| Bits | Description |
|---|---|
| 7 | Pattern address offset (add 128 to pattern address) |
| 6:0 | Sprite number 0-127, Pattern number 0-63 Selects which sprite has its attributes connected to the following registers. Effectively performs an out to port 0x303B with the same value |
| 7 | Ignored |
| 6:0 | Sprite number 0-127 Selects which sprite has its attributes connected to the following registers. |
If the sprite number is in lockstep with port 0x303B (nextreg 0x09 bit 4 is set) Otherwise Bit 7 always reads back as zero.