Section 12: Subroutines185
Begin by loading the master program, BTU.
Keystrokes Display    
PRGM 
       
   
g GTO · · 
  00 REG 45    
   
g LBL 
       
   
ALPHA BTU ALPHA 
  01 LBLTBTU    
  The master program name.
XEQ 
       
   
ALPHA TEMP ALPHA 
  02 XEQTTEMP    
  Executes the TEMP program (to be loaded later) as a subroutine.
XEQ 
       
   
ALPHA AREA ALPHA 
  03 XEQTAREA    
  Executes the AREA program (to be loaded later) as a subroutine.
 ×  
  04 *    
   
.47 
  05 .47    
  The convective heat transfer coefficient.  
 ×  
  06 *    
  Computes the final result.
ALPHA 
       
   
LOSS=
  07TLOSS= _    
  The final label.
g ARCL · X 
  08 ARCL X    
  Recalls the answer into the ALPHA register.
g AVIEW ALPHA 
  09 AVIEW    
  Displays the label and answer.
g GTO · · 
  00 REG 40    
   
Now load the TEMP program.
Keystrokes Display    
PRGM 
       
   
g GTO · · 
  00 REG 45    
   
g LBL 
       
   
ALPHA TEMP ALPHA 
  01 LBLTTEMP    
  The program name.
ALPHA HEATER? ALPHA 
  02THEATER?    
   
PROMPT ( Σ+ ) 
  03 PROMPT    
  Prompts and stops for input.
ALPHA AIR ALPHA 
  04LBLTAIR    
   
PROMPT ( Σ+ ) 
  05 PROMPT    
  Prompts and stops for input.
 –  
  06 –    
  Finds difference.
g GTO · · 
  00 REG 36    
   
   Note that the convective heat transfer coefficient is an approximation of the actual coefficient. Care was used to find a valua that resulted in acceptable values for the largest temperature span, cylinder area, cylinder position, and construction. The coefficient actually changes as all of these variables change.