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[on:]

I'm trying to get the WebClient example running but always get "connection failed".

The google ip is ok and 173.194.35.8/search?q=arduino works in Firefox.
I also have Arduino running as server without problems so my network settings are ok.
It's the official Ethernet Shield.

Code:

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

/**************************************************************
*                      Ethernet Settings                      *
**************************************************************/
// Ethernet Card Mac Address
byte mac[] = {0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF};
// IPv4 address
byte ip[] = {192, 168, 0, 60};
// Subnet mask
byte subnet[] = {255, 255, 255, 0};
// Default gateway
byte gateway[] = {192, 168, 0, 1};
// Preferred DNS sever
// byte dns[] = {192, 168, 0, 1};

IPAddress server(173,194,35,8); // 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
  }

  Ethernet.begin(mac, ip, subnet, gateway);
  delay(1000);
  Serial.println("connecting...");

  // if you get a connection, report back via serial:
  if (client.connect(server, 80)) {
    Serial.println("connected");
    // Make a HTTP request:
    client.println("GET /search?q=arduino 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(;;)
      ;
  }
}

[Reply #1 on:]

Try this code example from the wiki (playground). It has been thoroughly tested.
http://playground.arduino.cc/Code/WebClient
If you have problems with it, post here and I will try to help.

edit: Hey!! How about that? I'm using the wiki instead of posting all that code again!! 

[Reply #2 on:]

Ok, this one works - thanks. But looks like it's not a good idea to make a
google search. To much html, javascript and css for the Mega...

But hey you are the FTP guy.
I will write in that FTP thread in a minute

[Reply #3 on:]

Not really too much html. The part that slows the whole process up is the Serial output at 9600 baud. Kick that up to a reasonable rate, or use it for debugging only, and it will really smoke! 

[Reply #4 on:]

Hey, Tim. I tried that code, too. It eventually works, but, I'm wondering why you have a wait, do something, wait, do something, methodology, instead of a do something, wait, do something, wait, methodology.

Changing the initial value of loopCount to 30 makes it do something immediately, and then wait 30 seconds.

[Reply #5 on:]

Hi Paul! My routers have a time delay between the time the ip/mac address is available on the network until the router puts that ip/mac in the ARP table. If you can guarantee your router will get the ARP table update in less than 2 seconds, go for it!

[Reply #6 on:]

It's not the delay() in setup() that is the issue. It is that once loop() is called, nothing happens for 30 seconds. By the time loop() is called, the Ethernet shield/class should be ready to do stuff. It should, then, in my opinion, get busy doing something, and then wait so as not to overwhelm the server.

[Reply #7 on:]

That is correct. My router SOMETIMES takes longer than that 2 seconds to put the ip/mac in the ARP table. So I use the additional 30 seconds to allow the router time to get all in order.

I am testing on a really busy network. I have 300 users in the network database, and a lot of them use Netflix.

Like I said, if you can guarantee...

[Reply #8 on:]

Like I said, if you can guarantee...

I was asking why. Your first response seemed to address the delay in setup(). Now, it appears that you do have a good reason for the wait/do/wait/do methodology, rather than the do/wait/do/wait methodology. I'm fine with that.

[Reply #9 on:]

I'm glad you brought it up. If you are on a private network with 2 computers and the Arduino, the 30 second delay is probably not necessary. You could very well switch the 30 second delay after the first request.