HP 12c Owners Manual

  Section 8: Programming Basics  91 
 
File name: hp 12c_users guide_English_HDPMBF12E44  Page: 91 of 209   
Printered Date: 2005/7/29    Dimension: 14.8 cm x 21 cm 
 
Identifying Instructions in Program Lines 
Each key on the hp 12c keyboard — except for the digit keys 0 through 9 — is 
identified by a two-digit “keycode” that corresponds to the key’s position on the 
keyboard. The first digit in the keycode is the number of the key row, counting 
from row 1 at the top; the second digit is the number of...

92  Section 8: Programming Basics 
 
 
File name: hp 12c_users guide_English_HDPMBF12E44  Page: 92 of 209   
Printered Date: 2005/7/29    Dimension: 14.8 cm x 21 cm 
 
Displaying Program Lines 
Pressing fs
 to set the calculator from Run mode to Program mode displays the 
line number and keycode for the program line to which the calculator is currently 
set. 
Occasionally you’ll want to check several or all of the instructions stored in 
program memory. The hp 12c enables you to review program...

  Section 8: Programming Basics  93 
 
File name: hp 12c_users guide_English_HDPMBF12E44  Page: 93 of 209   
Printered Date: 2005/7/29    Dimension: 14.8 cm x 21 cm 
 
Program line 07 contains the last instruction you keyed into program memory. 
However, if you press Ê
 again, you’ll see that this is not the last line stored in 
program memory: 
Keystrokes Display   
Ê 
08- 43, 33   00 Program line 08 
As you should now be able to tell from the keycodes displayed, the instruction in 
program line 08 is...

94  Section 8: Programming Basics 
 
 
File name: hp 12c_users guide_English_HDPMBF12E44  Page: 94 of 209   
Printered Date: 2005/7/29    Dimension: 14.8 cm x 21 cm 
 
Expanding Program Memory 
If no instructions have been keyed into program memory, if Continuous Memory 
has been reset, or if f
CLEARÎ
 has been pressed (in Program mode), program 
memory consists of 8 program lines, and there are 20 storage registers available 
for storage of data. 
 
As you key in a ninth instruction, storage register R...

  Section 8: Programming Basics  95 
 
File name: hp 12c_users guide_English_HDPMBF12E44  Page: 95 of 209   
Printered Date: 2005/7/29    Dimension: 14.8 cm x 21 cm 
 
Program memory is automatically expanded like this whenever another seven 
instructions have been keyed into program memory — that is, when you key an 
instruction into program line 16, 23, 30 etc. In each case, the additional program 
lines made available are converted, seven lines at a time, from the last available 
data storage register...

96  Section 8: Programming Basics 
 
 
File name: hp 12c_users guide_English_HDPMBF12E44  Page: 96 of 209   
Printered Date: 2005/7/29    Dimension: 14.8 cm x 21 cm 
 
z  With the calculator in Run mode, pressing gi followed by two digit keys 
sets the calculator to the program line specified by the digit keys. Since the 
calculator is not in Program mode, the line number and keycode are not 
displayed. 
The decimal point is not necessary if the calculator is in Run mode, but it is 
necessary if the...

  Section 8: Programming Basics  97 
 
File name: hp 12c_users guide_English_HDPMBF12E44  Page: 97 of 209   
Printered Date: 2005/7/29    Dimension: 14.8 cm x 21 cm 
 
Keystrokes Display  
 
2. Result of executing program line 
02. 
Ç 
03-    5Program line 03: 5. 
 
25. Result of executing program line 
03. 
Ç 
04-    25Program line 04: b
 
 
156.25 Result of executing program line 
04. 
Ç 
05-    30Program line 05: -
 
 
468.75 Result of executing program line 
05. 
Ç 
06-    5Program line 06: 5 
 
5....

98  Section 8: Programming Basics 
 
 
File name: hp 12c_users guide_English_HDPMBF12E44  Page: 98 of 209   
Printered Date: 2005/7/29    Dimension: 14.8 cm x 21 cm 
 
Example:
 Create a program that calculates the entries in the AMOUNT, TAX, 
and TOTAL columns for each item on the jewelry distributor’s invoice shown on the 
next page, and also calculates the total in each of these columns for all items on 
the invoice. Assume the sales tax is 6
3/4%. 
To conserve lines of program memory, instead of...

  Section 8: Programming Basics  99 
 
File name: hp 12c_users guide_English_HDPMBF12E44  Page: 99 of 209   
Printered Date: 2005/7/29    Dimension: 14.8 cm x 21 cm 
 
Pressing the gu
 keys is not necessary when we do the calculations manually, 
since in Run mode the result of every intermediate calculation is displayed 
automatically; but we’ll include u
 instructions in the program so that the 
intermediate results AMOUNT and TAX are automatically displayed when the 
program is executed. 
Keystrokes...

100  Section 8: Programming Basics 
 
 
File name: hp 12c_users guide_English_HDPMBF12E44  Page: 100 of 209   
Printered Date: 2005/7/29    Dimension: 14.8 cm x 21 cm 
 
Keystrokes Display  
gu 
06-  43  31Pauses to display TAX. 
?+2 
07- 44 40   2 
+ 
08-    40 
?+3 
09- 44 40   3 
Now, to run the program: 
Keystrokes   Display   
fs 
950.61 Sets calculator to Run mode. 
fCLEAR² 
0.00 Clears registers R1– R6. 
6.75?0 
 Stores tax rate. 
13\68.5 
68.5 Enters quantity and price of first 
item on invoice....