If the calculator doesn't respond to keystrokes, or if it is otherwise behaving unusually, try resetting it. Resetting the calculator halts the current calculation and cancels program entry, digit entry, a running program, a SOLVE calculation, an ∫ FN calculation, a VIEW display, or an INPUT display. Stored data usually remains intact.
To reset the calculator, hold down the 
key and press 
.
key and press . If the calculator cannot be reset, or if it still fails to operate properly, try clearing the memory. If the calculator still does not respond to keystrokes, insert a thin, pointed object, like a paper clip, in the small RESET hole located on the back of the calculator.
The calculator may reset itself if it is dropped, or if power is interrupted.
