OAM layout

OAM is a total of 544 bytes in size, consisting of a 512 byte low table and a 32 byte high table. It holds the properties of up all 128 sprites.

Each of these cells represents one byte. The high table packs information on 4 sprites into each byte.

--+--+--+--++ L | Sprite #0       | Sprite #0        | Sprite #0        | Sprite #0                                      | O | x pos (low bits) | y pos           | tile (low bits)  | flip v/h, priority, palette, high bit of tile) | W +--+--+--++  | Sprite #1        | Sprite #1        | Sprite #1        | Sprite #1                                      | T | x pos (low bits) | y pos            | tile (low bits)  | flip v/h, priority, palette, high bit of tile) | A +--+--+--++ B | Sprite #2       | Sprite #2        | Sprite #2        | Sprite #2                                      | L | x pos (low bits) | y pos           | tile (low bits)  | flip v/h, priority, palette, high bit of tile) | E +--+--+--++  |                  |                  |                  |                                                |  |       ....       |    ...           |      ...         |                      ...                       |  |                  |                  |                  |                                                |  +--+--+--++  | Sprite #127      | Sprite #127      | Sprite #127      | Sprite #127                                    |  | x pos (low bits) | y pos            | tile (low bits)  | flip v/h, priority, palette, high bit of tile) | --+--+--+--++ H | Sprites #0-3    | Sprites #4-7     | Sprites #8-11    | Sprites #12-15                                 | I |                 |                  |                  |                                                | G |                 |                  |                  |                                                | H | size select bits | size select bits | size select bits | size select bits                              | | |  |  |  |      |  |  |  |  |      |  |  |  |  |      |  |  |  |  |                                    |  |  v  v  v  v      |  v  v  v  v      |  v  v  v  v      |  v  v  v  v                                    | T | +--+--+--+--+   | +--+--+--+--+    | +--+--+--+--+    | +--+--+--+--+                                  | A | |s |s |s |s |   | |s |s |s |s |    | |s |s |s |s |    | |s |s |s |s |                                  | B | |#4|#3|#2|#1|   | |#4|#3|#2|#1|    | |#4|#3|#2|#1|    | |#4|#3|#2|#1|                                  | L | | x| x| x| x|   | | x| x| x| x|    | | x| x| x| x|    | | x| x| x| x|                                  | E | +--+--+--+--+   | +--+--+--+--+    | +--+--+--+--+    | +--+--+--+--+                                  | |  ^  ^  ^  ^     |   ^  ^  ^  ^     |   ^  ^  ^  ^     |   ^  ^  ^  ^                                   |  |   |  |  |  |     |   |  |  |  |     |   |  |  |  |     |   |  |  |  |                                   |  |   hi x bits      |   hi x bits      |   hi x bits      |   hi x bits                                    | +--+--+--++ |                  |                  |                  |                                                |  |       ....       |    ...           |      ...         |                      ...                       |  |                  |                  |                  |                                                |  +--+--+--++  | Sprites #112-115 | Sprites #116-119 | Sprites #120-123 | Sprites #124-127                               | |                 |                  |                  |                                                |  |                  |                  |                  |                                                |  | size select bits | size select bits | size select bits | size select bits                               | | |  |  |  |      |  |  |  |  |      |  |  |  |  |      |  |  |  |  |                                    |  |  v  v  v  v      |  v  v  v  v      |  v  v  v  v      |  v  v  v  v                                    | | +--+--+--+--+   | +--+--+--+--+    | +--+--+--+--+    | +--+--+--+--+                                  |  | |s |s |s |s |    | |s |s |s |s |    | |s |s |s |s |    | |s |s |s |s |                                  | | |#4|#3|#2|#1|   | |#4|#3|#2|#1|    | |#4|#3|#2|#1|    | |#4|#3|#2|#1|                                  |  | | x| x| x| x|    | | x| x| x| x|    | | x| x| x| x|    | | x| x| x| x|                                  | | +--+--+--+--+   | +--+--+--+--+    | +--+--+--+--+    | +--+--+--+--+                                  |  |   ^  ^  ^  ^     |   ^  ^  ^  ^     |   ^  ^  ^  ^     |   ^  ^  ^  ^                                   |  |   |  |  |  |     |   |  |  |  |     |   |  |  |  |     |   |  |  |  |                                   |  |   hi x bits      |   hi x bits      |   hi x bits      |   hi x bits                                    | +--+--+--++