Enhanced ULA Control Register

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Number $43
Readable Yes
Writable Yes
Short Description Enables or disables Enhanced ULA 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 Enabe ULANext mode if 1. (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
%011 Tilemap first palette
%111 Tilemap second palette