Rabbit RabbitCore RCM4400W, Руководство по эксплуатации продукта

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64 RabbitCore RCM4400W
•
PINGLED_WPA_PSK.C
—This program demonstrates the use of WPA PSK (Wi-Fi
Protected Access with Pre-Shared Key). WPA is a more secure replacement for WEP.
The implementation in the sample program supports use of the TKIP (Temporal Key
Integrity Protocol) cypher suite.
The sample program uses macros to configure the access point for WPA PSK, specify
the TKIP cypher suite, assign the access point SSID, and set the passphrase.
#define WIFI_USE_WPA // Bring in WPA support
#define _WIFI_WEP_FLAG WIFICONF_WEP_TKIP // Define cypher suite
#define _WIFI_SSID "parvati"
#define _WIFI_PSK_PASSPHRASE "now is the time"
The next macro specifies 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.
#define _WIFI_PSK_HEX
When you assign your own key, there is a good chance of typos since the key is long. It
is advisable to enter the key in this macro first, then copy and paste into your access
point to ensures that both the RCM4400W and the access point have the same key.
Initially, it may be easier to use the 64 hexadecimal digits form of the key rather than
the ASCII passphrase. A passphrase requires considerable computation effort, which
delays the startup of the sample by about 40 seconds.
If you want to add authentication, set the authentication to “open system,” which basi-
cally means that knowing the key is sufficient to allow access.
#define WIFI_AUTH WIFICONF_AUTH_OPEN_SYS
Change
PING_WHO
to the host you want to ping. You may modify
PING_DELAY
to
change the amount of time in milliseconds between the outgoing pings.
Uncomment the
VERBOSE
define to see the incoming ping replies.
Once you have compiled the sample program and it is running, LED DS2 will flash
when a ping is sent, and LED DS3 will flash when a ping is received.
•
POWERDOWN.C
—This program demonstrates how to power down the FPGA chip in the
Wi-Fi circuit to reduce power consumption. Note that powering down the Wi-Fi portion
of the RCM4400W module results in a loss of the network interface (unlike an Ethernet
connection), and so is only suitable for applications such as data logging where only
intermittent 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.
•
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.