Blue,
C4 chip: A chip created by Capcom. This chip was used to handle the wireframe effects, perform more general trigonometric calculations, and to help out with sprite positioning and rotation. The chip was used in Mega Man X2 and Mega Man X3.
I got this info from the ever so trusty wikipedia!
Its actually really interesting!
http://en.wikipedia.org/wiki/Super_Nintendo_Entertainment_System