TI-80 is a graphing calculator made by Texas Instruments. It was originally designed in 1995 to be used at a middle school level (grades 6-9).
The TI-80 featured the smallest screen and slowest processor (980 kHz proprietary) of any TI graphing calculator. In comparison, the TI-81, released in 1990, featured a 2 MHz Zilog Z80 processor. However, the TI-80 did feature 7 KB of RAM (compared with the TI-81's 2.4 KB). The TI-80 also had more built-in functions than the TI-81 (such as list and table functions, as well as fraction and decimal conversions). Like the TI-81, the TI-80 did not feature a link port. The TI-80 was also the only graphing calculator to use 2 CR2032 lithium batteries (instead of the standard 4 AAA batteries with a lithium backup battery).
Since its release, it has been superseded by the superior TI-73 and TI-73 Explorer. The TI-80 has been discontinued." (Wikipedia)
Download Texas Instruments TI-80 - Various (TOSEC-v2006-04-21):
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