I was looking a way to prove my USB-SERIAL port and I found this code:
http://www.digitalmihailo.com/usb-programming-with-python-on-linux-pyusb-version/, but I have a problem because when I run this program, then show me up this message:
Traceback (most recent call last):
File "namefile.py", line 122 in <module>
main()
File "namefile.py", line 64, in main
raise ValueError('Device not found')
ValueError: Device not found
I already install the PyUSB library, but the result does not change. Someone can help me with this little problem.
Thank you much in advance.
If you are running your example in Linux you need to load the ACMtty module so you system makes a Serial USB device available for your user space.
As root and only if you have cdc-acm module compiled for your current kernel:
modprobe cdc-acm
Once this module is loaded and your device connected you should find a device named following this pattern: /dev/ttyACM*
You may have already installed the right user space tools and libraries but you also need to install the device.
Related
Problem
My application works well when in python-only and on my machine. I am attempting to deploy to a machine which has lesser privileges.
The basic script that I am attempting to run at the moment:
import logging
import os
os.environ['PYUSB_DEBUG'] = 'debug'
os.environ['PYUSB_LOG_FILENAME'] = 'C:\\path\to\log.txt'
logging.basicConfig(level=logging.DEBUG)
import usb.core
import usb.util
devices = [d for d in usb.core.find(find_all=True,
idVendor=0x0683,
idProduct=0x2008
)]
[print(d) for d in devices]
device = devices[0]
device.set_configuration()
The imports are a bit out of whack in this example file because the os.environ variable must be set before usb import or the logging won't be set up properly to get my log.txt from the usb module.
From Python
When I execute the above script on my machine, this is the resulting log.txt:
2022-05-13 06:50:02,760 DEBUG:usb.backend.libusb1:_LibUSB.__init__(<WinDLL 'C:\WINDOWS\system32\libusb-1.0.dll', handle 7ff8476e0000 at 0x20a622c18b0>)
2022-05-13 06:50:02,760 DEBUG:usb.backend.libusb1:_LibUSB.__init__(<WinDLL 'C:\WINDOWS\system32\libusb-1.0.dll', handle 7ff8476e0000 at 0x20a622c18b0>)
2022-05-13 06:50:02,766 INFO:usb.core:find(): using backend "usb.backend.libusb1"
2022-05-13 06:50:02,766 INFO:usb.core:find(): using backend "usb.backend.libusb1"
2022-05-13 06:50:02,767 DEBUG:usb.backend.libusb1:_LibUSB.enumerate_devices()
...
...(more logs past this point, but you can see that the core found the backend)
From pyinstaller executable
I am bundling using pyinstaller. I normally like to use --onefile, but I always verify functionality without --onefile. I am only doing the most basic build: pyinstaller --noconfirm path/to/script.py
The console error:
Traceback (most recent call last):
File "usb\backend\libusb0.py", line 738, in get_backend
File "Lib\site-packages\_pyinstaller_hooks_contrib\hooks\rthooks\pyi_rth_usb.py", line 57, in _load_libraryOSError: USB library could not be found
Traceback (most recent call last):
File "backend_test.py", line 15, in <module>
File "usb\core.py", line 1309, in find
usb.core.NoBackendError: No backend available
[9344] Failed to execute script backend_test
Note that the USB library failed to find a backend.
The fail log.txt when attempted to run the executable:
Traceback (most recent call last):
File "usb\backend\libusb0.py", line 738, in get_backend
File "Lib\site-packages\_pyinstaller_hooks_contrib\hooks\rthooks\pyi_rth_usb.py", line 57, in _load_library
OSError: USB library could not be found
2022-05-13 06:20:59,838 ERROR:usb.backend.libusb1:Error loading libusb 1.0 backend
Traceback (most recent call last):
File "usb\backend\libusb1.py", line 961, in get_backend
File "Lib\site-packages\_pyinstaller_hooks_contrib\hooks\rthooks\pyi_rth_usb.py", line 57, in _load_library
OSError: USB library could not be found
2022-05-13 06:20:59,840 ERROR:usb.backend.openusb:Error loading OpenUSB backend
Traceback (most recent call last):
File "usb\backend\openusb.py", line 745, in get_backend
File "Lib\site-packages\_pyinstaller_hooks_contrib\hooks\rthooks\pyi_rth_usb.py", line 57, in _load_library
OSError: USB library could not be found
2022-05-13 06:20:59,842 ERROR:usb.backend.libusb0:Error loading libusb 0.1 backend
Traceback (most recent call last):
File "usb\backend\libusb0.py", line 738, in get_backend
File "Lib\site-packages\_pyinstaller_hooks_contrib\hooks\rthooks\pyi_rth_usb.py", line 57, in _load_library
OSError: USB library could not be found
At the moment, I can tell that the failure is occurring in a pyinstaller hook. I don't understand precisely how this works, so the clue may be found somewhere in there.
Background & Research
Versioning
libusb==1.0.24b3
pyinstaller==4.3
pyinstaller-hooks-contrib==2022.4
pyusb==1.2.1
... (there is more, but I suspect that these are the critical-to-function packages)
libusb
Not sure why this installed the beta version. Interesting, but doesn't appear to be the smoking gun.
pyinstaller
Note that pyinstaller==4.3 is a bit out of date. This is a result of my overambitious IT department's antivirus. It doesn't appear to want to allow more recent versions of pyinstaller to build executables.
pyinstaller-hooks-contrib
This is a repository which contains several pyinstaller hooks. I know that these are "critical to function" for lots of modules, but I don't really know how this works. It is possible, even likely given that this is where something is failing, that my problem lies within this library OR with this library's interaction with the version of pyinstaller that I'm using. Version 2022.4 is the version that is installed when I python -m pip install pyinstaller.
pyusb
Current version.
Other Attempts Thus Far
I have been up and down the web and have spent a particularly long time with the SO question Pyusb on windows - no backend available. Many of the below attempts were based on that SO question, but there have been other sources as well.
There are more attempts than just these, but I have been at it long enough that I don't remember them all!
Bundling libusb-1.0.dll into Executable
It is possible to bundle dll files directly with the pyinstaller-created script using the datas directive. This was my first attempt and it worked... on my machine. As soon as I deployed, the script failed with a PermissionError. I suspect that "untrusted" dll's aren't allowed to be utilized on the target machine. My login on my machine has elevated privileges, explaining why it may have worked in my environment.
Installing libusb-win32-devel-filter.exe.
Simply didn't work.
Including C:\\Windows\\System32 on PATH
I verified that the PATH variable contained C:\\Windows\\System32, which I also verified contains the proper dll file.
Specify backend
When I modify the script to specify the backend:
...
import usb.backend.libusb1 as libusb1
be = libusb1.get_backend(find_library=lambda x: "C:\\WINDOWS\\system32\\libusb-1.0.dll")
devices = [d for d in usb.core.find(find_all=True,
idVendor=0x0683,
idProduct=0x2008,
backend=be)]
...
There is no change in behavior. I do see in the log when running in python (not pyinstaller) that the backend is immediately found:
2022-05-13 07:22:12 USBN1LPGDKWXD3 usb.backend.libusb1[6880] DEBUG _LibUSB.__init__(<WinDLL 'C:\Windows\System32\libusb-1.0.dll', handle 7ff840bd0000 at 0x190eadbe820>)
2022-05-13 07:22:12 USBN1LPGDKWXD3 usb.backend.libusb1[6880] DEBUG _LibUSB.enumerate_devices()
2022-05-13 07:22:12 USBN1LPGDKWXD3 usb.backend.libusb1[6880] DEBUG _LibUSB.get_device_descriptor(<usb.backend.libusb1._Device object at 0x00000190EAE58EB0>)
2022-05-13 07:22:12 USBN1LPGDKWXD3 usb.backend.libusb1[6880] DEBUG _LibUSB.get_device_descriptor(<usb.backend.libusb1._Device object at 0x00000190EAE58F40>)
...
Install libusb
No change.
Modify pyinstaller and pyinstaller-hooks-contrib versions
Tried pyinstaller==4.10 and python-hooks-contrib==2022.3, which appear to be "compatible" releases.
I would like to try to build the pyinstaller script by excluding the pyusb from pyinstaller-hooks-contrib, but I'm not sure how to do this.
Other Clues....
While looking in pyinstaller-hooks-contrib, I'm seeing the way to access DLL files is through ctypes.WinDLL.
import ctypes
print('ctypes.WinDLL', ctypes.WinDLL('libusb-1.0.dll'))
Result when running from python: <WinDLL 'libusb-1.0.dll', handle 7ff831cc0000 at 0x21076e9adf0>
Result when running from pyinstaller: ctypes.WinDLL <PyInstallerWinDLL 'libusb-1.0.dll', handle 7ff83d400000 at 0x201a9f39fa0>
I'm still not sure why this works the way that it does, but my initial instincts were correct when I had tried to include libusb-1.0.dll in the pyinstaller package. Unfortunately, there is apparently an issue with the windows implementation of the libusb-1.0.dll (I'm not making that assertion, I'm quoting another SO answer).
The answer, for me, was to add libusb0.dll to my pyinstaller build directory instead of the more recent libusb-1.0.dll:
a = Analysis(['examples\\backend_test.py'],
pathex=[],
binaries=[],
datas=[('C:\\Windows\\System32\\libusb0.dll', '.'),],
hiddenimports=[],
...])
I can't believe that it was this simple in my case, but there it is...
I am running the following blink program on my raspberry pi pico. I am using circuit python.
from machine import Pin
import time
led = Pin(13, Pin.OUT)
while True:
led(1)
time.sleep(1)
led(0)
time.sleep(1)
When I run it though it gives this error:
Traceback (most recent call last):
File "code.py", line 1, in <module>
ImportError: no module named 'machine'
I have tried to find if I need to download a library file or any thing about the machine module, but I have found nothing. If you know why it can't find the machine module that would be greatly appreciated.
Your code is for micropython. Circuitpython is different. See here https://learn.adafruit.com/circuitpython-essentials/circuitpython-digital-in-out
from digitalio import DigitalInOut, Direction, Pull
led = DigitalInOut(board.LED)
I was having same issue and a search found this thread.
I changed the Interpreter setting in Thonny (under options) from Local Python 3, to MicroPython (Raspberry Pi Pico)
I think you are using the incorrect uf2 file as the official (stable) version is not out as of writing this.
In order to check this, type the following in MircoPython's command line:
import sys
sys.implementation
(name='micropython', version=(1, 19, 1), _machine='Raspberry Pi Pico with RP2040', _mpy=4102)
If the response shows "Pico" and not "Pico W" then copy the latest version from here and copy it onto your Pico W (in USB mode)
I'm using Ubuntu 20.10 and I am relatively new to Linux so I would like to kindly ask you to tell me if there is any info needed.
I am trying to install Ableton Live 10 in Ubuntu but I get this when I try to wine program_name.exe
wine Ableton\ Live\ 10\ Suite.exe
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "ssl\__init__.py", line 59, in <module>
import os, sys
ImportError: No module named os
wine: Unhandled exception 0x80000003 in thread 2b at address 000000007BCDDFCC (thread 002b), starting debugger...
0x000000007bcddfcc DbgBreakPoint in ntdll: int $3
Modules:
Module Address Debug info Name (171 modules)
ELF 7a800000- 7aa0e000 Deferred opengl32<elf>
\-PE 7a850000- 7aa0e000 \ opengl32
ELF 7b000000- 7b0e2000 Dwarf kernelbase<elf>
\-PE 7b010000- 7b0e2000 \ kernelbase
.... and at the end
System information:
Wine build: wine-5.0 (Ubuntu 5.0-3ubuntu1)
Platform: x86_64
Version: Windows 7
Host system: Linux
Host version: 5.8.0-43-generic
I think that I need to have to install a os and sys file but I have no idea what these are except that there maybe python files. I had the same error with a not existing ssl file which I downloaded and it worked but now I am stuck here.
I've tried to look for some solution online but there are either not the right error or the problem has to do with writing code instead of installing and so I don't know to solve it by myself. I hope you guys can help me out..
Can anyone suggest a solution? Thanks :D
I'm fairly new to python and I'm trying to get Pybluez to work for me.
Here is what happens when i try to discover bluetooth devises.
import bluetooth
nearby_devices = bluetooth.discover_devices()
Traceback (most recent call last):
File "<stdin>",line1,in <module>
AttributeError: 'module' object has no attribute 'discover_devices'
I'm on windows 8.1, python 2.7.10, pybluez 0.21
I had the same problem, I did the mistake of naming my program file bluetooth.py , which confused python for the package resolution, you should look out for this silly mistake if this is the case .
If this is not the case then try to put your file in the directory where your bluetooth directory (in my case, C:\Python27\Lib\site-packages) is located and then run it from there, it worked for me.
I faced same issue because i have taken my file name bluetooth.py.For that reason python unable to understand which file be execute.
Please rename your file then it will be work.
rename the file to any other nameļ¼ except "bluetooth.py"
Now it's been like 3 days and I still don't manage. Maybe someone can help.
I want to send a control command to a midi device, via python, on a mac. Everywhere I see, the happy answer is to use pygame, but truth is that the pygame version on the mac lacks that functionality.
When I try run this two lines :
from pygame import midi
midi.init()
I get the following error:
Traceback (most recent call last):
File "midi_send.py", line 9, in <module>
midi.init()
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site- packages/pygame/midi.py", line 71, in init
import pygame.pypm
ImportError: No module named pypm
I've looked and looked and all I find is dead ends.
Has anyone actually tried using pygame to write to a midiport, on a mac? is there an alternative that doesn't include getting stuck in some gcc compile error something replace line N of somemidi.o file somewhere in /etc/whatever/whatever?
Sorry for being frustrated...
You could try using the rtmidi-python library (or older and slightly different pyrtmidi) - both based on rtmidi which provides for straightforward sending of MIDI Control and Notes:
import rtmidi_python as rtmidi
midi_out = rtmidi.MidiOut()
midi_out.open_port(0)
midi_out.send_message([0x90, 48, 100]) # Note on
midi_out.send_message([0x80, 48, 100]) # Note off