!

The market of graphing calculators was immediately dominated by Texas Instruments and from time to time we get some figures of the accumulated shipment since the introduction of the TI-81. We noted:

Date of press release	Accummulated shipment
Sept. 6, 2000	20,000,000
July 22, 2003	25,000,000

ROM-Versions:

1.1
2.0

You can check the ROM version of your TI-81 using the following key sequence and reading the number on your screen:

[TEST] [ALPHA] [S]

Information provided by ticalc.org.

Exam acceptance:

The TI-81 is permitted (as of September 27, 2007) for use on SAT, ACT, PSAT and AP exams but is not recommended for the AP exam.

Find here the original press release dated September 6, 2000:

Texas Instruments celebrates shipping more than 20 million graphing calculators

DALLAS, September 6, 2000

Texas Instruments, leaders in classroom technology, announced today that they have shipped more than 20 million graphing calculators with this Back-to-School season. Since entering the graphing calculator market in 1990, TI has consistently led the graphing calculator segment and experienced firsthand, the growing trend of classroom technology.

While computers are increasingly used in schools, graphing calculators are the most pervasive form of technology in student's hands across the United States . Graphing calculator sales have been averaging about 10 percent growth for the last several years and are rapidly gaining favor in other countries.

"We're constantly hearing people tell us that they used our products in high school." said Tom Ferrio, vice president, Texas Instruments, "They're always amazed at the power and capabilities that the tools now have."

Graphing technology has changed dramatically since TI first introduced the TI-81 in 1990. Products now boast operating systems that can be electronically upgraded via the Internet, calculator software applications (Apps) for adding specific functionality, and peripherals for data collection and real-world experimentation.

"I've used graphing technology in my classroom for five years," said Melissa Rowe, math teacher, South Grand Prairie High School . "The advancements in the tools have helped my students advance deeper into the math and master more complex subject matter than ever before."

In the last decade, TI has introduced 11 graphing technology products, many of them improved versions of their predecessors. The current product family includes the most popular graphing product in the United States , the TI-83 Plus, for high school and college math and science; the TI-73 for middle grade students; and the TI-89 and TI-92 Plus for advanced mathematics through college and graduate studies.

Over 30 software Apps are available for the above products, with many available to schools and students free. Some Apps even provide actual curriculum in electronic format that compliments classroom textbooks.

To celebrate it's 10th Back-To-School season, TI is offering four TI-83 Plus Apps free with product purchase for a limited time. (More information at www.ti.com/calc).

If you have additions to the above article please email: joerg@datamath.org.