Scroll to navigation

Device::USB::DevInterface(3pm) User Contributed Perl Documentation Device::USB::DevInterface(3pm)

Device::USB::DevInterface

This class encapsulates a USB Device Interface and the methods that object would support.

NAME

Device::USB::DevInterface - Access a device interface returned by libusb.

VERSION

Version 0.38

SYNOPSIS

Device::USB:DevInterface provides a Perl object for accessing an interface of a configuration of a USB device using the libusb library.

    use Device::USB;

    my $usb = Device::USB->new();
    my $dev = $usb->find_device( $VENDOR, $PRODUCT );

    printf "Device: %04X:%04X\n", $dev->idVendor(), $dev->idProduct();
    $dev->open();

    my $cfg = $dev->config()->[0];
    my $inter = $cfg->interfaces()->[0];
    print "Interface:", $inter->bInterfaceNumber(),
       " name: ", $dev->get_string_simple($iter->iInterface()), 
       ": endpoint count: ", $inter->nNumEndpoints(), "\n";

See USB specification for an explanation of the attributes of an interface.

DESCRIPTION

This module defines a Perl object that represents the data associated with a USB device configuration's interface. The object provides read-only access to the important data associated with the interface.

METHODS

There are several accessor methods that return data from the interface. Each is named after the field that they return. These accessors include:
bInterfaceNumber
The 0-based number of this interface.
bAlternateSetting
Value used to select this alternate setting for the interface specified in bInterfaceNumber.
bNumEndpoints
Number of endpoints (excluding endpoint 0) available on this interface. If the value is 0, only the control interface is supported.
bInterfaceClass
Class code as specified by the USB-IF. A value of 0xff is a vendor-specific interface class.
bInterfaceSubClass
Subclass code specified by the USB-IF. If bInterfaceClass is not 0xff, this field must use only subclasses specified by the USB-IF.
bInterfaceProtocol
The InterfaceProtocol as specified by the USB-IF. A value of 0xff uses a vendor-specific protocol.
iInterface
Returns the index of the string descriptor describing this interface. The string can be retrieved using the method "Device::USB::Device::get_string_simple".
endpoints
Returns a list of endpoint objects associated with this interface.

DIAGNOSTICS

This is an explanation of the diagnostic and error messages this module can generate.

DEPENDENCIES

This module depends on the Carp, Inline and Inline::C modules, as well as the strict and warnings pragmas. Obviously, libusb must be available since that is the entire reason for the module's existence.

AUTHOR

G. Wade Johnson (gwadej at cpan dot org) Paul Archer (paul at paularcher dot org)

Houston Perl Mongers Group

BUGS

Please report any bugs or feature requests to "bug-device-usb@rt.cpan.org", or through the web interface at <http://rt.cpan.org/NoAuth/ReportBug.html?Device::USB>. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.

ACKNOWLEDGEMENTS

Thanks go to various members of the Houston Perl Mongers group for input on the module. But thanks mostly go to Paul Archer who proposed the project and helped with the development.

COPYRIGHT & LICENSE

Copyright 2006-2013 Houston Perl Mongers

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

2019-11-05 perl v5.30.0