Simple Web Server with Get String Parsing.

Projects Networking, Protocols, and Devices
1

I wrote this a while back when I could not find anything that worked the way that I wanted it to. I should have posted it sooner but it couldn't find the time.

Let me know if you have any questions, Its not the most elegant code, but it works and is a good place to start.

(see attached file)

webserver.pde (27.2 KB)

2

Would it be possible to get more comments on the code, im looking into using an ethernet shield equipped arduino as a webserver but havnt got a clue as to what your code is doing. A rundown of what is going on would be brilliant.

3

Some server test code I use to control two servos via a web page. With the serial monitor open, you can see what is being received by the server and how the get request is being parced.

//zoomkat 10-22-10
//routerbot code
//for use with IDE 0021
//open serial monitor to see what the arduino receives
//use a url like below
// http://192.168.1.102:84/?-1450-1550 

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

byte mac[] = { 
  0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED }; //physical mac address
byte ip[] = { 
  192, 168, 1, 102 }; // ip in lan
byte gateway[] = { 
  192, 168, 1, 1 }; // internet access via router
byte subnet[] = { 
  255, 255, 255, 0 }; //subnet mask
Server server(84); //server port

String readString, servo1, servo2; 

Servo myservo1;  // create servo object to control a servo 
Servo myservo2;
//////////////////////

void setup(){

  //start Ethernet
  Ethernet.begin(mac, ip, gateway, subnet);
  server.begin();

  //enable serial data print 
  Serial.begin(9600); 
  myservo1.attach(7);
  myservo2.attach(6);
  Serial.println("bot21"); // so I can keep track of what is loaded
}

void loop(){
  // Create a client connection
  Client client = server.available();
  if (client) {
    while (client.connected()) {
      if (client.available()) {
        char c = client.read();

        //read char by char HTTP request
        if (readString.length() < 100) {

          //store characters to string 
          readString += c; 
        } 

        //if HTTP request has ended
        if (c == '\n') {

          ///////////////
          Serial.println(readString);

          //readString looks like "GET /?-1500-1500 HTTP/1.1"

          if (readString.length() >0) {
            Serial.println(readString);

            servo1 = readString.substring(7, 11);
            servo2 = readString.substring(12, 16);

            Serial.println(servo1);
            Serial.println(servo2);

            int n1;
            int n2;

            char carray1[6];
            servo1.toCharArray(carray1, sizeof(carray1));
            n1 = atoi(carray1); 

            char carray2[6];
            servo2.toCharArray(carray2, sizeof(carray2));
            n2 = atoi(carray2); 

            myservo1.writeMicroseconds(n1);
            myservo2.writeMicroseconds(n2);

            //myservo.write(n);
            readString="";
          } 
          ///////////////////

          //now output HTML data header
          client.println("HTTP/1.1 204 Zoomkat");
          client.println();
          client.println();
          delay(1);
          //stopping client
          client.stop();

          /////////////////////
          //clearing string for next read
          readString="";

        }
      }
    }
  }
}