W5100 ethernet shield with Uno

Good evening,

I recently purchased a W5100 Ethernet shield for use with my Arduino uno. HR911105A.

I’ve been trying to set up it for hours now and cant seem to get anywhere. I’ve done some research online and haven’t found anything super helpful yet. Anyone else that has a problem with their shield seems to get no lights on their shield however I do. When my arduino is powered and an ethernet cable is plugged into the shield I get lights on the ethernet port and several LEDs light up on the board (link,100M,FULLD,COLL)

Yet with all the test code I’ve tried I get no response. In many of the programs I’ve used I will assign an IP to the arduino and have the serial monitor respond with said IP but that’s all it gets to, nothing happens after that.

For example this test code:

#include <Dhcp.h>
#include <Dns.h>
#include <Ethernet.h>
#include <EthernetClient.h>
#include <EthernetServer.h>
#include <EthernetUdp.h>
#include <Twitter.h>
#include <util.h>
#include <utility/w5100.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, 0xEE
IPAddress ip(x, x, x, x);

// Initialize the Ethernet server library
// with the IP address and port you want to use
// (port 80 is default for HTTP):
EthernetServer server(80);

void setup() {
  // Open serial communications and wait for port to open:
  while (!Serial) {
    ; // wait for serial port to connect. Needed for native USB port only

  // start the Ethernet connection and the server:
  Ethernet.begin(mac, ip);
  Serial.print("server is at ");

void loop() {
  // listen for incoming clients
  EthernetClient client = server.available();
  if (client) {
    Serial.println("new client");
    // an http request ends with a blank line
    boolean currentLineIsBlank = true;
    while (client.connected()) {
      if (client.available()) {
        char c = client.read();
        // if you've gotten to the end of the line (received a newline
        // character) and the line is blank, the http request has ended,
        // so you can send a reply
        if (c == '\n' && currentLineIsBlank) {
          // send a standard http response header
          client.println("HTTP/1.1 200 OK");
          client.println("Content-Type: text/html");
          client.println("Connection: close");  // the connection will be closed after completion of the response
          client.println("Refresh: 5");  // refresh the page automatically every 5 sec
          client.println("<!DOCTYPE HTML>");
          // output the value of each analog input pin
          for (int analogChannel = 0; analogChannel < 6; analogChannel++) {
            int sensorReading = analogRead(analogChannel);
            client.print("analog input ");
            client.print(" is ");
        if (c == '\n') {
          // you're starting a new line
          currentLineIsBlank = true;
        } else if (c != '\r') {
          // you've gotten a character on the current line
          currentLineIsBlank = false;
    // give the web browser time to receive the data
    // close the connection:
    Serial.println("client disconnected");

My serial monitor will print the "server is at " portion but nothing happens after that at all. And I’ve tried pinging the IP i select with no response.

I also tried this code I found on the forum:

//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 weather 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[] = "api.openweathermap.org"; // myIP server 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:

  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

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
    client.println("GET /data/2.5/weather?zip=46526,us HTTP/1.1"); //download text
    client.println("Host: api.openweathermap.org");
    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

  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

  client.stop(); //stop client
  Serial.println("client disconnected.");
  Serial.println("Data from server captured in readString:");
  Serial.print(readString); //prints readString to serial monitor 
  Serial.println("End of readString");
  readString=""; //clear readString variable


And I get absolutely nothing in my serial monitor, not even “Failed to configure Ethernet using DHCP”

Any ideas on what is wrong or what I’m doing wrong?

Thanks for any help.

A link to the ethernet shield hardware might help. No SD card in the shield's slot, right?

BTW, the HR911105A is the part number for the RJ45 socket, not the shield.

I apologize, the shield is http://www.ebay.com/itm/322267901919?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

And yes no SD card in slot.

It could be a bad IC or faulty assembly. Some cheaper boards have solder bridges or bad solder joints.

Could be. I've done a little more research and it seems these boards have a notorious problem with having a completely wrong resistor right after the RJ45 jack. Will be a pain to fix...

Check SurferTims advice about solder joints and the problem with wrong termination resistors, are
described in Ethernet sheild(W5100) not working with Uno - Networking, Protocols, and Devices - Arduino Forum

Hope you have the courage to try.