Enhanced ULA Control Register
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Revision as of 21:48, 22 December 2018 by wiki>Ped7g (Rewording a bit and adding info from web docs.)
| 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 |