Printing The Display; Contrast Control; Clearing Operations; Attention - HP -28S Manual

Printing the Display
To print the current display image:
1. Press and hold
I
ON
I.
2.
Press [JJ (the key with HPRINT" above it).
3.
Release
I
ON
I.
Contrast Control
To change the display contrast:
1. Press and hold
I
ON
I.
2. Press
~
to increase the contrast or press
G
to decrease the con-
trast. As long as you hold down
1
ON
I,
you can press
~
or
G
repeatedly or continuously to find the best contrast.
3. Release
I
ON
I.
Clearing Operations
There are three clearing operations, given below in order of increasing
severity.
Attention
To return to the normal stack display, execute Attention by pressing
ION
I. In
some cases you may need to press
ION
1
twice. Attention has
following effects:
• Clears the command line.
• Cancels all command or procedure execution.
• Exits special operations such as FORM, PLOT, and catalogs.
• Restarts normal keyboard operation.
216 25: System Operations