sparkfun MG2639 Cellular Shield, Руководство по подключению

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const char sparkfunDomain[] = "sparkfun.com"; // Domain we wan
t to look up
IPAddress sparkfunIP; // IPAddress variable where we'll store
the domain's IP
gprs.hostByName(sparkfunDomain, &sparkfunIP);
Serial.print("sparkfun.com's IP address is: ");
Serial.println(sparkfunIP);
hostByName()
returns an error code as well. It’ll be a positive number if the
lookup was successful, and a negative number if there was an error or
timeout.
Connecting
To connect to a remote IP address, use either
gprs.connect(IPAddress ip, unsigned int port)
or
gprs.connect(const char * domain, unsigned int port)
to connect to
an IP address or domain string.
For example, to connect to SparkFun on port 80 (the good, old, HTTP port),
send this:
const char sparkFunDomain[] = "sparkfun.com";
int connectStatus;
connectStatus
= gprs.connect(sparkFunDomain, 80);
if (connectStatus > 0)
Serial.println("Connected to SparkFun, port 80");
else if (connectStatus == ­ 1)
Serial.println("Timed out trying to connect to SparkFu
n.");
else if (connectStatus
== ­ 2)
Serial.println("Received an error trying to connect.");
Sending and Receiving
As with other stream classes,
print()
,
write()
,
available()
, and
read()
functions are defined for
gprs
. You can use
print()
to send just
about any, defined variable type in Arduino to a connected server.
Each
print()
takes a long-ish time to execute (about 1-2 seconds), so if
speed is a factor we recommend using as few separate
print()
calls as
possible. For example, these blocks of code do the same thing:
// You can do this to send a GET string..
gprs.println("GET / HTTP/1.1");
gprs.print("Host: ");
gprs.print(server);
gprs.println();
gprs.println();
// But this one is faster:
gprs.print("GET / HTTP/1.1\nHost: example.com\n\n");
But the latter finishes about 8 seconds faster.
To check for data coming from a connected server, back to the MG2639,
use
gprs.available()
and
gprs.read()
.
gprs.available()
returns the
number of bytes currently stored in the library’s receive buffer. If it’s greater
than 0, there’s at least one character there – use
gprs.read()
to read the
first available character in the buffer.
As an example from the sketch:
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