RTL8192CU USB (mine is) 0bda:8178 Reaktek WEP WPA WPA2
This Info is for Windows 7 Only. I have no clue if it will work with Windows 8 and I am completely clueless on Linux. I suggest reading through everything first before you start changing anything.
Ok you might be able to do it with the Realtek USB adapter on Windows 7. First you should undo any changes you made when you attempted to get it working prior. You should get your network connections down to just your onboard connection.
Download the realtek driver+utility from the realtek website. (Utility and Driver Auto Installation Program version 1021.3.0912.2012) Install from that without having your usb adapter plugged in. There is a chance that the install hangs on installing Cisco EAP-Fast. If that happens force close the installer then use the 3 installers in the EAP folder that came with the drivers.
Once that is done you should have a realtek wifi utility running in the task bar. (Blue crab looking thing) Insert your wifi adapter then click the crab to open the utility. At this point the utility+adapter will be scanning for wifi hotspots, which is fine. Make sure there is a drop down option listed as Mode, and that you can switch to AP(Access Point) mode. If you are unable to switch it to access point mode, then sadly you won't be able to this method.
Open up your Network connections and you should only see your onboard network connection and the wifi adapter. Rename your wifi connection to "Wi-Fi". Select both and right click them and you should see the option of "Bridge Connections", select it and let windows bridge them. You'll get a new connection called Network Bridge. (If you have a static ip for your computer setup, you will have to add those settings to the network bridge.)
Go back to the realtek wifi utility and switch it to access point mode. Once it finally switches over click config and set your SSID and make sure the 2 drop downs are set to "Open System" and "Disabled". This will make the adapter work as an unprotected wifi access point.
Next we need a program to switch MAC Addresses. The program I have been using is called
MACPass which was made by someone here on GBATemp. If you named your wifi network connection to something other than Wi-Fi you will have to change a setting in the config.ini file within the MACPass folder before you start.
At this point you should have your wifi adapter broadcasting thanks to the realtek wifi utility, and it should be bridged to your onboard connection allowing for internet access. You should test first by making sure your computer has internet, then checking via your 3ds after confirming your computer has access. If you have no other wifi access in your home, you can just check via the browser. If you have your 3ds already setup for your main wifi connection, you can just edit the wifi connections in your 3ds by adding 1 letter to the ssid. This will stop your 3ds from seeing your home wifi and force it use the new open wifi connection from the realtek. The realtek utility will also show when someone is connected to the adapter by listing the device's mac address. Once you know your 3ds mac address, it will make it easier to keep track of anyone else connecting to the open wifi connection.
If everything is working and you can connect to the internet via your 3ds, then it is time for you to start up MACPass. MACPass comes with some default mac addresses that will randomize when you first launch the program. You can add your own MAC's via macs.txt file but you have to keep in mind that Windows will only allow you to change MAC addresses based around "x2, x6, xA, or xE" for the first octet. In the MACPass program uncheck Virtual Miniport if it is checked, then change your delay to 70. (The extra delay is an attempt to adjust for the extra time it takes for the realtek utility to restart and begin broadcasting.) Now click start and the wifi connection and realtek utility should restart itself. I suggest having the utility open so you can keep an eye on it.
Providing everything is working correctly, your 3ds should eventually find the hotspot and begin to streetpass. If you do not notice your 3ds mac address connecting to the hotspot via the realtek utility, save/pause macpass before it automatically changes to the next MAC. If you see your 3ds connect to the hotspot, but do not get a streetpass try another MAC. I have noticed that sometimes I just do not get streetpasses from certain MAC Addresses, I do not know the reason behind it. I know that sometimes I will not get any if my plaza is full, so I will check my 3ds notifications every couple of MAC addresses to see if I am full and need to clear out.
This method requires you to babysit the programs sadly, as the realtek utility will crash sometimes and stop broadcasting. Also every so often MACPass itself will freeze and close. Very rarely will the programs look to be working, but the wifi adapter will be "disconnected" according to windows. When this happens I pause MACPass then disable/re-enable the wifi adapter until its listed as "connected". When you do not wish to use homepass, you just have to disable the wifi connection (Do Not Disable Network Bridge). Even with the wifi disabled and the adapter removed from the computer, you will still have internet access on the computer. Although windows likes to forget the network bridge settings upon reboot if you use a static ip.
