90 Section 5: Additional Operating FeaturesSpecial Displays

Running. Certain functions and many programs may take several seconds or more to produce an answer. During these calculations, the word running flashes in the display to let you know that the calculator is running.

Overflow and Underflow. If a calculation results in a number whose magnitude is greater than 9.999999999 ×1099, the calculation is halted and the calculator displays 9.999999 99 (if the number is positive) or –9.999999 99 (if the number is negative).

If a calculation results in a number whose magnitude is less than 10–99, the calculation is not halted, but the value 0 is used for that number in subsequent calculations.

Errors. If you attempt an improper operation — such as division by zero — the calculator will display the word Error followed by a digit (0 through 9). To clear the Error display, press any key. This does not execute that key’s function, but does restore the calculator to its condition before the improper operation was attempted. Refer to Appendix D for a list of error conditions.

Pr Error. If power to the calculator is interrupted, the calculator will display Pr Error when next turned on. This indicates that Continuous Memory — which contains all data, program, and status information — has been reset.

The Key in RPN Mode

Suppose you need to subtract $25.83 from $144.25, and you (mistakenly) key in

25.83as the first number and then key in 144.25 as the second number. But then you realize that when written down on paper, the desired calculation reads

144.25– 25.83, so that you have unfortunately keyed in the second number first.

To correct this mistake, merely exchange the first and second numbers by pressing ~, the exchange key.

Keystrokes (RPN mode)

25.83\144.25

~

-

Display

144.25Oops! You mistakenly keyed in the second number first.

25.83Exchanges the first and second numbers. The first number keyed in is now in the display.

118.42The answer is obtained by pressing the operation key.

File name: hp 12c pt_user's guide_English_HDPMF123E27

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Printed Date: 2005/8/1

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