The Letter Keys And Variables - HP -22S Owner's Manual

Canceling Menus. Canceling a menu erases the current menu labels.
There are several ways to cancel menus:
• Menus are automatically canceled when you press a menu key to
execute a function.
• [!] cancels the menu without executing a function. In multi-level
menus, [!] backs up one level at a time.
• @] cancels the menu, regardless of what level it is at.
• Menus replace one another. For example, if you accidently press
. , MODES
I
instead of .,
UNITS
I,
you can press .,
UNITS
I
without first
canceling the MODES menu.
M TMP L
~~~
The Letter Keys and Variables
Most of the keys have a letter A through Z associated with them. Each
letter is the name of a calculator variable. The 26 variables are loca-
tions in calculator memory used to store and retrieve numbers.
Pressing ,
STO
I
(store) or ,
RCL
I
(recall) turns on the
A .. Z
annunciator to
let you know that the keys are using their letter assignments. For ex-
ample, 12 ,
STO
I
turns on the
A .. Z
annunciator. Then, pressing [E]
displays A= 12.0000, indicating that 12 has been stored into variable
A. This series of keystrokes is written as 12 ,
STO
I
A.
Storing and retrieving numbers using variables is covered in more de-
tail in chapter 2. Using variables with'
EVAL
I
and'
SOLVE
I
is covered in
chapter 6.
20 1: Getting Started