HP 20B - Manual (Page 13)

Basic Features
13
When an item for which the
=
key is valid displays, the small annunciator (=) is displayed on the top line at the right of the
screen. Do not confuse this small annunciator (=) with the larger annunciator
(=)
found to the right of a variable.
When an item for which the
I
key is valid displays, the INPUT annunciator is displayed on the top line at the right of
the screen.
Editing and Clearing Entries
The On/CE O Key
Pressing
O
one time cancels current number entries, mathematical operations, or a menu selection, in that order.
Pressing
O
repeatedly when performing multiple operations cancels one operation at a time, from the latest to the earliest.
The Reset :x Menu
The Reset menu allows you to reset some, or all, of the menu items, variables, and registers to their default values.
To open the Reset menu, press
:x
. TVM displays on the top line. Press
<
or
>
repeatedly to scroll to a
specific item. To validate a choice and reset the selected items, press
I
. Press
O
to cancel. If you select the
command to reset the cash flow ( Cash Flow ), statistics ( Stats ), or all values ( All ) items, you will be prompted to confirm your
choice. At the Del. All? , Del. Data? , and Del. CF? prompts, press
I
again to confirm the reset, or
O
to cancel.
While working within a specific menu, pressing
:x
takes you directly to the item of the Reset menu that allows you to
reset that specific menu. For example, if you are working in the Bond menu and you wish to reset all your entries in the Bond
menu, with any item of the Bond menu displayed, press
:x
. Bond displays on screen. At this prompt, pressing
I
resets the Bond menu and returns you to the last item you were working with in the Bond menu.
Notes about Special Menus
The Mode, Memory, Math and Reset menus are special menus; if you were working in a menu prior to entering one of these
special menus, pressing
O
to exit them returns you to your previous menu,. This feature allows you to work in two or more
menus simultaneously without having to exit a menu.
Memory and the Memory Menu
The Memory menu contains the following items: memories 1-9 ( Mem 1-9 ) and 0 ( Mem 0 ), Cash Flow , Statistics ( Stats ), and
Memory . To enter the menu, press
:t
. Press
<
or
>
repeatedly to scroll through the items starting with
memory 1 ( Mem 1 ).
When a memory item is displayed, you can enter a new number and modify the value of the memory by pressing
I
.