Palette Value Register

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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). And also the index of Enhanced ULA Palette Extension ($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 Enhanced ULA Palette Extension ($44) in tandem with value from this register.

The modified palette remains until a Hard Reset.