Section 1: Getting Started18
Keystrokes Display    
10  10 _    
1/x   1 / X
 0.1000 		  Press and hold 1/x for a moment, then release it. Notice tat the function name remains in the display while you hold the key down, and the function is executed when you release it.
Now nullify a function by holding it down for more than about half a second.
Keystrokes Display    
10  10 _    
1/x   1 / X
 NULL 		  Press and hold 1/x until the name disappears from the display and NULL appears. When you release the key, the function is not executed.
   10.0000   Previous contents of the display are returned to the display.
g CLX   0.0000   Clears the display.
The ALPHA Keyboard
When you place the HP-41C into ALPHA mode ( ALPHA ), a special alphanumeric keyboard becomes active. The characters printed in blue on the lower face of each key are what you get when you press a key. The functions printed on the face and above the keys are no longer active. In addition, an ALPHA character (not printed on the key) becomes available as a shifted key. So when the HP-41C is in ALPHA mode...
  yx  
1 ⁄ x
B
  ...the function printed above the key is not longer active...
  ...and the function printed on the face of the key is no longer active. A shifted ALPHA character is now associated with the face of each key (but not printed on it). To select the character associated with this key, press g and the key (the shifted character on the illustrated key is lower case b). These shifted characters are shown on page 19.
  The primary function of each key is now the ALPHA mode character printed in blue on the lower face of each key. To select this character, simply press the key.