Main handling routine for the spinning coins that come out of ? blocks.
$029A4F is a fourth of the rolling coin tilemap. This tile is 16x16.
$029A54 is the properties of the rolling coin flying from question blocks.
$029A6E is three fourths of the tilemap of the rolling coin. These tiles are 8x8, but they're duplicated and placed above each other, making it 8x16.