[maxmsp] midi controlled tunable oscillator inside poly~ object

hey everybody.
i know this probably sounds a bit stoopid but i can?t figure out.
how can i make a saw~,rect~...( oscillator ) playable with midi...
like with mtof but then still have the possibilty to tune it.
i want to play it with my keyboard and still tune it seperately. i dont want to tune the midi-value ...i?d like to change either the incoming or outgoing frequency without loosing the midiscale ...simply changing the whole frequency..