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Y Index Register: Difference between revisions
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The [[Y Index Register]] | The [[Y Index Register]] on 65x processors often holds the current index when iterating over things. It can be incremented or decremented by one with [[INY]] or [[DEY]], but there is no instruction to add or subtract more than one. | ||
On the [[S-SMP]] it is always 8 bits wide. On the [[65c816]], it may be 8 or 16 bits wide. | On the [[S-SMP]] it is always 8 bits wide. On the [[65c816]], it may be 8 or 16 bits wide. | ||
Revision as of 08:50, 1 August 2024
The Y Index Register on 65x processors often holds the current index when iterating over things. It can be incremented or decremented by one with INY or DEY, but there is no instruction to add or subtract more than one.
On the S-SMP it is always 8 bits wide. On the 65c816, it may be 8 or 16 bits wide.
Unlike the X index register, there are no instructions to transfer value of the stack pointer to/from Y.
See Also
Reference
- 8.1.3 of page 3-8-4 of Book I of the official Super Nintendo development manual