HP HP12C hp 12c_user's guide_English_E_HDPMBF12E44.pdf - Page 74

74 Section 5: Additional Operating Features 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 C 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 Suppose you need to subtract $25.83 from $144.25, and you (mistakenly) key in 25.83, press \, then key in 144.25. 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 Display 25.83\144.25 ~ - 144.25 25.83 118.42 Oops! You mistakenly keyed in the second number first. Exchanges the first and second numbers. The first number keyed in is now in the display. The answer is obtained by pressing the operation key. The ~ key is also useful for checking the first number entered to make sure you keyed it in correctly. Before pressing the operation key, however, you should press ~ again to return the second number entered to the display. Regardless of how many times you press ~, the calculator considers the number in the display to be the second number entered. The Key Occasionally you may want to recall to the display the number that was there before an operation was performed. (This is useful for doing arithmetic calculations with constants and for recovering from errors in keying in numbers.) To do so, press gF (last x). File name: hp 12c_user's guide_English_HDPMBF12E44 Printered Date: 2005/7/29 Page: 74 of 209 Dimension: 14.8 cm x 21 cm