Section 14: Flags continue227
Keystrokes Display    
5 
    09 5 _    
   
RCL 01 
    10 RCL 01    
   
g SF 25 
    11 SF 25    
   
 ÷  
    12 /    
   
1 
    13 1 _    
   
STO  –  01 
    14 STO – 01    
   
XEQ 
         
   
ALPHA FC?C ALPHA 25 
    15 FC?C 25    
   
g GTO 01 
    16 GTO 01    
   
X Y 
    17 X < > Y    
   
XEQ 
         
   
ALPHA PSE ALPHA 
    18 PSE    
   
g GTO 01 
    19 GTO 01    
   
g GTO · · 
    00 REG 41    
   
Now run the program. Notice how the division by zero never appears.
Keystrokes Display    
PRGM g CLX 
  – 0.0000    
   
XEQ 
         
   
ALPHA ERROR ALPHA 
  – 1.0000    
   
 
  – 1.2500    
   
 
  – 1.6667    
   
 
  – 2.5000    
   
 
  – 5.0000    
   
 
  – 5.0000    
   
 
  – 2.5000    
   
 
  – 1.6667    
   
 
  – 1.2500    
   
 
  – 1.0000    
   
 
  – 5.0000    
  The program halts showing –5.0000.
Audio Enable Flag
Flag 26 is used to control the audible tone in the HP-41C. When flag 26 is set, the HP-41C audible tone will operate. When you clear flag 26, the audible tone will not operate.
You can set, clear and test flag 26, just like any of the general or special purpose flags. But you should remember that this flag also controls the operation of the audible tone. Flag 26 is the only user flag that is automatically set (so that the audible tone functions) each time the HP-41C is turned on.