You can cycle colors 1,2,3 in every palette (like, 2 goes to 1, 3 to 2, 1 to 3) - this keeps the background color the same and uses the same predefined set of colors. You can cycle all four colors (1 to 0, 2 to 1, 3 to 2, 0 to 3), this will change the background color too, but don't forget that it is shared between all palettes, so only last write to any color 0 will take effects - thus the background will always have one of colors of one of palettes.

You can also cycle colors between palettes, cycle the 4-color sub palettes itself (all colors of palette 1 to palette 0 etc).

You can even cycle color values. Notice that low nibble of a hex code for a color is hue (0-d), and high nibble is brightness (0-3). So you can keep the top nibble while incrementing or decrementing low nibble, and have effect similar to the one that you can see while moving the Hue slider in a graphics editor.

Im very very new to the whole nes grafx thing but I have a bit of a problem wrapping my head around the pallets. I am using Shiru's nes screen tool which has the "nes pallet" of the 53ish colors and 4 "sub pallets" of the background colors plus 3 each for 15 colors. Could I confirm these AREN'T related to which colors cycle?

In this bit of code

I pick my cycling colors right? So I don't understand where my 4 extra colors are coming from if nametables only have 15 colors? Did I get mixed up here?

Thanks!

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