Atari 800 Basic Reference Manual

SETCOLOR (SE.)
Note: Doing a PRINT after a LOCATE or GET from the screen may cause the
data in the pixel which was examined to be modified. To avoid this problem,
reposition the cursor and put the data that was read, back into the pixel before
doing the PRINT.
Format:
Example:
SETCOLOR aexp1, aexp2, aexp3
100 SETCOLOR 0, 1, 4
This statement is used to choose the particular hue and luminance to be stored
in the specified color register. The parameters of the SETCOLOR statement are
defined below:
aexp1
aexp2
aexp3
= Color register (0-4 depending on graphics mode)
= Color hue number (0-15. See Table 9-3)
Color luminance (must be an even number between 0 and 14; the
higher the number, the brighter the display. 14 is almost pure
white.)
TABLE 9.3-THE ATARI HUE (SETCOLOR COMMAND)
NUMBERS AND COLORS
COLORS
GRAY
LIGHT ORANGE (GOLD)
ORANGE
RED-ORANGE
PINK
PURPLE-BLUE
BLUE
BLUE
LIGHT BLUE
TURQUOISE
GREEN-BLUE
GREEN
YELLOW-GREEN
ORANGE-GREEN
LIGHT ORANGE
SETCOLOR (aexp2) NUMBERS
0
1
2
3
4
6
7
8
9
10
11
12
13
14
15
Note: Colors will vary with type and adjustment of TV or monitor used.
The ATARI display hardware contains five color registers, numbered
from 0 through 4. The Operating System (OS) has five RAM locations (COLORO
through COLOR4, see Appendix I - Memory Locations) where it keeps track of
the current colors. The SETCOLOR statement is used to change the values in
these RAM locations. (The OS transfers these values to the hardware registers
every television frame.) The SETCOLOR statement requires a value from 0 to 4
to specify a color register. The COLOR statement uses different numbers
because it specifies data which only indirectly corresponds to a color register.
This can be confusing, so careful experimentation and study of the various
tables in this section is advised.
No SETCOLOR commands are needed if the default set of five colors is used.
Although 128 different color-luminance combinations are possible, not more
than five can be displayed at any one time. The purpose of the color registers
and SETCOLOR statement is to specify these five colors.
50 Graphic Modes and Commands

Atari 800 Specifications

General

Brand	Atari
Model	800
Category	Desktop
Language	English