Hi there,
I have an Arduino Uno w. Ethernet Shield running a slightly modified version of the demo WebClient sketch. I am wanting to connect to a server running locally on my macbook (running Mountain Lion), which is what I am also connecting the ethernet cable to. I have been able to connect to the server using it's local IP address (The code below is what I have used to do this), which would be going through my home router. However, I would like to be able to connect to this server without any network connection at all (for easy demonstration purposes).
Note that I am using DHCP, but I don't require this. Although I can't seem to get DHCP working unless I have a network connection.
My feeling is I'll have to set up some kind of virtual gateway, but at this stage am a bit lost. I would appreciate a bit of direction.
/*
Web client
This sketch connects to a website (http://www.google.com)
using an Arduino Wiznet Ethernet shield.
Circuit:
* Ethernet shield attached to pins 10, 11, 12, 13
created 18 Dec 2009
modified 9 Apr 2012
by David A. Mellis
*/
#include <SPI.h>
#include <Ethernet.h>
// Enter a MAC address for your controller below.
// Newer Ethernet shields have a MAC address printed on a sticker on the shield
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
IPAddress server(192,168,0,3); // Google
// Initialize the Ethernet client library
// with the IP address and port of the server
// that you want to connect to (port 80 is default for HTTP):
EthernetClient client;
void setup() {
// Open serial communications and wait for port to open:
Serial.begin(9600);
while (!Serial) {
; // wait for serial port to connect. Needed for Leonardo only
}
// start the Ethernet connection:
Serial.println("Setting up Ethernet");
if (Ethernet.begin(mac) == 0) {
Serial.println("Failed to configure Ethernet using DHCP");
// no point in carrying on, so do nothing forevermore:
for(;;)
;
}
Serial.println("Success!");
// give the Ethernet shield a second to initialize:
delay(1000);
Serial.println("connecting...");
// if you get a connection, report back via serial:
if (client.connect(server, 5000)) {
Serial.println("connected");
// Make a HTTP request:
client.println("GET /home HTTP/1.0");
client.println();
}
else {
// kf you didn't get a connection to the server:
Serial.println("connection failed");
}
}
void loop()
{
// if there are incoming bytes available
// from the server, read them and print them:
if (client.available()) {
char c = client.read();
Serial.print(c);
}
// if the server's disconnected, stop the client:
if (!client.connected()) {
Serial.println();
Serial.println("disconnecting.");
client.stop();
// do nothing forevermore:
for(;;)
;
}
}
Thanks,
Doug.