Atari XL User Manual

138 The Atari XL Handbook
Points and lines
To light up a point (or pixel) on the screen the
command PLOT is used. The command is followed
by
two numbers - the row and column in which the
point lies.
PLOT 20, 10
lights a pixel on the screen in the colour selected by
the previous CO 1.,0 R command. Try PLOTting a
few
points around the screen. Mode 5 has 80
columns, numbered from 0 to 79, and 40 rows - 0 to
39.
If you use numbers which are too large the XL
will print tERROR - 141'; if you use numbers less
than zero the Atari prints tERROR - 3'.
Try changing the colour of the points you PLOT by
using COLOR 2 or COLOR 3. COLOR 0 will give
invisible points as it selects the background colour.
This means that you can erase pixels by returning
them to the background colour.
When you have finished experimenting with the
PLOT command clear the screen again by typing:
GRAPHICS 5
The command D RA WTO draws lines on the
display. Set a pixel by typing:
COLOR 1
PLOT 5,5
and then try:
DRAWTO 60,5
DRAWTO 60,35
DRAWTO 5,5

Atari XL Specifications

General

Brand	Atari
Model	XL
Category	Desktop
Language	English