@ZapJackson:
You can get all possible RGB combinations assigned to any of the 16 available attributes of screen 0 using
_PALETTECOLOR. This way you can use the _RGB32 function as in:
PRINT "This is printed in color 9, which maps to bright blue in the default VGA palette;" PRINT "But now color 9 is Goldenrod."
But you'll still be limited to 16 attributes, 0 to 15. If you want to use *any* color in the 32bit color space, you can switch to graphics mode using _NEWIMAGE. The snippet below creates an 800x600 canvas in 32bit color mode:
This way you can use _RGB32 directly and use all possible combinations of Red, Green and Blue components:
PRINT "This is bright white over goldenrod."
@Petr:
Your code snippet above will only use the existing 16 colors of SCREEN 0, except you're using the _RGB function to select which of the attributes looks *closer* to the RGB values you give. That doesn't really use all possible colors.