Difference between revisions of "Palette Value Register"
From SpecNext official Wiki
(Rewording a bit and adding info from web docs.) |
(Fixing read/write vs index auto increment description, thanks to Garry help on Facebook to identify the mistake) |
||
| Line 10: | Line 10: | ||
After the write, the palette index is auto-incremented to the next index, if the auto-increment is enabled at {{NextRegNo|$43}}. | After the write, the palette index is auto-incremented to the next index, if the auto-increment is enabled at {{NextRegNo|$43}}. | ||
| + | |||
| + | Read does not auto-increment the index, and reads always the top 8 bits of colour from palette, to read the 9th bit of colour, use {{NextRegNo|$44}} in tandem with value from this register. | ||
The modified palette remains until a Hard Reset. | The modified palette remains until a Hard Reset. | ||
Revision as of 23:31, 6 January 2019
| Number | $41 |
|---|---|
| Readable | Yes |
| Writable | Yes |
| Short Description | Use to set/read 8-bit colours of the ULANext palette. |
Bits 7-0 = Eight bit colour for the palette index selected by the Palette Index Register ($40).
Format is RRRGGGBB - Note the lowest blue bit of colour (ninth bit) will be set to an OR between bit 1 and bit 0.
After the write, the palette index is auto-incremented to the next index, if the auto-increment is enabled at Enhanced ULA Control Register ($43).
Read does not auto-increment the index, and reads always the top 8 bits of colour from palette, to read the 9th bit of colour, use Enhanced ULA Palette Extension ($44) in tandem with value from this register.
The modified palette remains until a Hard Reset.