I have a routine that changes the color (RGB) attributes on my
VGA adapter, but it doesn't work in the mode that I need.  
Specifically 68 hex.  An obscure mode, of course, but I need to
change the zillions of colors to 64 shade greyscale, but I do
not have the correct memory address for the pointer I need.

PLEASE, someone, I need the starting address, or maybe somewhere 
I can find it.  Thank you.