Register - Scroll
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Scroll registers represent the position of the upper/left corner of the screen within the space of the main name table. Any part of the screen that would pass an edge of the name table wraps back to the opposite side vertically or horizontally.
| Bit | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
|---|---|---|---|---|---|---|---|---|
| Byte 0 | x | x | x | x | x | x | x | x |
| Byte 1 | - | - | - | - | - | - | - | x |
| Byte 2 | y | y | y | y | y | y | y | y |
| Byte 3 | - | - | - | - | - | - | - | y |
Key
- x - The X value. [0-511]
- y - The Y value. [0-511]
| Background | X Scroll Address | Y Scroll Address |
|---|---|---|
| 0 | $0280 - $0281 | $0282 - $0283 |
| 1 | $0284 - $0285 | $0286 - $0287 |
| 2 | $0288 - $0289 | $028A - $028B |
| 3 | $028C - $028D | $028E - $028F |
This register is a part of the Control Page.
