Program Editing; Section 10: Program Editing; Changing The Instruction In A Program Line - HP 12C User Manual

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 u instruction by an t instruction.
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 fs to 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 R
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
(RPN mode)
fs
gi.004
:6
File name: hp 12c pt_user's guide_English_HDPMF123E27
Printed Date: 2005/8/1
Section 10

Program Editing

Display
Sets calculator to Program mode.
004,43, 33, 007
Sets calculator to program line
preceding that containing the
instruction to be changed.
005, 45 6
Keys new instruction into program
line 005, replacing the :2
instruction previously there.
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Page: 139 of 275
Dimension: 14.8 cm x 21 cm
for some other purpose, and so
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