HP 12c financial calculator Manuale Utente

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Section 9: Branching and Looping  107 
 
File name: hp 12c_user's guide_English_HDPMBF12E44 
Page: 107 of 209   
Printered Date: 2005/7/29   
Dimension: 14.8 cm x 21 cm 
 
Keystrokes Display   
Ê 
07- 43, 33  02 Line 07: gi02. 
This is the end of the second pass 
through the loop. 
 
–12.23 
 
–530.99 
Portion of third month’s payment 
applied to interest. 
 
–12.36 
Portion of third month’s payment 
applied to principal. 
t(or any key) 
–12.36 
Halts program execution. 
Conditional Branching 
Often there are situations when it is desirable for a program to be able to branch 
to different lines in program memory, depending on certain conditions. For 
example, a program used by an accountant to calculate taxes might need to 
branch to different program lines depending on the tax rate for the particular 
income level. 
The hp 12c provides two conditional test instructions that are used in programs for 
conditional branching: 
z
 
 o tests whether the number in the X-register (represented by the x in the 
key symbol) is less than or equal to the number in the Y-register (represented 
by the y in the key symbol). As discussed in Appendix A, the number in the 
X-register is simply the number that would, if the calculator were in Run mode, 
be currently in the display; and the number in the Y-register is the number 
that would, if the calculator were in Run mode, have been in the display 
when  \ was pressed. For example, pressing 4\5 would place the 
number 4 in the Y-register and the number 5 in the X-register. 
z
 
 m tests whether the number in the X-register is equal to zero. 
The possible results of executing either of these instructions are: 
z
 
 If the condition tested for is true when the instruction is executed, program 
execution continues sequentially with the instruction in the next line of 
program memory. 
z
 
 If the condition tested for is false when the instruction is executed, program 
execution skips the instruction in the next line of program memory and 
continues with the instruction in the following line. 
These rules can be summarized as “DO if TRUE”.