The Buffington Effects Stepper Motor Controller will allow you to control a single low voltage stepper motor in one of two modes.
The first mode will allow you to control the speed that the controller will drive the motor. This mode will use 16 bits of data and will be able to drive the motor in either direction in an open-loop fashion. This mode is good for situations where you need something to move at exactly the speed that you request.
The second mode will allow you to position the stepper motor exactly where you want it to be. This is good for situations where you the mechanism linked to the motor will never change in mass and will repeat the exact same motion over and over with high precision. This mode is also open-loop so it will not be able to correct the position if the mechanism becomes tight and the motor cannot keep up with where it is commanded to go. In typical applications for stepper motors this shouldn't be a problem. If you are looking for a controller that can correct for mechanism friction and unexpected circumstances, take a look at the Buffington Effects DC Servo Motor Controller.
This controller will come with a configuration utility that will allow you to set which mode you want to use, the maximum acceleration and maximum speed of your motor, as well as the address for the motor. The board will have a provision for a limit switch so that the controller will be able to align itself when it is powered up.