Solution 12651: Clearing the Memory on the TI-81.
How is the memory cleared and reset the TI-81?To clear the memory and reset the TI-81, press the [2nd] key and then the [+] key. A screen will be displayed with the options to reset the graphing calculator or return to the home screen. This screen will also show the amount of available memory and how much memory is being used by the STAT editor and the PRGM editor.
If option 2. Reset is selected, the memory of the graphing calculator is erased and all defaults are set to factory defaults. If the screen goes entirely blank after this procedure, adjust the contrast by pressing and releasing the [2nd] key and then holding down the up arrow until the cursor is again visible.