Support for rtl8821CU wifi driver

vpeter · 28 August 2022 09:41

This stick should just work without doing anything extra.

If you created file /storage/.config/udev.rules.d/40-modeswitch.rules please remove it

rm /storage/.config/udev.rules.d/40-modeswitch.rules

After that reboot the device and send me dmesg output (url you get!)

dmesg | paste

jez76 · 28 August 2022 20:22

-link removed-

Sorry for the delay, I wasn’t allowed to make anymore posts as I’m a new user

vpeter · 29 August 2022 07:31

Everything looks ok to me and it should work.
Reboot again with stick attached and then run this command and post url.

 journalctl -l | paste

jez76 · 29 August 2022 07:58

link removed

vpeter · 29 August 2022 08:30

I don’t see anything what could be wrong.

As I wrote it should just work.

jez76 · 29 August 2022 08:34

It seems to be currently being detected as a usb storage device as it I think it has the drivers on the stick. Don’t i need to add a command to switch modes so it’s detected as a wifi adapter?

You mentioned earlier I should open file /storage/.config/idea.rules.d/40-modeswitch.rules and edit the file with the product ID and Vendor ID? If you could give me a step-by-step of what commands to type to open and edit /storage/.config/idea.rules.d/40-modeswitch.rules I’d greatly appreciate it. Thanks for all your help so far

vpeter · 29 August 2022 09:37

Files 40-modeswitch.rule is already present with correct VID/PID. SO nothing can be edit manually. I’m not sure why it doesn’t work for you.

github.com

CoreELEC/CoreELEC/blob/coreelec-19/packages/linux/udev.d/40-modeswitch.rules#L15


      
          KERNEL!="sr[0-9]*", GOTO="end_modeswitch"
          SUBSYSTEM!="block", GOTO="end_modeswitch"
          
          # Atheros Wireless / Netgear WNDA3200
          ATTRS{idVendor}=="0cf3", ATTRS{idProduct}=="20ff", RUN+="/usr/bin/eject '/dev/%k'"
          
          # Realtek RTL8821CU chipset 802.11ac NIC
          #   initial cdrom mode 0bda:1a2b, wlan mode 0bda:c811
          # Odroid WiFi Module 5B
          #   initial cdrom mode 0bda:1a2b, wlan mode 0bda:c820
          ATTRS{idVendor}=="0bda", ATTRS{idProduct}=="1a2b", RUN+="/usr/bin/eject '/dev/%k'"
          
          LABEL="end_modeswitch"

You can try changing mode with autostart.sh like described here:

jez76 · 29 August 2022 10:49

Thank you, so I could try adding the following to autostart.sh?

#!/bin/sh

(
usb_modeswitch -KW -v 0bda -p 1a2b
) &

If that’s correct can you please tell me step by step what I type to open the file, edit it and add that to autostart.sh? I don’t know how to open and edit files in ssh

jez76 · 29 August 2022 11:27

Thanks so much for your help so far, I followed these steps from a reddit thread, based on the thread you posted, to change mode with autostart.sh and my wifi adapter now works!!

Thanks again for taking the time to look into my issues

system · 12 September 2022 11:28

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