Next comes the X register for sprite 1, the Y register for sprite 1, and so on. After all 16 X and Y registers comes the most significant bit in the X position (X MSB) located in its own register.
The chart below lists the locations of each sprite position register. You use the locations at their appropriate time through POKE statements:
LOCATION | DESCRIPTION | |
---|---|---|
DECIMAL | HEX | |
53248 | ($D000) | SPRITE 0 X POSITION REGISTER |
53249 | ($D001) | SPRITE 0 Y POSITION REGISTER |
53250 | ($D002) | SPRITE 1 X POSITION REGISTER |
53251 | ($D003) | SPRITE 1 Y POSITION REGISTER |
53252 | ($D004) | SPRITE 2 X POSITION REGISTER |
53253 | ($D005) | SPRITE 2 Y POSITION REGISTER |
53254 | ($D006) | SPRITE 3 X POSITION REGISTER |
53255 | ($D007) | SPRITE 3 Y POSITION REGISTER |
53256 | ($D008) | SPRITE 4 X POSITION REGISTER |
53257 | ($D009) | SPRITE 4 Y POSITION REGISTER |
53258 | ($D00A) | SPRITE 5 X POSITION REGISTER |
53259 | ($D00B) | SPRITE 5 Y POSITION REGISTER |
53260 | ($D00C) | SPRITE 6 X POSITION REGISTER |
53261 | ($D00D) | SPRITE 6 Y POSITION REGISTER |
53262 | ($D00E) | SPRITE 7 X POSITION REGISTER |
53263 | ($D00F) | SPRITE 7 Y POSITION REGISTER |
53264 | ($D010) | SPRITE X MSB REGISTER |
The position of a sprite is calculated from the TOP LEFT corner of the 24 dot by 21 dot area that your sprite can be designed in. It does NOT matter how many or how few dots you use to make up a sprite. Even if only one dot is used as a sprite, and you happen to want it in the middle of the screen, you must still calculate the exact positioning by starting at the top left corner location.
Setting up positions in the horizontal direction is a little more difficult than vertical positioning, so we'll discuss vertical (Y) positioning first.
This page has been created by Sami Rautiainen. | |
Read the small print. | Last updated May 12, 2002. |