Commodore VIC-20 User Manual page 153

APPENDIX 1: SCREEN MEMORY MAPS
Use this appendix to find the memory location of any position on the
screen. Just find the position in the grid and add the numbers on the
row and column together. For example, if you want to poke the
graphic "ball11 character onto the center of the screen, add the
numbers at the edge of row 11 and column 11 (7900+10) for a total of
7910. If you poke the code fora ball (81, see Appendix H) into location
7910 by typing POKE 7910,81, a white bail appears on the screen. To
change the color of the ball (or other character), find the correspond
ing position on the color codes memory map, add the row and column
numbers together (38620 + 10, or 38630) for the color code and type a
second poke statement. For example, if you poke a color code into
this location, POKE 33630,3 the ball will change color to cyan. Note
that when PQKEing, the character color numbers are one less than
the numbers on the color keys—as shown below.
Abbreviated
Code
0
1
2
3
4
5
6
7
List of Color Codes
Color
Black
White
Red
Cyan
Purple
Green
Blue
Yellow
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