pycomedi 0.9

An object-oriented interface for the Comedi drivers.

This package provides an object-oriented interface to the Comedi drivers. The standard Python interface bundled with Comedilib is a simple SWIG clone of the C interface. In pycomedi, we convert the functions into class methods (see pycomedi.classes), so you don’t have to worry about dragging around opaque types like comedi_t * device pointers. We also bundle related constants together in _Enums and _Flags (see pycomedi.constants), to make handling common operations like flag manipulations simpler. Finally, there are a number of utility classes (see pycomedi.utility) to make common tasks like creating instructions or reading hardware-timed analog input easier.

Installation

Packages

Gentoo

I’ve packaged pycomedi for Gentoo. You need layman and my wtk overlay. Install with:

# emerge -av app-portage/layman
# layman --add wtk
# emerge -av dev-python/pycomedi

Dependencies

If you’re installing by hand or packaging pycomedi for another distribution, you’ll need the following dependencies:

Package	Purpose	Debian	Gentoo
NumPy	?	python-numpy	dev-python/numpy
SciPy	testing	python-scipy	sci-libs/scipy
Comedi	Comedilib interface	python-comedilib	sci-libs/comedilib [1]
nose	testing	python-nose	dev-python/nose
Cython	Comedilib interface	cython	dev-python/cython
python-kmod	Optional ext. info.		dev-python/python-kmod [1]

[1] (1,2)

In the wtk overlay.

If python-kmod is installed, you will get additional module information from the info.py demo program. If it is not installed, everything will still work, but info.py will only be able to get the module version, not the kernel version, staging-ness, parameters, etc.

Installing by hand

Pycomedi is available as a Git repository:

$ git clone git://tremily.us/pycomedi.git

See the homepage for details. To install the checkout, run the standard:

$ python setup.py install

Usage

See the examples in the doc directory.

Testing

Run integration tests with:

$ nosetests --with-doctest --doctest-extension=txt doc

The analog integration tests read from analog input channels 0 through 3, and write to analog output channels 0 and 1, so you’ll need a board with that many channels. You should also make sure that the analog output channels aren’t plugged into anything sensetive, since the tests sweep their output around over a reasonable chunk of the channel range. Some of the internal unit tests also write, so it’s safest to just disconnect all digital lines and analog outputs before running the tests.

Run both integration tests and internal unit tests with:

$ ./test.sh

Licence

This project is distributed under the GNU General Public License Version 2 or greater.

Author

W. Trevor King [e-mail]