BillyNoSocks as and example, can you confirm what you are seeking to do and what midi equipment do you have at your disposal.
And, is this for live or studio use? (a DAW with midi may do the trick at home but not practical on stage.
You wish to manipulate the pitch of the pitch effect? it may be in steps as opposed to a "whammy" style smooth pitch transition.
Explain further and lets see what solutions can be presented