Palette Value (8 bit colour) Register: Difference between revisions

From SpecNext Wiki
Jump to: navigation, search
Fixing read/write vs index auto increment description, thanks to Garry help on Facebook to identify the mistake
m Xalior moved page Palette Value Register to Palette Value (8 bit colour) Register: match formal nextreg.txt name
 
(2 intermediate revisions by 2 users not shown)
Line 9: Line 9:
Format is RRRGGGBB - Note the lowest blue bit of colour (ninth bit) will be set to an OR between bit 1 and bit 0.
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 {{NextRegNo|$43}}.
After the write, the palette index is auto-incremented to the next index, if the auto-increment is enabled at {{NextRegNo|$43}}. And also the index of {{NextRegNo|$44}} is reset, so the next write there will be considered as first byte of colour.


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.
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.

Latest revision as of 10:57, 14 October 2025

Number TBRegisterNumber::$41
Readable TBRegisterReadable::Yes
Writable TBRegisterWritable::Yes
Short Description ShortDesc::Use to set/read 8-bit colours of the ULANext palette.

Bits 7-0 = Eight bit colour for the palette index selected by the {{#ask: TBRegisterNumber::$40 }} ($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 {{#ask: TBRegisterNumber::$43 }} ($43). And also the index of {{#ask: TBRegisterNumber::$44 }} ($44) is reset, so the next write there will be considered as first byte of colour.

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 {{#ask: TBRegisterNumber::$44 }} ($44) in tandem with value from this register.

The modified palette remains until a Hard Reset.