which memory option of PET you are using. It tells you how much
memory space is free for you to use.
4k power-on display
8k power
-
-on display
(A byte is the fundamental data element of the PET computer
and corresponds roughly to one letter or digit of information.
For the curious: the 4k model should show - in theory
-
''4096 bytes" and the 8k, "8192 bytes. "But a few hundred
are used' by the PET internally. The balance shown "3071
and "7167" are net available bytes.)
If you fail to get the power-up display the first time, try turning the
power switch
slowly
off then back on. Rarely will PET fail to respond
to this, but if it does. turn to the
Hints if You Have a
Problem
section
at the back of this pamphlet.
Most noticeable in the display is a flashing white square called a
cursor. Whenever PET is waiting for some keyboard information,
the cursor will begin blinking and this is where the next charac-
ter will appear if it is typed in.
Touring the keyboard
But, before you can speak to your PET, we need to take a brief
tour of the keyboard.
Each key has a thin, transparent plastic film covering the keytop
which should be removed. This protection was left in place to
protect the keys against scratches during shipping. To remove the
film, carefully peel off with your fingernail.
Key top legends bear much resemblance to those of a standard
typewriter keyboard, but there are a few differences.
The letters are all in virtually the same place as on a standard
typewriter keyboard, but, for your convenience in numerical
computations, the numbers are separate and laid out very much
like a calculator keyboard. (See Figure 1.)
Figure 1. The keyboard
On most typewriters, if you strike a letter key, without shifting,
you will get a lower case letter. On your PET, if you press a letter key
without shifting, you will get the capital letter. (See Figure 2.)
Figure 2. The characters without shifting
If, on the other hand, you simultaneously press the shift key and a
letter key, you will get the particular graphic that appears above the
letter: (See Figure 3.)
The graphics characters are a special set of symbols unique to PET.
They are used to draw pictures and lines on the screen and to perform
simple animation. The graphics can be printed on the screen just like
any other letter or digit.
For now, locate the
L
key and press it a number of times to get a
row of characters-AAAAA -on the screen. (Do
riot
use the
2
key. If you did, you'd get
L .)
I
SHIFT
3
