bb_pystepper is a Python module for controlling stepper motors with the BeagleBone Black. The code by default uses full-stepping.

• Python 2.xx
• Adafruit_BBIO

After installing Adafruit_BBIO and downloading the bb_pystepper code to the BeagleBone (log in via SSH and then git clone https://github.com/petebachant/bb_pystepper.git), the module can be imported into a Python script or run from a Python interpreter. For example:

$ cd bb_pystepper
$ python
>>> from bb_pystepper import Stepper
>>> mystepper = Stepper()
>>> mystepper.rotate(180, 10) # Rotates motor 180 degrees at 10 RPM
>>> mystepper.rotate(-180, 5) # Rotates motor back 180 degrees at 5 RPM
>>> mystepper.angle
0.0

• By default the GPIO pins used are P8_13, P8_14, P8_15, and P8_16. These can be changed by modifying the Stepper.pins list.
• By default the Stepper.steps_per_rev parameter is set to 2048 to match my motor (it has a built-in gearbox).
• The code doesn't keep track of where it ends in the sequence of pins. It simply sets all pins low after a move. This means there could be some additional error in the Stepper.angle variable if the amount of steps moved is not divisible by 4.

bb_pystepper Copyright (c) 2013 Peter Bachant

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.