Help getting Cudy WP650 (rtl8821cu) working (SOLVED)

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shryke300
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Help getting Cudy WP650 (rtl8821cu) working (SOLVED)

Post by shryke300 »

NOTE: The original problem is not solved, but I do have WiFi now, which was the goal! If you are working on the USB, I hope one of the posts will help you. I "un-hardblocked" my internal card to get it to work.

Hi, I have Linux Mint 20 (Cinnamon) on my laptop. I'm trying to get my Wi-Fi to work. I originally wanted to use the laptop's wireless, but read somewhere it wasn't supported. So I purchased a wireless USB that (from google searches and product description) would work with Linux. So far, I have tried to follow the installation guide that came with it and got the kernel installed (I think), and tried half a dozen other installation methods I found on this forum and on this site: https://easylinuxtipsproject.blogspot.c ... t.html#ID4 . None of them have worked to get the Wi-Fi working. With the installation guide that came with it, it seems like I got through everything until

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sudo usb_modeswitch -KW -v 0bda -p c811 
. It starts to compile, then I get the message below:

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Take all parameters from the command line


 * usb_modeswitch: handle USB devices with multiple modes
 * Version 2.5.2 (C) Josua Dietze 2017
 * Based on libusb1/libusbx

 ! PLEASE REPORT NEW CONFIGURATIONS !

DefaultVendor=  0x0bda
DefaultProduct= 0xc811

StandardEject=1

Look for default devices ...
  found USB ID 04f2:b446
  found USB ID 0bda:c811
   vendor ID matched
   product ID matched
  found USB ID 8087:8000
  found USB ID 1d6b:0002
  found USB ID 1d6b:0003
  found USB ID 1d6b:0002
 Found devices in default mode (1)
Access device 003 on bus 001
Get the current device configuration ...
Current configuration number is 1
Use interface number 0
 with class 255
Error: can't use storage command in MessageContent with interface 0; interface class is 255, expected 8. Abort
I just want to get the Wi-Fi working. I am VERY new to Linux and am learning as I go through it. If someone can help me sort this, I will be very grateful! I don't mind if the internal Wi-Fi can work, either... I have also tried using the Wi-Fi button on the keyboard to make sure it wasn't an issue there, either. I will post the instructions that came with the USB device, below, as well as the info requested in the forum READ ME section.

Instructions that came with the USB:

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# Realtek RTL8811CU/RTL8821CU USB wifi adapter driver version 5.4.1 for Linux 4.4.x up to 5.3.x

Before build this driver make sure `make`, `gcc`, `linux-header` and `git` have been installed.

## First, clone this repository
```
mkdir -p ~/build
cd ~/build
git clone https://github.com/brektrou/rtl8821CU.git
```
## Build and install with DKMS

DKMS is a system which will automatically recompile and install a kernel module when a new kernel gets installed or updated. To make use of DKMS, install the dkms package.

### Debian/Ubuntu:
```
sudo apt-get install dkms
```
### Arch Linux/Manjaro:
```
sudo pacman -S dkms
```
To make use of the **DKMS** feature with this project, just run:
```
./dkms-install.sh
```
If you later on want to remove it, run:
```
./dkms-remove.sh
```

### Plug your USB-wifi-adapter into your PC
If wifi can be detected, congratulations.
If not, maybe you need to switch your device usb mode by the following steps in terminal:
1. find your usb-wifi-adapter device ID, like "0bda:1a2b", by type:
```
lsusb
```
2. switch the mode by type: (the device ID must be yours.)

Need install `usb_modeswitch` (Archlinux: `sudo pacman -S usb_modeswitch`)
```
sudo usb_modeswitch -KW -v 0bda -p 1a2b
```

It should work.

## Build and install without DKMS
Use following commands:
```
cd ~/build/rtl8821CU
make
sudo make install
```
If you later on want to remove it, do the following:
```
cd ~/build/rtl8821CU
sudo make uninstall
```
## Checking installed driver
If you successfully install the driver, the driver is installed on `/lib/modules/<linux version>/kernel/drivers/net/wireless/realtek/rtl8821cu`. Check the driver with the `ls` command:
```
ls /lib/modules/$(uname -r)/kernel/drivers/net/wireless/realtek/rtl8821cu
```
Make sure `8821cu.ko` file present on that directory

### Check with **DKMS** (if installing via **DKMS**):

``
sudo dkms status
``
Some Miscellaneous info:

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my computer:~$ rfkill list all
0: phy1: Wireless LAN
	Soft blocked: no
	Hard blocked: yes
my computer:~$ iwconfig
enp3s0    no wireless extensions.

wlp4s0    IEEE 802.11  ESSID:off/any  
          Mode:Managed  Access Point: Not-Associated   Tx-Power=off   
          Retry short limit:7   RTS thr:off   Fragment thr:off
          Power Management:off
          
lo        no wireless extensions.
Here is the "inxi" command data:

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System:
  Kernel: 5.4.0-52-generic x86_64 bits: 64 compiler: gcc v: 9.3.0 
  Desktop: Cinnamon 4.6.7 wm: muffin 4.6.3 dm: LightDM 1.30.0 
  Distro: Linux Mint 20 Ulyana base: Ubuntu 20.04 focal 
Machine:
  Type: Laptop System: TOSHIBA product: Satellite C55-B v: PSCLUU-00X00D 
  serial: <filter> Chassis: type: 10 v: * serial: <filter> 
  Mobo: TOSHIBA model: ZSWAA v: 1.00 serial: <filter> UEFI: TOSHIBA v: 1.20 
  date: 04/11/2014 
Battery:
  ID-1: BAT1 charge: 9.6 Wh condition: 9.6/45.0 Wh (21%) volts: 15.3/15.0 
  model: TOSHIBA PABAS0241231 type: Li-ion serial: <filter> status: Full 
CPU:
  Topology: Dual Core model: Intel Core i3-4005U bits: 64 type: MT MCP 
  arch: Haswell rev: 1 L2 cache: 3072 KiB 
  flags: avx avx2 lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx 
  bogomips: 13568 
  Speed: 798 MHz min/max: 800/1700 MHz Core speeds (MHz): 1: 798 2: 798 
  3: 798 4: 801 
Graphics:
  Device-1: Intel Haswell-ULT Integrated Graphics vendor: Toshiba 
  driver: i915 v: kernel bus ID: 00:02.0 chip ID: 8086:0a16 
  Display: x11 server: X.Org 1.20.8 driver: modesetting unloaded: fbdev,vesa 
  resolution: 1366x768~60Hz 
  OpenGL: renderer: Mesa DRI Intel HD Graphics 4400 (HSW GT2) 
  v: 4.5 Mesa 20.0.8 compat-v: 3.0 direct render: Yes 
Audio:
  Device-1: Intel Haswell-ULT HD Audio driver: snd_hda_intel v: kernel 
  bus ID: 00:03.0 chip ID: 8086:0a0c 
  Device-2: Intel 8 Series HD Audio vendor: Toshiba driver: snd_hda_intel 
  v: kernel bus ID: 00:1b.0 chip ID: 8086:9c20 
  Sound Server: ALSA v: k5.4.0-52-generic 
Network:
  Device-1: Realtek RTL810xE PCI Express Fast Ethernet vendor: Toshiba 
  driver: r8169 v: kernel port: d000 bus ID: 03:00.0 chip ID: 10ec:8136 
  IF: enp3s0 state: up speed: 100 Mbps duplex: full mac: <filter> 
  Device-2: Qualcomm Atheros AR9485 Wireless Network Adapter vendor: Lite-On 
  driver: ath9k v: kernel port: d000 bus ID: 04:00.0 chip ID: 168c:0032 
  IF: wlp4s0 state: down mac: <filter> 
Drives:
  Local Storage: total: 698.64 GiB used: 50.80 GiB (7.3%) 
  ID-1: /dev/sda vendor: HGST (Hitachi) model: HTS541075A9E680 
  size: 698.64 GiB speed: 3.0 Gb/s rotation: 5400 rpm serial: <filter> 
  rev: A700 scheme: GPT 
Partition:
  ID-1: / size: 686.18 GiB used: 25.39 GiB (3.7%) fs: ext4 dev: /dev/sda2 
Sensors:
  System Temperatures: cpu: 46.0 C mobo: N/A 
  Fan Speeds (RPM): N/A 
Repos:
  No active apt repos in: /etc/apt/sources.list 
  Active apt repos in: /etc/apt/sources.list.d/official-package-repositories.list 
  1: deb http://packages.linuxmint.com ulyana main upstream import backport #id:linuxmint_main
  2: deb http://archive.ubuntu.com/ubuntu focal main restricted universe multiverse
  3: deb http://archive.ubuntu.com/ubuntu focal-updates main restricted universe multiverse
  4: deb http://archive.ubuntu.com/ubuntu focal-backports main restricted universe multiverse
  5: deb http://security.ubuntu.com/ubuntu/ focal-security main restricted universe multiverse
  6: deb http://archive.canonical.com/ubuntu/ focal partner
Info:
  Processes: 198 Uptime: 15h 15m Memory: 5.72 GiB used: 3.20 GiB (55.9%) 
  Init: systemd v: 245 runlevel: 5 Compilers: gcc: 9.3.0 alt: 9 Shell: bash 
  v: 5.0.17 running in: gnome-terminal inxi: 3.0.38 

Long story short, please help me figure out why I can't get my Wi-Fi to work.
Last edited by shryke300 on Mon Nov 09, 2020 1:50 pm, edited 1 time in total.
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karlchen
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Location: Germany

Re: Help getting Cudy WP650 (rtl8821cu) working

Post by karlchen »

Hello, shryke300.
I'm trying to get my Wi-Fi to work. I originally wanted to use the laptop's wireless, but read somewhere it wasn't supported.
So have you ever tried to use your internal wifi adapter?

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my computer:~$ rfkill list all
0: phy1: Wireless LAN
	Soft blocked: no
	Hard blocked: yes
This looks as if you hard-blocked your internal wifi adapter.
Either it has been switched of in the Bios.
Or the machine has got a hardware wifi switch, which has been used to switch the adapter off.

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Network:
  Device-2: Qualcomm Atheros AR9485 Wireless Network Adapter vendor: Lite-On 
  driver: ath9k v: kernel port: d000 bus ID: 04:00.0 chip ID: 168c:0032 
  IF: wlp4s0 state: down mac: <filter> 
Looks as if this wifi adapter might be functional, after it has been switched on again.

Any reason why the internal wifi has been switched off and why you are trying to use the external USB adapter instead?
The USB adapter is not found anywhere in your inxi report. The internal adapter, however, is found; the loaded driver is ath9k. Might work after switching the adapter back on.

Karl
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sleeper12
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Joined: Thu May 25, 2017 3:22 pm

Re: Help getting Cudy WP650 (rtl8821cu) working

Post by sleeper12 »

Karl is right, your internal card should work if you turn wifi back on. Maybe Fn & F12?
sleeper12
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Posts: 10057
Joined: Thu May 25, 2017 3:22 pm

Re: Help getting Cudy WP650 (rtl8821cu) working

Post by sleeper12 »

If you want to get the usb adapter working, try one line at a time:

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sudo apt install build-essential -y
mkdir -p ~/build
cd ~/build
sudo apt install git
git clone https://github.com/brektrou/rtl8821CU.git
cd rtl8821CU
make
sudo make install 
Reboot
shryke300
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Re: Help getting Cudy WP650 (rtl8821cu) working

Post by shryke300 »

Thank you for all the replies. I will call this tentatively solved. I believe I fixed it through the BIOS menu. I'm not sure how I missed it before, but I am very new to this. SO... the USB is not working (i have not tried the most recent suggestion yet), but the internal card is, so I am happy! Thank you for the help and the patience for someone trying to learn more!
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