Part of me wants to ask... why bother with the computer when you can make the sound already with something so simple?
Anyways, what you need is either the 'voltage drop' (i.e. connect the + of the battery to the first two pins of a potentiometer, connect the + of the effect power to the last pin and connect the - of the effect power to the - of the battery) or a 'voltage divider' (i.e. connect the
- of the battery to the first pin of the poti, the middle pin of the
poti to the + of the effect power and connect the last pin of the poti to the - of the battery and the - of the effect power...or something like that).
I've always felt that it's quite a bit of work to simulate the nonlinear behaviour of analog electronics in the superlinear world of digital synthesis. Unless you know *heaps* of math. The problem with PD and it's brethren is that it is far too predictable. I don't consider using [random] a way out of this trap, since the results are still linear... i.e. linearly randomized, making them quite characterless.
Probably the simplest way to get a nonlinear kind of sound out of PD is by chaining different oscillators together in feedback AM or FM situations. But since you have to use [send~] and [receive~] pairs to make the feedback loops (to avoid the dreaded "DSP loop detected" message), it's never really responding in realtime to what's going on (like an analog circuit where all the electrons move more or less simultaneously), so it can never really get to this nonlinear nirvana I dream of....
OK, rambled enough... back to work.
d.