Difference between revisions of "Enhanced ULA Control Register"
From SpecNext official Wiki
(Rewording a bit and adding info from web docs.) |
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{{NextRegister | {{NextRegister | ||
|Number=$43 | |Number=$43 | ||
| − | |Readable= | + | |Readable=Yes |
|Writable=Yes | |Writable=Yes | ||
|ShortDesc=Enables or disables ULANext interpretation of attribute values and toggles active palette. | |ShortDesc=Enables or disables ULANext interpretation of attribute values and toggles active palette. | ||
}} | }} | ||
| − | |||
{| class="wikitable" | {| class="wikitable" | ||
! Bit !! Function | ! Bit !! Function | ||
|- | |- | ||
| − | | 7 || | + | | 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 || Disable the standard Spectrum flash feature to enable the extra colours. (0 after a reset) | ||
| + | |} | ||
| + | |||
| + | Possible bits 6-4 for palette select (bit 6 selects first/second, 5-4 select type): | ||
| + | {| 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 |
|} | |} | ||
Revision as of 22:48, 22 December 2018
| Number | $43 |
|---|---|
| Readable | Yes |
| Writable | Yes |
| Short Description | Enables or disables ULANext 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 | Disable the standard Spectrum flash feature to enable the extra colours. (0 after a reset) |
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 |