(Updated 20 Jan 2008–added “sudo ndiswrapper -m” step, and added a note about manual configuration)

As a follow-up to my earlier post on using the Linksys WPC54G v2 with Ubuntu Gutsy, the procedure for using the WUSB54G is quite similar.

First, know that the WUSB54G comes in several versions. You can determine the version by looking on the bottom of the adapter. If you don’t see a version number anywhere, it’s version 1. I have a version 1 and a version 4 adapter, and the instructions for each are similar.

Once again, you’ll need your Ubuntu 7.10 installation CD and the setup CD for your adapter.

Okay, here are the steps.

1) Unplug the adapter from its slot.

2) Install ndiswrapper using the Synaptic Package Manager (it’ll install it from the Ubuntu Live CD, so make sure your CD is in the drive). You can start the Synaptic Package Manager from the main menubar (System/Administration/Synaptic Package Manager). You need to install two packages: ndiswrapper-common and ndiswrapper-utils-1.9 (you can use the Search button in the Synaptic Package Manager to find these–search on “ndis”). (Note: I’ve seen other instructions on the web for getting this adapter to work, and those instructions called for recompiling ndiswrapper from source code. This may have been needed for earlier versions of Ubuntu or ndiswrapper, but doesn’t appear to be needed for 7.10.)

3) Next, we need a place to put the driver files, so create a folder named “Linksys” (or whatever you want) under your home directory. To do this, click Places/Home Folder from the main menubar, and when the File Browser window appears, right-click somewhere in the window and select “Create Folder” from the popup menu that appears, and then type the desired folder name when the new folder appears.

4) Now we’ll copy the driver files from the Linksys installation CD for your adapter. Stick your Linksys installation CD in the drive. The drivers are found in a folder named \Drivers\WUSB54Gv1 for version 1, or \Drivers\WUSB54Gv4 for version 4. Copy all the files from the appropriate folder on the Cd for your adapter version to your newly-created “Linksys” folder:

For version 1 of the adapter, you’ll copy the following files:

WUSB209x.sys
WUSB20XP.sys
WUSB54G.cat
WUSB54G.inf

For version 4 of the adapter, you’ll need these files:

rt2500usb.inf
rt2500usb.sys
WUSB54GV4.cat

5) Install the drivers using ndiswrapper. For version 1, type

sudo ndiswrapper -i WUSB54G.inf

For version 4, type

sudo ndiswrapper -i rt2500usb.inf

6) Now install ndiswrapper as a module. Type

sudo depmod -a
sudo modprobe ndiswrapper

7) Next we need to prevent the native driver for this device from loading. For version 1, type

sudo modprobe -r p54usb

For version 4, type

sudo modprobe -r rt2500usb

Then edit the /etc/modprobe.d/blacklist file:

sudo gedit /etc/modprobe.d/blacklist

and add “blacklist p54usb” (for version 1) or “blacklist rt2500usb” (for version 4) (without the quotes) at the end of the file.

8) Now insert your wireless card. Then type

ndiswrapper -l

You should see output that looks like this for version 1:

wusb54g : driver installed
device (5041:2234) present (alternate driver: p54usb)

or like this, for version 4:

rt2500usb : driver installed
device (13B1:000D) present (alternate driver: rt2500usb)

If so, your card was detected and associated with the correct driver.

9) Now add an alias to associate your wireless network interface to ndiswrapper in /etc/modprobe.d/ndiswrapper. Type

sudo ndiswrapper -m

10) Set ndiswrapper to load automatically. Edit the /etc/modules file:

sudo gedit /etc/modules

and add “ndiswrapper” (without the quotes) at the end of the file.

11) Reboot. After the reboot completes, you should be able to left-click on the Network icon toward the right side of the main menubar and have it display a list of wireless networks. Click the radio button next to the wireless network you’d like to connect to. You’ll be prompted for the network wireless password. Enter it, and you should soon be connected!

Note for version 2 users: I’ll bet you can look at the instructions for versions 1 and 4 and figure out how to modify them for version 2. Note that the name of the alternate driver that shows up in step 8 is the same as the name of the driver that we blacklisted in step 7. In step 4, copy the files from \Drivers\WUSB54Gv2. In step 5, the name of the .inf file is WUSB54GV2.inf.

If you open up the Network Manager and examine the settings for your wireless adapter now, you’ll see that it’s been set to enable roaming mode. This means that your IP address and will by dynamically assigned by the network it connects to. This is fine for most situations, but if you need to assign a static IP address to your PC, you’ll need to disable roaming mode and manually specify the network settings. My experience is that you will also need to undo step 10 above by removing the “ndiswrapper” line from /etc/modules.