TI -86 用户手册

下载
页码 431
18
Chapter 1:  Operating the TI
-86
01OPER.DOC   TI-86, Chap 1, US English   Bob Fedorisko   Revised: 02/13/01 2:18 PM   Printed: 02/13/01 2:59 PM   Page 18 of 22
01OPER.DOC   TI-86, Chap 1, US English   Bob Fedorisko   Revised: 02/13/01 2:18 PM   Printed: 02/13/01 2:59 PM   Page 18 of 22
You can adjust the display contrast anytime to suit your viewing angle and lighting
conditions. As you adjust, a number from 
0
 (lightest) to 
9
 (darkest) in the top-right corner
indicates the current contrast setting. The number is not visible when the contrast is
extremely light or dark.
As the batteries weaken over time, the actual contrast level of each number shifts. For
example, say you set the contrast to 
3
 with fresh batteries. As the batteries weaken, you will
need to set the contrast to 
4
, then 
5
, then 
6
, and so on, to retain the original contrast level.
However, you need not replace the batteries until the low-battery message is displayed.
The Home Screen
When you first turn on your TI
-86, the home screen is displayed. Initially, the home screen
is a blank screen, except for the entry cursor ( Å ) in the top-left corner. If you do not see
the cursor, press -, and then press and hold # or $ to adjust the contrast (page 17).
On the home screen, you can enter and evaluate expressions, and view the results. You also
can execute instructions, store and recall variable values, and set up graphs and editors.
To return to the home screen from any other screen, press - l.
Displaying Entries and Answers
The home screen displays up to eight lines with a maximum of 21 characters per line. If an
expression or series of instructions exceeds 21 characters and spaces, it automatically
continues on the next line.
After all eight lines are full, text scrolls off the top of the display. You can press $ to scroll
up the home screen, only as far as the first character in the current entry. To retrieve, edit,
and re-execute previous entries, use - ¢ (page 28).
The TI
-
86 has 40 contrast
settings, so each number
0
 through 
9
 represents four
settings.
You need not clear the home
screen to begin a new entry.