Z-World RCM3000, Руководство пользователя

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32 802.11b (Wi-Fi) Add-On Kits
Once the PC or notebook is set up, we're ready to communicate. You can use Telnet or a
Web browser such as Internet Explorer, which come with most Windows installations, to
use the network interface, and you can use Hyperterminal to view the serial port when
these are called for in some of the later sample programs.
Now we’re ready to run the sample programs.
4.4 Sample Programs
WIFI_SCAN.C
WIFI_SCAN.C
illustrates the scan function of the Wi-Fi CompactFlash card to look for
access points or ad-hoc devices. This sample program does not require additonal configu-
ration of the Wi-Fi CompactFlash card, such as setting the IP address or SSID/channel in
order to function, since the Wi-Fi CompactFlash card does not actually join an 802.11b
network.
Once the scan request has been issued, the host RabbitCore or PowerCore module will
read out the scan results and parse the information. The scan results contain information
for each device discovered. This information includes the channel number, the MAC
address, the signal strength of the detected device, and the average noise level as seen by
the device. It also includes the SSID of the device.
The Dynamic C STDIO window will display
Scanning....Completed
, and will display
a list of access points/ad-hoc hosts in your vicinity as in the example shown below.
The following fields are shown in the Dynamic C STDIO window.
•
SSID—the name of the service set access point/ad-hoc host.
•
Channel—the channel assignment that the access point/ad-hoc host is using (00–14).
•
Band—the 802.11 protocol supported by the access point/ad-hoc host.
•
Signal—the signal strength of the access point/ad-hoc host in dBm .
•
Noise—the average noise of the channel.
•
BSSID—the hardware (MAC) address of the BSS responder.
•
Mode—whether the access point/ad-hoc host found is in infrastructure or in ad-hoc
mode.
•
Security—whether the encryption for the access point/ad-hoc host is on or off.
10 log
×
=
power
1 mW
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