Slot Usage
This article describes some technical aspects of slots for custom track distribution maintainers.
Original Mario Kart Wii
The tracks of Mario Kart Wii are internally addressed by slot identifiers beginning with value 0. The game uses integers (at least 31 bit unsigned) to identify a track. But the network protocol is the bottleneck: track identifiers are transmitted as single byte. So there are only 256 slots available if playing online.
| Slots Hex | Slots Dec | N | Usage |
|---|---|---|---|
| 0x00–0x1f | 0–31 | 32 | Original racing tracks (T11–T84) |
| 0x20–0x29 | 32–41 | 10 | Original battle arenas (A11–A25) |
| 0x2a–0x35 | 42–53 | 12 | not used |
| 0x36 | 54 | 1 | Galaxy Colosseum |
| 0x37–0x3a | 55–58 | 4 | Special scenes like Winning run demo |
| 0x3b–0x41 | 59–65 | 7 | not used |
| 0x42 | 66 | 1 | Maybe reserved. |
| 0x43 | 67 | 1 | Online Protocol: No track selected yet |
| 0x44–0xfe | 68–254 | 187 | not used |
| 0xff | 255 | 1 | Online Protocol: Random selected |
There is a total of 206 (12+7+187) free slots in Nintendo mode.
CT-CODE
CT-CODE (or CT-Code; an abbreviation of Custom Track Code) is an extension of Mario Kart Wii. CT-CODE was developed by MrBean35000vr and Chadderz for their CTGP Revolution. The name CT-CODE was created by Wiimm, when he implemented CT-CODE support in his SZS Tools.
The main purpose is to allow more than 32 racing tracks in one distribution. So it uses free slots and misapply some other slots.
| Slots Hex | Slots Dec | N | Usage | |
|---|---|---|---|---|
| 0x00–0x1f | 0–31 | 32 | Original racing tracks (T11–T84) | |
| 0x20–0x41 | 32–65 | 34 | Custom tracks | |
| 0x42 | 66 | 1 | Maybe reserved. | |
| 0x43 | 67 | 1 | Online Protocol: No track selected yet | |
| 0x44–0xfe | 68–254 | 187 | Custom tracks | |
| 0xff | 255 | 1 | Online Protocol: Random selected | |
CT-CODE uses the free slots and overrides arena and special slots to get space for 221 custom tracks in addition to the 32 original racing tracks.
The BMG message id for track names is calculated by: 0x4000 + slot.
LE-CODE
LE-CODE (or LE-Code; an abbreviation of Leseratte Code) is an extension of Mario Kart Wii. LE-CODE was developed by Leseratte. The name LE-CODE was created by Wiimm, when he implemented LE-CODE support in his SZS Tools.
LE-CODE changes not only the behavior of the game, it changes the online protocol too. The most important modification is, that track identifiers are transmitted as 16 bit value (15 bits unsigned). So 32768 different slots (plus 1 for random) can be used — more than enough for custom tracks. If using about 4000 custom tracks, the game runs in other limits like total game size or usability for track selection. Therefor Leseratte and Wiimm decided to limit the number of supported slots to 4096 (0x1000); it's a space decision too. This limit is implemented in the LE-CODE executor as well in Wiimms SZS Tools and mkw-ana.
| Slots Hex | Slots Dec | N | Usage |
|---|---|---|---|
| 0x000–0x01f | 0–31 | 32 | Original racing tracks (T11–T84) |
| 0x020–0x02b | 32–41 | 10 | Original battle arenas (A11–A25) |
| 0x02a–0x035 | 42–53 | 12 | not used |
| 0x036 | 54 | 1 | Galaxy Colosseum |
| 0x037–0x03a | 55–58 | 4 | Special scenes like Winning run demo |
| 0x03b–0x03d | 59–61 | 3 | not used |
| 0x03e–0x041 | 62–65 | 4 | used for special random selections |
| 0x042 | 66 | 1 | Maybe reserved. |
| 0x043 | 67 | 1 | Online Protocol: No track selected yet |
| 0x044–0xfff | 68–4095 | 4028 | Custom tracks |
| 0x1000–0x7fff | 4096–32767 | 28672 | CT usage possible, but excluded for different reasons |
| 0xffff | 65535 | 1 | Online Protocol: Random selected |
The BMG message id for track names is calculated by: 0x7000 + slot.
Slot Comparison
The following table shows all used slots by Nintendo, CT-CODE and LE-CODE. Due to network protocol limits, Nintendo and CT-CODE can only use the first 256 slots, while LE-CODE can use 65536 slots. Anyway, it is limited to 4096 slots plus 1 slot for random selection for different reasons; see section above.
| Slots Hex | Slots Dec | N | LE-CODE | Nintendo Usage | CT-CODE |
|---|---|---|---|---|---|
| 0x00–0x1f | 0–31 | 32 | Original racing tracks (T11–T84) | ||
| 0x20–0x29 | 32–41 | 10 | Battle arenas (A11–A25) | 34 custom tracks | |
| 0x2a–0x35 | 42–53 | 12 | not used | ||
| 0x36 | 54 | 1 | Galaxy Colosseum | ||
| 0x37–0x3a | 55–58 | 4 | Special scenes like Winning run demo | ||
| 0x3b–0x3d | 59–61 | 3 | not used | not used | |
| 0x3e–0x41 | 62–65 | 4 | used for special random selections | ||
| 0x42 | 66 | 1 | Maybe reserved. | ||
| 0x43 | 67 | 1 | Online Protocol: No track selected yet | ||
| 0x44–0xfe | 68–254 | 187 | 4028 custom tracks | not used | 187 custom tracks |
| 0xff | 255 | 1 | Online Protocol: Random selected | ||
| 0x100–0xfff | 256–4095 | 3840 | no online support | ||
| 0x1000–0x7fff | 4096–32767 | 28672 | CT usage possible, but excluded for different reasons | ||
| 0x8000-0xfffe | 32768–65534 | 32767 | no online support | ||
| 0xffff | 65535 | 1 | Online Protocol: Random selected | ||