Hello, I have been struggling with this for a couple of days now:
I have network setup: Laptop - 3G dongle - wifi router( with RJ45 port ) - Switch - ArduinoUno+Ethernet ShieldW5100 (No SD card)
The 3G dongle in the wifi router provides a wireless internet connection, and by extending the network through the routers RJ45 jack I can create a LAN network with an internet connection.
I am attempting to setup a high speed real-time monitoring system
I have attempted the WebServer example but the browser displays that the IP address is being rejected or not available 
I have attempted the following test code
#include <SPI.h>
#include <Ethernet.h>
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
byte gateway[] = {192, 168, 169, 1}; // router IP
byte subnet[] = {255, 255, 255, 0};
IPAddress ip(192,168,169,7); // I have tried many different numbers but 7 is my lucky one , atleast in roulet
void setup() {
Serial.begin(9600);
// disable SD SPI
pinMode(4,OUTPUT);
digitalWrite(4,HIGH);
// Start ethernet
Serial.print(F("Starting ethernet..."));
Ethernet.begin(mac, ip, gateway, gateway, subnet);
Serial.println(Ethernet.localIP());
delay(2000);
Serial.println(F("Ready"));
}
void loop() {
}
The serial monitor returns: "starting ethernet 0.0.0.0" Ready"
and the following DHCP connection example code:
//zoomkat 11-04-13
//simple client test
//for use with IDE 1.0.1
//with DNS, DHCP, and Host
//open serial monitor and send an e to test client GET
//for use with W5100 based ethernet shields
//remove SD card if inserted
//data from myIP server captured in readString
#include <SPI.h>
#include <Ethernet.h>
String readString;
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED }; //physical mac address
char serverName[] = "checkip.dyndns.com"; // zoomkat's test web page server
EthernetClient client;
//////////////////////
void setup(){
if (Ethernet.begin(mac) == 0) {
Serial.println("Failed to configure Ethernet using DHCP");
// no point in carrying on, so do nothing forevermore:
while(true);
}
Serial.begin(9600);
Serial.println("client readString test 11/04/13"); // so I can keep track of what is loaded
Serial.println("Send an e in serial monitor to test"); // what to do to test
Serial.println();
}
void loop(){
// check for serial input
if (Serial.available() > 0) //if something in serial buffer
{
byte inChar; // sets inChar as a byte
inChar = Serial.read(); //gets byte from buffer
if(inChar == 'e') // checks to see byte is an e
{
sendGET(); // call sendGET function below when byte is an e
}
}
}
//////////////////////////
void sendGET() //client function to send/receive GET request data.
{
if (client.connect(serverName, 80)) { //starts client connection, checks for connection
Serial.println("connected");
client.println("GET / HTTP/1.1"); //download text
client.println("Host: checkip.dyndns.com");
client.println("Connection: close"); //close 1.1 persistent connection
client.println(); //end of get request
}
else {
Serial.println("connection failed"); //error message if no client connect
Serial.println();
}
while(client.connected() && !client.available()) delay(1); //waits for data
while (client.connected() || client.available()) { //connected or data available
char c = client.read(); //gets byte from ethernet buffer
readString += c; //places captured byte in readString
}
//Serial.println();
client.stop(); //stop client
Serial.println("client disconnected.");
Serial.println("Data from server captured in readString:");
Serial.println();
Serial.print(readString); //prints readString to serial monitor
Serial.println();
Serial.println();
Serial.println("End of readString");
Serial.println("==================");
Serial.println();
readString=""; //clear readString variable
}
The serial monitor does not return anything
I am stuck with the 3G dongle - Wifi Router with RJ45 port -Switch - hardware combo for another 2 months.
Please help with some ideas, I wonder if the router rejects the arduino, or the switch fail to transfer requests from the arduino to the server? Not sure if one of the cables should be crossover? ( I have a new laptop, dont know how to check if it is done internally )
Thank you in advance
