Section 10

Program Editing

There are various reasons why you might want to modify a program you have stored in Program memory: to correct a program that turns out to have errors; to insert new instructions such as ? to store intermediate results or u to display intermediate results; or to replace a uinstruction by an tinstruction.

Rather than clearing program memory and keying in the modified program, you can modify the program already stored in the calculator. This is called program editing.

Changing the Instruction in a Program Line

To change a single instruction in program memory:

1.Press fsto set the calculator to Program mode.

2.Use Ç, Ü, or i.to set the calculator to the program line preceding the line containing the instruction to be changed.

3.Key in the new instruction.

For example, to change the instruction stored in program line 005, press gi.004, then key in the new instruction that is to be stored in program line

005.The instruction previously stored in line 005 will be replaced; it is not automatically “bumped” into line 006.

Example: With the last program from the preceding section still stored in the calculator, suppose you wanted to use register R2 for some other purpose, and so you needed to replace the :2 instruction in program line 005 in the RPN program (line 007 in the ALG program) with, say, :6. You could change the instruction in line 005 as follows:

Keystrokes

Display

 

 

 

(RPN mode)

 

 

 

 

 

 

 

fs

 

 

 

Sets calculator to Program mode.

gi.004

004,43,33,007

Sets calculator to program line

 

 

 

 

preceding that containing the

 

 

 

 

instruction to be changed.

:6

005,

45

6

Keys new instruction into program

 

 

 

 

line 005, replacing the :2

 

 

 

 

instruction previously there.

139

File name: hp 12c pt_user's guide_English_HDPMF123E27

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Printed Date: 2005/8/1

Dimension: 14.8 cm x 21 cm