Wrong Elf Class error when trying example python on raspberry pi 4

[rvijgen]

When I run the python example on a fresh up to date raspbian install on Raspberry Pi4 I get the following error

Traceback (most recent call last):
File "/home/pi/shared/e-Paper/RaspberryPi_JetsonNano/python/examples/epd_2in7b_test.py", line 11, in
from waveshare_epd import epd2in7b
File "/home/pi/shared/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epd2in7b.py", line 32, in
from . import epdconfig
File "/home/pi/shared/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epdconfig.py", line 238, in
implementation = JetsonNano()
^^^^^^^^^^^^
File "/home/pi/shared/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epdconfig.py", line 116, in init
self.SPI = ctypes.cdll.LoadLibrary(so_filename)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib/python3.11/ctypes/init.py", line 454, in LoadLibrary
return self._dlltype(name)
^^^^^^^^^^^^^^^^^^^
File "/usr/lib/python3.11/ctypes/init.py", line 376, in init
self._handle = _dlopen(self._name, mode)
^^^^^^^^^^^^^^^^^^^^^^^^^
OSError: /home/pi/shared/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/sysfs_software_spi.so: wrong ELF class: ELFCLASS64

[LoieBensbane]

I'm experiencing the same issue with a fresh install of Bookworm on a raspberry pi zero W.

Linux raspberrypi 6.1.0-rpi4-rpi-v6 #1 Raspbian 1:6.1.54-1+rpt2 (2023-10-05) armv6l

Traceback (most recent call last):
File "/home/username/e-Paper/RaspberryPi_JetsonNano/python/examples/epd_2in13g_test.py", line 11, in
from waveshare_epd import epd2in13g
File "/home/username/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epd2in13g.py", line 32, in
from . import epdconfig
File "/home/username/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epdconfig.py", line 238, in
implementation = JetsonNano()
^^^^^^^^^^^^
File "/home/username/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epdconfig.py", line 116, in init
self.SPI = ctypes.cdll.LoadLibrary(so_filename)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib/python3.11/ctypes/init.py", line 454, in LoadLibrary
return self._dlltype(name)
^^^^^^^^^^^^^^^^^^^
File "/usr/lib/python3.11/ctypes/init.py", line 376, in init
self._handle = _dlopen(self._name, mode)
^^^^^^^^^^^^^^^^^^^^^^^^^
OSError: /home/username/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/sysfs_software_spi.so: wrong ELF class: ELFCLASS64

[jcolladosp]

Similar error on raspberry pi 4, last version of Raspberry pi os:
File "/home/marco/democode/e-Paper/RaspberryPi_JetsonNano/python/examples/epd_7in5b_V2_test.py", line 11, in <module> from waveshare_epd import epd7in5b_V2 File "/usr/local/lib/python3.11/dist-packages/waveshare_epd-0.0.0-py3.11.egg/waveshare_epd/epd7in5b_V2.py", line 32, in <module> from . import epdconfig File "/usr/local/lib/python3.11/dist-packages/waveshare_epd-0.0.0-py3.11.egg/waveshare_epd/epdconfig.py", line 238, in <module> implementation = JetsonNano() ^^^^^^^^^^^^ File "/usr/local/lib/python3.11/dist-packages/waveshare_epd-0.0.0-py3.11.egg/waveshare_epd/epdconfig.py", line 119, in __init__ raise RuntimeError('Cannot find sysfs_software_spi.so') RuntimeError: Cannot find sysfs_software_spi.so

[chrisvanberg]

Similar issue on Raspberry Pi B+ running Raspbian 32bits

It seems that the sysfs_software_spi.so is not compiled for 32 bit architecture.

[jcolladosp]

Similar issue on Raspberry Pi B+ running Raspbian 32bits

It seems that the sysfs_software_spi.so is not compiled for 32 bit architecture.

But if you see epdconfig.py file, sysfs_software_spi.so is only necesary for JetsonNano, no Raspberry Pi, so I dont know why but its geting the wrong system:

e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epdconfig.py

Line 114 in 4822c07

so_filename = os.path.join(find_dir, 'sysfs_software_spi.so')

[LoieBensbane]

Similar issue on Raspberry Pi B+ running Raspbian 32bits

It seems that the sysfs_software_spi.so is not compiled for 32 bit architecture.

But if you see epdconfig.py file, sysfs_software_spi.so is only necesary for JetsonNano, no Raspberry Pi, so I dont know why but its geting the wrong system:

e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epdconfig.py

Line 114 in 4822c07

so_filename = os.path.join(find_dir, 'sysfs_software_spi.so')

Lines 233-241 seem to be the answer to why it's getting the wrong system: JetsonNano is the else condition. It's not finding what it expects to at the path used to check that the code is being run on a raspberry pi.

[jcolladosp]

Similar issue on Raspberry Pi B+ running Raspbian 32bits

It seems that the sysfs_software_spi.so is not compiled for 32 bit architecture.

But if you see epdconfig.py file, sysfs_software_spi.so is only necesary for JetsonNano, no Raspberry Pi, so I dont know why but its geting the wrong system:

e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epdconfig.py

Line 114 in 4822c07

so_filename = os.path.join(find_dir, 'sysfs_software_spi.so')

Lines 233-241 seem to be the answer to why it's getting the wrong system: JetsonNano is the else condition. It's not finding what it expects to at the path used to check that the code is being run on a raspberry pi.

I can confirm that on Raspberry Pi 4 with Raspberry Pi OS 64 bits, that file doesn't exist: /sys/bus/platform/drivers/gpiomem-bcm2835

[LoieBensbane]

Similar issue on Raspberry Pi B+ running Raspbian 32bits

It seems that the sysfs_software_spi.so is not compiled for 32 bit architecture.

But if you see epdconfig.py file, sysfs_software_spi.so is only necesary for JetsonNano, no Raspberry Pi, so I dont know why but its geting the wrong system:

e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epdconfig.py

Line 114 in 4822c07

so_filename = os.path.join(find_dir, 'sysfs_software_spi.so')

Lines 233-241 seem to be the answer to why it's getting the wrong system: JetsonNano is the else condition. It's not finding what it expects to at the path used to check that the code is being run on a raspberry pi.

I can confirm that on Raspberry Pi 4 with Raspberry Pi OS 64 bits, that file doesn't exist: /sys/bus/platform/drivers/gpiomem-bcm2835

I changed my epdconfig.py by cutting the path back to '/sys/bus/platform/drivers' so that it would at least proceed using the Rasberry Pi code.

A new error appears! (kindof... I'll explain after the Traceback)

INFO:root:epd2in13g Demo
INFO:root:init and Clear
DEBUG:waveshare_epd.epd2in13g:e-Paper busy H
DEBUG:waveshare_epd.epd2in13g:e-Paper busy release
Traceback (most recent call last):
File "/home/username/e-Paper/RaspberryPi_JetsonNano/python/examples/epd_2in13g_test.py", line 23, in
epd.init()
File "/home/username/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epd2in13g.py", line 144, in init
self.SetWindow()
File "/home/username/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epd2in13g.py", line 94, in SetWindow
self.send_data(self.Source_BITS/256)
File "/home/username/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epd2in13g.py", line 81, in send_data
epdconfig.spi_writebyte([data])
File "/home/username/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epdconfig.py", line 63, in spi_writebyte
self.SPI.writebytes(data)
TypeError: Non-Int/Long value in arguments: b65691e0.

This is the same error I was seeing when running the same code on a freshly installed and prepared image of Bullseye (with an unmodified epdconfig.py). Bookworm removed the driver, but there's still another underlying problem.

It's worth noting that the C demo code works flawlessly on both. Unfortunately, I don't speak C.

[LoieBensbane]

Found the missing piece of the puzzle. The python demo now runs for me without issue.

To summarize the changes made:

At line 233 of /home/username/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epdconfig.py I changed /sys/bus/platform/drivers/gpiomem-bcm2835 to /sys/bus/platform/drivers

At line 94 of /home/username/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epd2in13g.py I changed self.send_data(self.Source_BITS/256) to self.send_data(self.Source_BITS//256)

At line 96 of /home/username/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epd2in13g.py I changed self.send_data(self.Gate_BITS/256) to self.send_data(self.Gate_BITS//256)

[jcolladosp]

Similar issue on Raspberry Pi B+ running Raspbian 32bits

It seems that the sysfs_software_spi.so is not compiled for 32 bit architecture.

But if you see epdconfig.py file, sysfs_software_spi.so is only necesary for JetsonNano, no Raspberry Pi, so I dont know why but its geting the wrong system:

e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epdconfig.py

Line 114 in 4822c07

so_filename = os.path.join(find_dir, 'sysfs_software_spi.so')

Lines 233-241 seem to be the answer to why it's getting the wrong system: JetsonNano is the else condition. It's not finding what it expects to at the path used to check that the code is being run on a raspberry pi.

I can confirm that on Raspberry Pi 4 with Raspberry Pi OS 64 bits, that file doesn't exist: /sys/bus/platform/drivers/gpiomem-bcm2835

I changed my epdconfig.py by cutting the path back to '/sys/bus/platform/drivers' so that it would at least proceed using the Rasberry Pi code.

A new error appears! (kindof... I'll explain after the Traceback)

INFO:root:epd2in13g Demo INFO:root:init and Clear DEBUG:waveshare_epd.epd2in13g:e-Paper busy H DEBUG:waveshare_epd.epd2in13g:e-Paper busy release Traceback (most recent call last): File "/home/username/e-Paper/RaspberryPi_JetsonNano/python/examples/epd_2in13g_test.py", line 23, in epd.init() File "/home/username/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epd2in13g.py", line 144, in init self.SetWindow() File "/home/username/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epd2in13g.py", line 94, in SetWindow self.send_data(self.Source_BITS/256) File "/home/username/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epd2in13g.py", line 81, in send_data epdconfig.spi_writebyte([data]) File "/home/username/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epdconfig.py", line 63, in spi_writebyte self.SPI.writebytes(data) TypeError: Non-Int/Long value in arguments: b65691e0.

This is the same error I was seeing when running the same code on a freshly installed and prepared image of Bullseye (with an unmodified epdconfig.py). Bookworm removed the driver, but there's still another underlying problem.

It's worth noting that the C demo code works flawlessly on both. Unfortunately, I don't speak C.

What python version are you using?
If you are using Raspberry Pi you only need to change the last ifs to this:
implementation = RaspberryPi()

[LoieBensbane]

What python version are you using?

I'm using Python 3.11.2

If you are using Raspberry Pi you only need to change the last ifs to this: implementation = RaspberryPi()

That is much more elegant. Thank you.

[mendhak]

Unfortunately this seems to break my project as I have been referencing this repo as a module, to allow users to use different Waveshare displays. To be specific, using it with the October 10th Raspberry Pi OS. It's also not limited to Raspberry Pi 4, it does happen on Raspberry Pi Zero, Zero two, etc.

It would be appreciated if a waveshare team member could give some attention to this issue and implement a more reliable fix on the epdconfig instead, so users don't have to edit a file to get the waveshare code working with latest Raspberry Pi OS. Sorry not sure who that would be @SSYYL @kmanc @waveshareteam ?

[mendhak]

For reference, here is how Adafruit detect Raspberry Pi: https://github.com/adafruit/Adafruit_Python_GPIO/blob/a12fee39839665966bd124fd22588b2c87ced9d2/Adafruit_GPIO/Platform.py#L84-L113

This thread has some useful suggestions too, looking for the Model: line in cat /proc/cpuinfo: https://raspberrypi.stackexchange.com/a/139704/540

Or looking for the existence of the /etc/rpi-issue file: https://raspberrypi.stackexchange.com/a/140325/540

[Marv2190]

Unfortunately this seems to break my project as I have been referencing this repo as a module, to allow users to use different Waveshare displays. To be specific, using it with the October 10th Raspberry Pi OS. It's also not limited to Raspberry Pi 4, it does happen on Raspberry Pi Zero, Zero two, etc.

It would be appreciated if a waveshare team member could give some attention to this issue and implement a more reliable fix on the epdconfig instead, so users don't have to edit a file to get the waveshare code working with latest Raspberry Pi OS. Sorry not sure who that would be @SSYYL @kmanc @waveshareteam ?

Write them via Email, they dont look here very often - but via Email you get near instant answers.

[rjpcasalino]

But if you see epdconfig.py file, sysfs_software_spi.so is only necesary for JetsonNano, no Raspberry Pi, so I dont know why but its geting the wrong system:

@jcolladosp yeah, I don't get that either but was throwing me off for a bit as I thought SPI wasn't active (and it wasn't since I was using NixOS) but switching to Rpi OS (bookworm) also threw this error with SPI enabled and rebooted...so I just commented out the bits (basically your suggestion from above) that were trying to load up the JetsonNano stuff and 🎉 it works like a dream - using an older RPi 3

[gregyone]

Found the missing piece of the puzzle. The python demo now runs for me without issue.

To summarize the changes made:

At line 233 of /home/username/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epdconfig.py I changed /sys/bus/platform/drivers/gpiomem-bcm2835 to /sys/bus/platform/drivers

At line 94 of /home/username/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epd2in13g.py I changed self.send_data(self.Source_BITS/256) to self.send_data(self.Source_BITS//256)

At line 96 of /home/username/e-Paper/RaspberryPi_JetsonNano/python/lib/waveshare_epd/epd2in13g.py I changed self.send_data(self.Gate_BITS/256) to self.send_data(self.Gate_BITS//256)

---

Thanks man, it saves my day !
Greg