Alright.. Although usually it is hard to find a good tutorial on the snes, I
think Grog did an amazing job with his HDMA tutorial. Qwertie also has some
nice information on the subject. Because of this, I'm not going to bother,
but I did write some comments and made some edits in Grog's doc. If you any
questions after reading it ask me or check Qwertie.