Apple2 control characters?

Hi!  A while ago, I ported some cc65 code from CBM to Apple2.  While I was porting the code, I forgot to clean up the control characters, and the results were random attribute changes, i.e. inverse characters and a switch back to 40-column mode.  This leads me to believe that, like the CBM models, the Apple2 also had control characters.  Where online can I find a list of Apple2 control characters?