Sprite Attribute 0 (with INC) Register: Difference between revisions
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core 2.00.23 changes |
m Xalior moved page Sprite port-mirror Attribute 0 (with INC) Register to Sprite Attribute 0 (with INC) Register: match formal nextreg.txt name |
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Eight low bits of X position. MSB of X-pos is in "byte 3". | Eight low bits of X position. MSB of X-pos is in "byte 3". | ||
After write into sprite-attribute "byte 1" ({{PortNo|$xx57}}), the {{NextRegNo|$34}} is incremented (with all consequences stemming from such action). If the sprite | After write into sprite-attribute "byte 1" ({{PortNo|$xx57}}), the {{NextRegNo|$34}} is incremented (with all consequences stemming from such action). If the sprite 127 was modified, the result of the increment is officially "undefined behaviour", and code should explicitly set valid 0..127 sprite index before next sprite-attribute manipulation. | ||
Latest revision as of 12:18, 14 October 2025
| Next Register Number | $75 |
|---|---|
| Readable | No |
| Writable | Yes |
| Short Description | Same as NextReg:$35 (write first byte of sprite-attributes), plus increments NextReg:$34 |
Eight low bits of X position. MSB of X-pos is in "byte 3".
After write into sprite-attribute "byte 1" ( IO:$xx57), the NextReg:$34 is incremented (with all consequences stemming from such action). If the sprite 127 was modified, the result of the increment is officially "undefined behaviour", and code should explicitly set valid 0..127 sprite index before next sprite-attribute manipulation.