Is libusb installed ?

1st Official Post

    Hi,

    Managed to install python modules (pywws), but when I try to read from an USB attached device, I get the error :

    Quote


    usb.core.NoBackendError: No backend available

    People say this is due to the fact that package libusb is not installed.
    Can anyone of the developers tell me if this is the case, please ?
    I compiled the LE I'm using myself, but if I have to include libusb when compiling, I can't find a guide how to do that.....

    Thanks,
    Hans

    It's already included:

    Code
    # ls /usr/lib/libusb*
/usr/lib/libusb-0.1.so.4      /usr/lib/libusb-0.1.so.4.4.4  /usr/lib/libusb-1.0.so        /usr/lib/libusb-1.0.so.0      /usr/lib/libusb-1.0.so.0.1.0  /usr/lib/libusb.so

    Thanks for answering my question.
    Should have seen that myself.....( slowly disappearing around the corner....)

    However, the python script I'm using is apparently unable to find this lib location, because
    the no backend error is still there.

    Hi lrusak,

    Downloaded the OpenELEC.tv-WeeWXOS branch, and started compiling.
    It gets a long way, but when trying to compile libirman it stops with the error:

    UNPACK libirman
    gzip: stdin: not in gzip format

    and the compilations errors out.

    Any idea how to fix this, or how to determine where this goes wrong ?

    Thanks,
    Hans

    • Official Post
    Quote from phloks


    Hi lrusak,

    Downloaded the OpenELEC.tv-WeeWXOS branch, and started compiling.
    It gets a long way, but when trying to compile libirman it stops with the error:

    I didn't mean to use that branch, because that branch won't work.

    I mean you can copy the folder or just the package.mk of the package you need.

    Quote from lrusak

    I didn't mean to use that branch, because that branch won't work.

    I mean you can copy the folder or just the package.mk of the package you need.

    Ok,
    I probably do not understand how this works.
    I git cloned the current OE master branch, and created two extra directories under packages/python/system called pyserial and pyusb.
    And of course, I copied the package.mk files in their respctive directories.
    After that I compiled everything (had to change the URL for libssh-0.7.3 to another site because until now only 0.7.2 is available), and I got an nimage.

    It seems however that pyusb and pyserial have not been included in the build.

    Is there something else I need to do first ?

    Thanks,
    Hans

    Edited once, last by phloks (July 14, 2016 at 11:51 AM).

    Quote from escalade


    You'll need to modify scripts/image to install it, or add it to another package's dependencies.

    Ok,
    Thanks for answering my question.
    I'm looking at scripts/image right now, but I don't see where to add in references to pyserial and pyusb.

    Is there documentation on how to do this ?

    Thanks,
    Hans