3

我正在尝试使用 python 库 PyUSB 将数据发送到 USB 记忆棒。我正在使用的代码如下：

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')

但是我似乎收到以下错误：

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)

有人可以帮我解决这个错误并告诉我如何解决它

谢谢

4

2 回答 2

4

I just realized from the tags that you are using Ubuntu. In Ubuntu USB device permissions are tied to the USB device numbers. When Ubuntu ships it comes with global permissions for some standard devices (e.g. flash drives) so that non-root users can use these. However, it does not globally unlock USB devices because some USB devices could be harmful. Please see this post to understand how to modify the Ubuntu configuration (in particular /etc/udev/rules.d/40-basic-permissions.rules) in order to allow your device to be used by non-root users.

于 2013-02-26T02:21:43.253 回答
0

you have to do - on ubuntu:

sudo usermod -a -G uucp YOURUSER
sudo usermod -a -G dialout YOURUSER

and then 

sudo echo "SUBSYSTEM==\"usb\", ATTR{idVendor}==\"YOURVENDOR\", ATTR{idProduct}==\"YOURID\", MODE=\"666\"">/etc/udev/rules.d/99-YOURDEVICENAME.rules

in Your example:

 sudo echo "SUBSYSTEM==\"usb\", ATTR{idVendor}==\"090c\", ATTR{idProduct}==\"1000\", MODE=\"666\"">/etc/udev/rules.d/99-YOURDEVICENAME.rules
于 2020-03-30T18:34:07.530 回答