Read Arduino HTML Upload

edited October 2013 in Arduino

Hi all.

I am using the following Arduino code to upload my sensor values to an HTML page (locally). However, when I am trying to read the HTML values using the HTTPClient Processing example, I get the following, without the sensor values. Can someone explain what is wrong? Thanks!

HTTPClient Console:


Arduino code:

// zoomkat's meta refresh data frame test page 5/25/13
// use in your brouser for main page
// static data page
// meta refresh data page
// for use with W5100 based ethernet shields
// set the refresh rate to 0 for fastest update
// use STOP for single data updates

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

const int analogInPin0 = A0;
const int analogInPin1 = A1;
const int analogInPin2 = A2;
const int analogInPin3 = A3;
const int analogInPin4 = A4;
const int analogInPin5 = A5;

byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED }; //physical mac address
byte ip[] = { 10, 0, 1, 15 }; // arduino ip in lan
byte gateway[] = { 10, 0, 1, 255 }; // internet access via router
byte subnet[] = { 255, 255, 255, 0 }; //subnet mask
EthernetServer server(80); //server port
unsigned long int x=0; //set refresh counter to 0
String readString; 


void setup(){
    // disable SD SPI if memory card in the uSD slot

  Ethernet.begin(mac, ip, gateway, gateway, subnet);
  Serial.println("meta refresh data frame test 5/25/13"); // so I can keep track of what is loaded

void loop(){
  EthernetClient client = server.available();
  if (client) {
    while (client.connected()) {
      if (client.available()) {
        char c =;
         if (readString.length() < 100) {
          readString += c; 
        //check if HTTP request has ended
        if (c == '\n') {

          //check get atring received

          //output HTML data header
          client.println("HTTP/1.1 200 OK");
          client.println("Content-Type: text/html");

          //generate data page
          if(readString.indexOf("data") >0) {  //checks for "data" page
            x=x+1; //page upload counter
            //meta-refresh page every 1 seconds if "datastart" page
            if(readString.indexOf("datastart") >0) client.print("<meta http-equiv='refresh' content='1'>"); 
            //meta-refresh 0 for fast data
            if(readString.indexOf("datafast") >0) client.print("<meta http-equiv='refresh' content='0'>"); 
            client.print("<title>Zoomkat's meta-refresh test</title></head><BODY><br>");
            client.print("page refresh number: ");
            client.print(x); //current refresh count

              //output the value of each analog input pin
            client.print("analog input0 is: ");

            client.print("<br>analog input1 is: ");

            client.print("<br>analog input2 is: ");

            client.print("<br>analog input3 is: ");

            client.print("<br>analog input4 is: ");

            client.print("<br>analog input5 is: ");
          //generate main page with iframe
            client.print("<HTML><HEAD><TITLE>Zoomkat's frame refresh test</TITLE></HEAD>");
            client.print("Zoomkat's Arduino frame meta refresh test 5/25/13");
            client.print("<BR><BR>Arduino analog input data frame:<BR>");
            client.print("&nbsp;&nbsp;<a href='/datastart' target='DataBox' title=''yy''>META-REFRESH</a>");
            client.print("&nbsp;&nbsp;&nbsp;&nbsp;<a href='/data' target='DataBox' title=''xx''>SINGLE-STOP</a>");
            client.print("&nbsp;&nbsp;&nbsp;&nbsp;<a href='/datafast' target='DataBox' title=''zz''>FAST-DATA</a><BR>");
            client.print("<iframe src='/data' width='350' height='250' name='DataBox'>");
          //stopping client
          //clearing string for next read


  • Looks like the test

    if(readString.indexOf("data") >0) 

    always fails, so you get the alternative.

    Which seems incorrect. Why do you have double single-quotes around the values of the title attribute?

  • The example is taken from the Arduino forum as it is above. One suggestion I got from Arduino forum is to use the address: in order to get my information, however I can't make this to work. If someone else has different results, please let me know

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