Commodore 64 User Manual page 71

On page 60 we showed just four locations, two of which control the
screen and background colors. Try typing this:
POKE 53281,7
The background color of the screen will change to yellow because we
placed the value '7'-for yellow-in the location that controls the
background color of the screen.
Try POKEing different values into the background color location, and
see what results you get. You can POKE any value between 0 and 255,
but only 0 through 15 will work.
The actual values to POKE for each color are:
0 BLACK
8 ORANGE
1 WHITE 9 BROWN
2 RED
10
Light RED
3 CYAN 11 GRAY 1
4 PURPLE 12 GRAY 2
5 GREEN 13 Light GREEN
6 BLUE 14 Light BLUE
7
YELLOW
15
GRAY 3
Can you think of a way to display the various background and border
combinations? The following may be of some help:
10 FOR 88 = 0 TO 15
20 FOR BO = 0 TO 15
30 POKE 53280, BR.
40 POKE 53281, BO
50 FOR X = 1 TO 2000 NE:<T X
60 NEXT 8 0 : NEXT 88
RUN
Two simple loops were set up to POKE various values to change the
background and border colors. The DELAY loop in line 50 just slows
things down a bit.
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