SMW Memory Map
|$7E0036||2 bytes||Misc.||Mode 7 rotation. Its values are calculated and stored into the respective Mode 7 parameter mirrors at $7E:002E through $7E:0035.
Values #$0000 through #$01FF are all different values, after that it's the same pattern - that is, if you add this 16-bit address with #$0200, there is a 360 degree rotation.
Furthermore, this address is used in the brown chained platform code as an index to the sine and cosine tables at $07:F7DB.