ULA Palette Control Register: Difference between revisions
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m Xalior moved page Enhanced ULA Control Register to ULA Palette Control Register: match formal nextreg.txt name |
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{{NextRegister | {{NextRegister | ||
|Number=$43 | |Number=$43 | ||
|Readable= | |Readable=Yes | ||
|Writable=Yes | |Writable=Yes | ||
|ShortDesc=Enables or disables | |ShortDesc=Enables or disables Enhanced ULA interpretation of attribute values and toggles active palette. | ||
}} | }} | ||
{| class="wikitable" | |||
! Bit !! Function | |||
|- | |||
| 7 || 1 to disable palette index write auto-increment | |||
|- | |||
| 6-4 || Select palette for reading or writing | |||
|- | |||
| 3 || Select Sprites palette (0 = first palette, 1 = second palette) | |||
|- | |||
| 2 || Select Layer 2 palette (0 = first palette, 1 = second palette) | |||
|- | |||
| 1 || Select ULA palette (0 = first palette, 1 = second palette) | |||
|- | |||
| 0 || Enable ULANext mode if 1. (0 after a reset) | |||
|} | |||
n.b. Bits 6-4 select palette for reading or writing whereas bits 3-1 select the palette for the display signal generator. | |||
Possible bits 6-4 for palette select (bit 6 selects first/second, 5-4 select type): | |||
{| class="wikitable" | {| class="wikitable" | ||
! | ! Bits 6-4 !! selects | ||
|- | |||
| %000 || ULA first palette | |||
|- | |||
| %100 || ULA second palette | |||
|- | |||
| %001 || Layer 2 first palette | |||
|- | |||
| %101 || Layer 2 second palette | |||
|- | |||
| %010 || Sprites first palette | |||
|- | |- | ||
| | | %110 || Sprites second palette | ||
|- | |- | ||
| | | %011 || Tilemap first palette | ||
|- | |- | ||
| | | %111 || Tilemap second palette | ||
|} | |} | ||
Write will also reset the index of {{NextRegNo|$44}}, so the next write there will be considered as first byte of colour. | |||
Latest revision as of 11:03, 14 October 2025
| Number | TBRegisterNumber::$43 |
|---|---|
| Readable | TBRegisterReadable::Yes |
| Writable | TBRegisterWritable::Yes |
| Short Description | ShortDesc::Enables or disables Enhanced ULA interpretation of attribute values and toggles active palette. |
| Bit | Function |
|---|---|
| 7 | 1 to disable palette index write auto-increment |
| 6-4 | Select palette for reading or writing |
| 3 | Select Sprites palette (0 = first palette, 1 = second palette) |
| 2 | Select Layer 2 palette (0 = first palette, 1 = second palette) |
| 1 | Select ULA palette (0 = first palette, 1 = second palette) |
| 0 | Enable ULANext mode if 1. (0 after a reset) |
n.b. Bits 6-4 select palette for reading or writing whereas bits 3-1 select the palette for the display signal generator.
Possible bits 6-4 for palette select (bit 6 selects first/second, 5-4 select type):
| Bits 6-4 | selects |
|---|---|
| %000 | ULA first palette |
| %100 | ULA second palette |
| %001 | Layer 2 first palette |
| %101 | Layer 2 second palette |
| %010 | Sprites first palette |
| %110 | Sprites second palette |
| %011 | Tilemap first palette |
| %111 | Tilemap second palette |
Write will also reset the index of {{#ask: TBRegisterNumber::$44 }} ($44), so the next write there will be considered as first byte of colour.