The WIFI-G-USB-2 USB wireless adapter (aka WIFI dongle) provides an "out of the box" solution that enables customers to securely connect their Technologic Systems SBC to a wireless Access Point (AP) or Adhoc network.
In Feburary 2010, the WIFI-G-USB dongle (IO Gear GWU523) was replaced with the new WIFI-G-USB-2 dongle (Asus WL-167g) for two reasons: 1.) the WIFI-G-USB dongle had a severe driver bug which caused any product running the 2.4 kernel to hang in the mere presence of a wireless N network and 2.) IO Gear announced EOL for that product. Major differences in these two dongles that customers need to be aware of include different dimensions and wireless chipsets as outlined below:
Dimensions:
IOGear: 6.0 cm L* 2.5 cm W* 1.0 cm H
Asus: 7.5 cm L* 2.5 cm W* 0.9 cm H
Chipset:
IOGear: Zydas1211
Asus: rt2501usb
Other areas of interest of differences between the two devices include (specs taken from manufactures product page):
Temp Range:
IOGear: 0 - 55C
Asus: -10 - 55C
RF Output Power:
IOGear: 17 dBm
Asus: 14 ~ 17 dBm (at nominal temp. range)
Antennae Option:
IOGear: None
Asus: One onboard Inverted-F antenna to support diversity (Gain: 1.77dBi)
Range:
IOGear: 100 - 400m, depending on surrounding environment
Asus: Indoor 130 ft (40 m), outdoor (LOS, Line-Of-Sight) 1000 ft (330 m)
Accessories:
IOGear: None
Asus: USB 2.0 Universal Joint
USB 2.0 extension cable (type A to type A)
Neck lace
In our field tests, the range of the WIFI-G-USB-2 outperformed WIFI-G-USB by about 80ft. Additionally, the WIFI-G-USB-2 dongle supports an external antennae for further range.
The WIFI-G-USB-2 dongle uses the Ralink RT2501USB(RT73:RT2571W/RT2573/RT2671) chipset and requires the rt73 driver. For WPA and WPA2 connections, it requires the wpa_supplicant utility which has been compiled with Ralink sources. These files have already been compiled for all TS products and can be obtained here:
This section gives step by step instructions for how to connect to wireless Access Points (AP) using the rt73 driver and RT2501USB chipset. It was tested using a Linksys WRT54GC Wireless Router as an AP. Master mode is not supported by this driver, but Adhoc is. As a note, WPA is generally disabled by default on startup, but can be enabled (see /etc/init.d/wpasupplicant).
The first step should be to locate the appropriate driver for the TS product
in use, download it to the board, and then use the insmod command
(ie. insmod rt73_tsXXXX.ko). When inserted properly, you will see
the device in /proc/net/wireless. Use cat /proc/net/wireless
to verify:
root@ts7000:root# cat /proc/net/wireless
Inter-| sta-| Quality | Discarded packets | Missed | WE
face | tus | link level noise | nwid crypt frag retry misc | beacon | 16
rausb0: 0000 100. 220 177 0 0 0 0 0 0
Wireless connections tested:
Useful Commands:
iwconfig -- use to check status such as associationsiwlist scan -- reports wireless networks availablepump OR dhclient OR udhcpc -- assign a dynamic IP address
1) Bring the rausb0 interface up
* ifconfig rausb0 up
2) Associate with the AP
* iwconfig rausb0 essid the_essid
3) Assign a static IP
* ifconfig rausb0 192.168.1.101
1) Bring the rausb0 interface up
* ifconfig rausb0 up
2) Associate with AP
* iwconfig rausb0 essid the_essid key the_key
3) Assign a static IP
* ifconfig rausb0 192.168.1.101
1) Bring the rausb0 interface up
* ifconfig rausb0 up
2) Generate a configuration file for wpa_supplicant to use
* ./wpa_passphrase the_essid the_password > /etc/wpa_supplicant_custom.conf
3) Use wpa_supplicant to associate with AP and run it in the background (-B)
* ./wpa_supplicant -irausb0 -Dralink -c/etc/wpa_supplicant_custom.conf -B
4) Assign a static IP
* ifconfig rausb0 192.168.1.101
1) Bring the rausb0 interface up
* ifconfig rausb0 up
2) Generate a configuration file for wpa_supplicant to use
* ./wpa_passphrase the_essid the_password > /etc/wpa_supplicant_custom.conf
3) Insert "proto=RSN" into "network" block in /etc/wpa_supplicant_custom.conf
4) Use wpa_supplicant to associate with AP and run it in the background (-B)
* ./wpa_supplicant -irausb0 -Dralink -c/etc/wpa_supplicant_custom.conf -B
5) Assign a static IP
* ifconfig rausb0 192.168.1.101
1) Bring the rausb0 interface up
* ifconfig rausb0 up
2) Setup rausb0 for Adhoc mode
* iwconfig rausb0 mode ad-hoc channel 3 enc off essid the_essid
3) Assign a static IP
* ifconfig 169.254.114.101 netmask 255.255.0.0
4) Add default gateway to route (optional)
* route add default gw 169.254.114.100
| Date of Issue/Revision | Revision Number | Comments |
|---|---|---|
| 02/23/2010 | 1.0 | Created as "WIFI-G-USB-2 Manual" |
| 02/26/2010 | 1.1 | Added section "Adhoc Mode" |
| 03/04/2010 | 1.2 | Made some minor clarification changes Fixed header section numbers |
| 03/15/2010 | 1.3 | Removed date from filenames and links on FTP site |
If you are having difficulties in pinging your AP, try to disconnect eth0 by
using the command ifconfig eth0 down.
If you have a TS-75XX or newer series of boards with the rt2x00 open source
driver compiled in the kernel, it is suggested that the rt73usb module be
blacklisted by including the line blacklist rt73usb in the
/etc/modprobe.d/blacklist file, otherwise you may experience stability
issues.
The message ioctl[SIOCGIWAP]: Transport endpoint is not connected
can be safely ignored.
The message rt73: Unknown symbol x means that the module
dependencies have not been satisfied. Use the following as a guide as a basic
checklist to insure the correct modules are loaded:
ts7000:~# depmod ts7000:~# modprobe hid ts7000:~# modprobe usbcore ts7000:~# modprobe usb_storage ts7000:~# modprobe scsi_mod ts7000:~# modprobe ohci_hcd
The message insmod: error inserting 'rt73_tsXXXX.ko': -1 Invalid module format
will occur if you are trying to insert a module into a kernel that it was not
compiled for. Verify that you have the correct module for your board. If
you're sure the module should work, try using the insmod command
with the -f option (ie. insmod -f rt73_tsXXXX.ko).