我正在尝试使用python库PyUSB将数据发送到usb棒。我使用的代码如下：
import usb.core
import usb.util
# find our devices
#dev = usb.core.find(idVendor=0xfffe, idProduct=0x0001)
dev = usb.core.find(idVendor=0x090c, idProduct=0x1000)
# was it found?
if dev is None:
raise ValueError('Device not found')
# set the active configuration. With no arguments, the first
# configuration will be the active one
dev.set_configuration()
# get an endpoint instance
cfg = dev.get_active_configuration()
interface_number = cfg[(0,0)].bInterface_number
alternate_setting = usb.control.get_interface(interface_number)
intf = usb.util.find_descriptor(
cfg, bTnerfaceNumber = interface_number,
bAlternateSettings = alternate_setting
)
ep = usb.util.find_descriptor(
intf,
# match the first OUT endpoint
custom_match =
lambda e:
usb.util.endpoint_direction(e.bEndpointAddress) ==
usb.util.ENDPOINT_OUT
)
assert ep is not None
# write the data
ep.write('test')
然而，我似乎得到了以下错误：
Traceback (most recent call last):
File "/home/usman/Desktop/c_code/libusb_test_data/pyusb_code/send_data_rev_one.py", line 14, in <module>
dev.set_configuration()
File "/usr/local/lib/python2.7/dist-packages/usb/core.py", line 554, in set_configuration
self._ctx.managed_set_configuration(self, configuration)
File "/usr/local/lib/python2.7/dist-packages/usb/core.py", line 91, in managed_set_configuration
self.managed_open()
File "/usr/local/lib/python2.7/dist-packages/usb/core.py", line 70, in managed_open
self.handle = self.backend.open_device(self.dev)
File "/usr/local/lib/python2.7/dist-packages/usb/backend/libusb1.py", line 494, in open_device
_check(_lib.libusb_open(dev.devid, byref(handle)))
File "/usr/local/lib/python2.7/dist-packages/usb/backend/libusb1.py", line 403, in _check
raise USBError(_str_error[ret], ret, _libusb_errno[ret])
USBError: [Errno 13] Access denied (insufficient permissions)
有人能告诉我这个错误吗
感谢
我刚刚从标签中意识到您正在使用Ubuntu。在Ubuntu中，USB设备权限与USB设备编号绑定。当Ubuntu发布时，它为一些标准设备(例如闪存驱动器(提供了全局权限，以便非root用户可以使用这些设备。然而，它不会全局解锁USB设备，因为某些USB设备可能有害。请参阅这篇文章，了解如何修改Ubuntu配置(特别是/etc/udev/rules.d/40 basic permissions.rules(，以允许非root用户使用您的设备。
你必须在ubuntu:上做
sudo usermod -a -G uucp YOURUSER
sudo usermod -a -G dialout YOURUSER
然后
sudo echo "SUBSYSTEM=="usb", ATTR{idVendor}=="YOURVENDOR", ATTR{idProduct}=="YOURID", MODE="666"">/etc/udev/rules.d/99-YOURDEVICENAME.rules
在您的示例中：
sudo echo "SUBSYSTEM=="usb", ATTR{idVendor}=="090c", ATTR{idProduct}=="1000", MODE="666"">/etc/udev/rules.d/99-YOURDEVICENAME.rules