[PD] servo control

[Martin Peach]

p d wrote:
> Hello all,
> I'm trying to control motors from pd. A few post in the pd-list deals
>  with that problems, but from user-experience, i would like to know which
>  one is the easiest one . The Parrallax Servo Controller seams to be a
>  cheap solution, like Martin Peach explained but how is it working? Is
>  it possible to control a bipolar motor (I need them to drive a toothed
>  rack backward and forward)? Any help is apreciated. Thank you.
> pablo
>
>   
What motor do you have? Is it a servo/stepper/dc motor? Bipolar steppers 
or reversible dc motors need to be controlled by an H-bridge circuit. 
Servos can be hacked to rotate continuously but usually only have a 180 
degree range of motion. If you have an H-bridge circuit you could use 
the Arduino with pd to control it. The servo controller just needs a 
serial port.
Here's some info about steppers: 
http://www.piclist.com/techref/piclist/jal/DrivingBipolarStepperMotors.htm

Martin