As you might guess, I tend to do lots of video game cover modules, and most notably the NES Mega Man series (good music, nice and simple, no extra channels, and so on).
Recently, Capcom released Mega Man 9 in the 8-bit style, down to the music, but they've taken to using some tricks the NES sound hardware was capable of, that I have no clue how I'd replicate in a module.
The trick in question is the ability to change the square used between frames (for a prime example, listen to the password music from Punch-Out!!'s NSF. Each note starts as a 12.5 square, then quickly changes to 25 and then 50 for sustain) while at the same time doing a portamento between notes (I'm using the XM '3XX' effect for this).
How in the hell would I manage to pull this off without having to use two extra channels?
