HP 12C Financial calculator - Manual (Page 108)

108 Section 9: Branching and Looping
File name: hp 12c_user's guide_English_HDPMBF12E44 Page: 108 of 209
Printered Date: 2005/7/29 Dimension: 14.8 cm x 21 cm
The program line immediately following that containing the conditional test
instruction can contain any instruction; however, the most commonly used
instruction there is i. If a i instruction follows a conditional test instruction,
program execution branches elsewhere in program memory if the condition is true
and continues with the next line in program memory if the condition is false.
Example: The following program calculates income tax at a rate of 20% on
incomes of $20,000 or less and 25% on incomes of more than $20,000. To
conserve program lines, the program assumes that the test value — 20,000 — has
been stored in register R
0
and the tax rates — 20 and 25 — have been stored in
registers R
1
and R
2
, respectively.
Note: If a program requires that certain numbers be in the X- and
Y-registers when instructions such as o are executed, it is extremely helpful
when writing the program to show the quantities in each register after each
instruction is executed, as in the following diagram.