NeoPixels not working at all (error on Pi)

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1

Hey guys,
I followed the guide as well as I could, but keep getting

    Traceback (most recent call last):
      File "strandtest.py", line 9, in <module>
        from rpi_ws281x import *
    ImportError: No module named rpi_ws281x

Any insights as to what could cause this and how to fix?

Thanks!
-Chris

2

Hey Chris,

Hmm it seems like our bash script might be playing up a bit!

You can just install that library manually using:

sudo pip install rpi_ws281x

Hope this helps!

3

Thanks Owen!

I tried running that code but get
sudo: pip: command not found

4

So I used
sudo apt-get install python-pip

to install pip, but now running your code gives

    Looking in indexes: https://pypi.org/simple, https://www.piwheels.org/simple
    Requirement already satisfied: rpi_ws281x in /usr/local/lib/python2.7/dist-packages/rpi_ws281x-1.0.0-py2.7-                                        linux-armv7l.egg (1.0.0)

and I still get the same result when attempting to run the strandtest.

5

Just to confuse things futher, I looked in the directory and tried all the other tests, they all get the same result except for lowlevel.py which seems to work, but only on the first 16 LED’s

6

Hi Chris,

pip may be assigned to the wrong version of python. I can see there are some similar errors in the forum thread for that guide:

We’ll have to have a bit of a dig and see what the root cause is, though I suspect it’s mostly just an issue with python versions.

7

Thanks heaps for your reply Oliver!

Let me know if there’s anything I can do to help diagnose. I even tried formatting my SD card and running a fresh install of Raspbian, and doing nothing but the guide and still had the same issue so hopefully that rules out anything else I’ve done on this Pi.

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8

FWIW, these are the results I got for pip install

pi@raspberrypi4:~ $ sudo pip install rpi_ws281x
Looking in indexes: Simple index, piwheels - Simple index
Collecting rpi_ws281x
Downloading https://files.pythonhosted.org/packages/c2/cf/0c713dcbb08de087619f6f6917cfe68c4ebf6ef828ede4d63a3bf421f1bf/rpi_ws281x-4.3.1-cp27-cp27mu-linux_armv7l.whl (79kB)
100% |████████████████████████████████| 81kB 808kB/s
Installing collected packages: rpi-ws281x
Successfully installed rpi-ws281x-4.3.1
pi@raspberrypi4:~ $ sudo python /home/pi/rpi_ws281x/python/examples/strandtest.py -c
Press Ctrl-C to quit.
Color wipe animations.
Theater chase animations.
Rainbow animations.
Color wipe animations.
Theater chase animations.
Rainbow animations.
^Cpi@raspberrypi4:~ $ ^C

The WS281x is in a directory, and the path is in the command line to execute.

Initially, I too had that error, using pip3 install of the rpi_ws281x. The command line must use just “python” as the script downloaded from here is not python3 code.

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