Rabbit RabbitCore RCM5400W, Руководство пользователя, Страница: 76 / 120

70 RabbitCore RCM5400W
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PINGLED_WPA2_CCMP.C
—This sample program is an extension of
PINGLED.C
. It
demonstrates the use of WPA2 PSK (Wi-Fi Protected Access with Pre-Shared Key).).
WPA is a more secure replacement for WEP. The implementation in the sample pro-
gram uses the Advanced Encryption Standard (AES) based algorithm, also known as
the CCMP (Counter Mode with Cipher Block Chaining Message Authentication Code
Protocol) cypher suite.
Apart from the configuration of
WPA2_CCMP
at the top of the sample program, the rest
of the code is identical to the case without WPA2 PSK. Indeed, most of the TCP/IP
sample programs should work with WPA2 CCMP simply by using the same configura-
tion settings.
Configure your access point for WPA2 PSK before you run this sample program.
Specify the CCMP cypher suite, and enter a suitable pre-shared key. The key may be
entered either as 64 hexadecimal digits or as an ASCII string of up to 63 characters.
TIP: There is a good chance of typos since the key is long. First, enter the key in this
sample program macro, then copy and paste it to your access point. This ensures that
both the RCM5400W and the access point have the same key.
TIP: For an initial test, it may be easier to use the 64 hex digit form of the key rather than
the ASCII passphrase. A passphrase requires considerable computation effort, which
delays the startup of the sample program by about 30 seconds.
Now change
PING_WHO
to the address of the host you want to ping.
You may modify the
PING_DELAY
define to change the amount of time (in milliseconds)
between the outgoing pings.
Uncomment the VERBOSE define to see the incoming ping replies.
Finally, compile and run this sample program. LED DS2 will flash when a ping is sent.
LED DS3 will flash when a ping is received.
•
POWERDOWN.C
—This program demonstrates how to power down the radio transmitter
(U18) to reduce power consumption. Note that powering down the Wi-Fi portion of the
RCM5400W module results in a loss of the network interface (unlike an Ethernet con-
nection), and so is only suitable for applications such as data logging where only inter-
mittent network connectivity is required.
The sample program demonstrates the powerdown operation as a simple sequential
state machine. LED DS2 on the Prototyping Board will be on when the network inter-
face is up, and LED DS3 will be on when the Wi-Fi circuit is powered up.
Before you compile and run this sample program, modify the configuration macros,
including the
DOWNTIME
and the
UPTIME
values. The interface will be powered up and
down for these intervals.
Now set up a continuous ping on another host, and observe the pings time out succes-
sively, then succeed, depending on the LED state.
•
SMTP.C
—This program demonstrates using the SMTP library to send an e-mail when
the S2 and S3 switches on the Prototyping Board are pressed. LEDs DS2 and DS3 on
the Prototyping Board will light up when e-mail is being sent.