Yes, I have two input values (possibly a third but the third is a button that I'm going to do analog read of its current) it's a joystick controller.
Some weird things are happening with my joystick now too. I am hoping it's not the hardware (I soldered it to a breakout board. All of the components were bought at SparkFun). After a while, at least today my potentiometer is reading a smaller and smaller range. Was initally 0 - 1023 and now it's down to 100 to 800 (after 30 mins to an hour of testing and reading analog input). I'll have to take a look at it when I'm home again.
On topic, what I want is to get the the motor to move one direction when going from the range of 507 - 1023 with varying speed depending on how far up the joystick is pressed. Same for the reverse direction and same for the axis of the other potentiometer. It's a stepper motor so I want the range of the speed of the motor to be from 60 to 150 rpm. 150rpm being the the top and bottom values (0 and 1023).
From my first post, I don't want the motors to move from a range close to the midpoint of the two potentiometers. That's why I want 503 - 507 needs to have rpm speed of 0.
This is the joystick/potentiometers I ordered from SF
Source: http://www.sparkfun.com/commerce/product_info.php?products_id=9032