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[on:]

Hi folks

I'm a Arduino (also programming) beginner  and I have problem connecting Arduino Uno + Enternet Shield with the standard WEB CLIENT Sketch

The program doesn't enter in the "If" condition [client.connect()]but I really don't understand why.

At the same time the WebServer sketch works perfectly....(so I suppose that IP & MAC address are fine)

I'm working inside a private network (so Arduino IP isn't public): could this be a problem on client connection? (even if the server works?)

Anyone could help me?

following the (well known) code:

#include <SPI.h>
#include <Ethernet.h>

// Enter a MAC address and IP address for your controller below.
// The IP address will be dependent on your local network:
byte mac[] = {  0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
byte ip[] = { 10,172,85,203 };

byte server[] = { 209,85,148,106 }; // 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):
Client client(server, 80);

void setup()
{
  Ethernet.begin(mac, ip);
  Serial.begin(9600);

  delay(1000);

  Serial.println("connecting...");

  if (client.connect()) { //Here where I can't enter in !!
    Serial.println("connected");
    client.println("GET /search?q=arduino HTTP/1.0");
    client.println();
  } else {
    Serial.println("connection failed");
  }
}

void loop()
{
  if (client.available()) {
    char c = client.read();
    Serial.print(c);
  }

  if (!client.connected()) {
    Serial.println();
    Serial.println("disconnecting.");
    client.stop();
    for(;
      ;
  }
}

[Reply #1 on:]

http://www.selfseo.com/find_ip_address_of_a_website.php
Use this link to find the IP address that a URL points to. Try a couple of different IP addresses for URL that you can access from the same network that the Arduino is connected to.

If your PC can access the site by IP address, the Arduino should be able to.

[Reply #2 on:]

Some simple client test code you can try. Use the tool bar # code tag for posting your code.

Code:

//zoomkat 12-01-11
//simple client test
//for use with IDE 0021
//open serial monitor and send an e to test
//for use with W5100 based ethernet shields

#include <SPI.h>
#include <Ethernet.h>

byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED }; //physical mac address
byte ip[] = { 192, 168, 1, 102 }; // ip in lan assigned to arduino
//byte gateway[] = { 192, 168, 1, 1 }; // internet access via router
//byte subnet[] = { 255, 255, 255, 0 }; //subnet mask
byte myserver[] = { 208, 104, 2, 86 }; // zoomkat web page server IP address
Client client(myserver, 80);  // connect to web server using port 80

//////////////////////

void setup(){

  Ethernet.begin(mac, ip);
  //Ethernet.begin(mac, ip, gateway, subnet);
  Serial.begin(9600);
  Serial.println("Better client test 12/01/11"); // so I can keep track of what is loaded
  Serial.println("Send an e in serial monitor to test"); // what to do to test
}

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()) {  //starts client connection, checks for connection
    Serial.println("connected");
    client.println("GET /~shb/arduino.txt HTTP/1.0"); //download text
    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
    Serial.print(c); //prints byte to serial monitor
  }

  Serial.println();
  Serial.println("disconnecting.");
  Serial.println("==================");
  Serial.println();
  client.stop(); //stop client

}

[Reply #3 on:]

@zoomkat

I tried your code but no way: I arrive till "sendGET()" and then I receive a "connection failed" after waiting a bunch of second on " if (client.connect())"

Could it be a sort of Ms Xp Bugs?

[Reply #4 on:]

Could it be a sort of Ms Xp Bugs?

No, works fine on my xp machine. You may need to read and study more postings on client/lan/internet connections. You will need to consider the network you are connecting to (lan, router, and such) to see why the connecion is failing. If you are behind a router, make sure the ip address you assign to the arduino is compatable with the router and not in use by another device.