Wireless Dongle RTL8188CUS

[leeqicheng]

Hi i just bought this model of dongle RTL8188CUS but met with a few questions

First
When i plug in to the rpi it kinda of restart my rpi is this normal ?

Second is there any detail guide as of how to install the driver (RTL8188CUS)

third is there any guide on making an auto connection string on wpa2 Enterprise using username and password to login to router rather secretPass

thanks

[fruitoftheloom]

The RTL8188CUS is supported, no extra drivers required.

The WiFi Dongle should be plugged in before powering up the Pi

Ensure you have a decent Power Supply 5v 1A is minimum advisable, but checking TP1 TP2 voltage if have power issues as not all Power Supplies are are made equal

http://elinux.org/R-Pi_Troubleshooting# ... r_problems

Generally I advise to use a Mains Powered USB Hub for USB Peripherals !

[MrEngman]

If you plug a wifi dongle into the Pi while it is powered on and running it will almost certainly cause it to reset and could cause your SD card to become corrupted. You should plug your dongle in to the Pi before applying power.

There is loads of stuff about rtl8188cus dongles in the forum, like the Edimax EW-7811UN which is one of the favourites.

You don't need to install the driver it should already be installed. It is just a matter of configuring the necessary files to connect to the network you want to connect to and that is pretty much the same for any wifi dongle. There's some basic stuff here.

I think there have been people talking about wpa2 enterprise connecting with username and password but you will need to search for it.

The forum built in search is pretty awful. One of the better ways is to use google with "site:raspberrypi.org your-search-term".


MrEngman

[leeqicheng]

But current it detect my RTL8188CUS but i tried using wifi-config to scan for any network but it return null isit got to do with the config file ?

If you plug a wifi dongle into the Pi while it is powered on and running it will almost certainly cause it to reset and could cause your SD card to become corrupted. You should plug your dongle in to the Pi before applying power.

There is loads of stuff about rtl8188cus dongles in the forum, like the Edimax EW-7811UN which is one of the favourites.

You don't need to install the driver it should already be installed. It is just a matter of configuring the necessary files to connect to the network you want to connect to and that is pretty much the same for any wifi connection. There's some basic stuff here.

I think there have been people talking about wpa2 enterprise connecting with username and password but you will need to search for it.

The forum built in search is pretty awful. One of the better ways is to use google with "site:raspberrypi.org your-search-term".


MrEngman

[MrEngman]

But current it detect my RTL8188CUS but i tried using wifi-config to scan for any network but it return null isit got to do with the config file ?

This can happen if you have made any changes to the config files, /etc/network/interfaces or /etc/wpa_supplicant/wpa_supplicant.conf that Wifi Config does not like.

Also if you are running the GUI (Graphical User Interface) and using the Wifi Config it will likely be using maximum power and this problem, not seeing a list of networks, could be caused by an inadequate power supply.

You could try closing the GUI and running from the command line interface. You can scan for wifi networks using the command

Code: Select all

sudo iwlist wlan0 scan

and see if this shows a list of networks.

It could help determine what is happening if you can you supply the data from the following commands

Code: Select all

cat /etc/network/interfaces
sudo cat /etc/wpa_supplicant/wpa_supplicant.conf
ifconfig

and please make sure you remove any passwords they may show.



MrEngman

[leeqicheng]

Update i just reformated my RPI clean

so what i did was update kernal and update all updates

reboot and plug in the Wireless dongle and i scan but still no result it could be the power but i not sure could anyone confirm this

But current it detect my RTL8188CUS but i tried using wifi-config to scan for any network but it return null isit got to do with the config file ?

This can happen if you have made any changes to the config files, /etc/network/interfaces or /etc/wpa_supplicant/wpa_supplicant.conf that Wifi Config does not like.

Also if you are running the GUI (Graphical User Interface) and using the Wifi Config it will likely be using maximum power and this problem, not seeing a list of networks, could be caused by an inadequate power supply.

You could try closing the GUI and running from the command line interface. You can scan for wifi networks using the command

Code: Select all

sudo iwlist wlan0 scan

and see if this shows a list of networks.

It could help determine what is happening if you can you supply the data from the following commands

Code: Select all

cat /etc/network/interfaces
sudo cat /etc/wpa_supplicant/wpa_supplicant.conf
ifconfig

and please make sure you remove any passwords they may show.



MrEngman

[MrEngman]

Perhaps if you supplied some information on your setup someone might be able to help.

What operating system are you using? What is the output from command

Code: Select all

uname -a

The output from the following commands would help

Code: Select all

cat /etc/network/interfaces
sudo cat /etc/wpa_supplicant/wpa_supplicant.conf
ifconfig

Also what do you get when you use command

Code: Select all

sudo iwlist wlan0 scan

MrEngman

[leeqicheng]

As requested





Thanks for helping really appreciated

Perhaps if you supplied some information on your setup someone might be able to help.

What operating system are you using? What is the output from command

Code: Select all

uname -a

The output from the following commands would help

Code: Select all

cat /etc/network/interfaces
sudo cat /etc/wpa_supplicant/wpa_supplicant.conf
ifconfig

Also what do you get when you use command

Code: Select all

sudo iwlist wlan0 scan

MrEngman

[MrEngman]

Hi leeqicheng,

I have set up one of my Pi with the same settings for /etc/network/interfaces and /etc/wpa_supplicant/wpa_supplicant.conf that you are using and I have no problems scanning for networks using the command sudo iwlist wlan0 scan.

Wifi set up can get very annoying sometimes and I have had problems with wifi scanning and connecting sometimes, but not very often.

One solution I have found that worked for me is power off the Pi and remove the wifi dongle, then power on the Pi without the wifi and boot up and then shutdown the Pi and turn off the power. Then plug the wifi back in the Pi, power on and reboot. I have then found the wifi will usually work. Why it works I an not sure why but it has, for me anyway.

One question. What are the other USB devices you use? Do you have a USB hub? If you have a hub try with the wifi dongle plugged into the hub.


MrEngman

[leeqicheng]

Currently there is no usb connected to it except for the dongle

Could it be take a look at the image beside the Nickname is unassociated , could it be faulty ?

Hi leeqicheng,

I have set up one of my Pi with the same settings for /etc/network/interfaces and /etc/wpa_supplicant/wpa_supplicant.conf that you are using and I have no problems scanning for networks using the command sudo iwlist wlan0 scan.

Wifi set up can get very annoying sometimes and I have had problems with wifi scanning and connecting sometimes, but not very often.

One solution I have found that worked for me is power off the Pi and remove the wifi dongle, then power on the Pi without the wifi and boot up and then shutdown the Pi and turn off the power. Then plug the wifi back in the Pi, power on and reboot. I have then found the wifi will usually work. Why it works I an not sure why but it has, for me anyway.

One question. What are the other USB devices you use? Do you have a USB hub? If you have a hub try with the wifi dongle plugged into the hub.


MrEngman

[MrEngman]

There is no problem with the output from iwconfig that you posted. This is what you will get for a wifi that is not connected to the network. I see the exact same output if my wifi is not connected to the network.

I do not expect the wifi dongle to be faulty but if you want to check it if you have a Windows machine plug it into that and see what happens.

Actually that reminds me of an odd problem I had quite a long time ago. I had a wifi that would not scan or connect, also an rtl8188cus device, so I plugged it into my Windows laptop to check it was OK. It connected to the network and worked OK. I then plugged it back into the Pi and it immediately started to work with the Pi. Why it suddenly started to work with the Pi I'm not sure but it is possible the firmware loaded by the Pi may have been corrupted or something like that and plugging it into the Windows machine reset it and cleaned up the wifi dongle set up.

In your original post you asked about connecting to a WPA2 Enterprise network with login name and password. I'm not sure how to do this,so do you have any other network you can connect to that is not Enterprise? It would make checking the wifi a little easier.

There are some posts on the forum about connecting to enterprise networks and it looks like /etc/wpa_supplicant/wpa_supplicant.conf needs setting something like

Code: Select all

ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1

network={
	ssid="example"
	identity="user@example.com"
	password="foobar"
}

Most examples show additional lines in the file but they may not be require as connecting to a normal WPA2 network can be done with the file like this

Code: Select all

ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1

network={
	ssid="network-name"
	psk="network-password"
}

again with all the additional lines removed. I can connect to my networks using this format.

First, however, you need to get your wifi to scan. It should do with the files you have at the moment so I would suggest if you do have a Windows machine you can try the wifi in that machine to make sure it does work and then put it back in your Pi and then see how it behaves.


MrEngman