Chapter
6:
Graphics 221
memory. Since the first row
is
a repeating pattern
of
"01" bit pairs, it
is
displayed as four dots in the character color. The second row, being a
repeated series of "10" pairs,
is
displayed as four dots in the border color,
producing a set
of
eight horizontal stripes.
You can simplify your experimentation by typing the following imme-
diate mode command:
10
POJ(E
646,14
Location
646
contains the value that BASIC puts in color memory for each
character it displays on the screen.
By
changing this value you can put
characters into the work area, and BASIC will leave them in multicolor
mode. This makes any messages displayed by BASIC multicolor too, but
you should have little difficulty recognizing them.
MIxing
Multlcolor
Characters
WIth
Other
Modes
Because multicolor mode
is
turned on
or
off for each character on the
screen, you can put multicolor characters, custom characters, and normal
text on the same screen.
For
example, try putting the three generations
of
stick man characters together on a single display.
This ability gives you a great deal
of
versatility for designing players
and playfields. Multicolor mode can be useful for both players and play-
fields which are relatively static, while high-resolution custom characters
can be used
at
the same time
to
create the more active players, with standard
characters for text display.
ADVANCED
VIC CHIP
TOPICS
In
this section
we
will cover some aspects of the VIC chip that you will
find helpful
as
you develop more sophisticated programs.
If
you find some
of
the information too difficult,
just
skip over it for now.
As
you become
more familiar with the VIC, this section will become easier to understand.
VIC Chip's
Window
Into
Memory
When it comes
to
memory addresses, the VIC chip and the rest
ofthe
computer are quite different. The 6502 microprocessor in the VIC computer
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