Interfacing Ethernet and SD card simultaneously

Server code that uploads some files from the SD card. Note the Ethernet shield disabling code at startup to allow the SD card to initialize, then reinstate the Ethernet shield.

//zoomkat 2/26/13
//SD server slider test code
//open serial monitor to see what the arduino receives
//browser address will look like http://192.168.1.102:84/servosld.htm when submited
//for use with W5100 based ethernet shields
//put the servosld.htm, slider.js, bluev_sl.gif,
//and bluev_bg.gif on the SD card
//download flies at:
// http://web.comporium.net/~shb/pix/servosld.htm
// http://web.comporium.net/~shb/pix/slider.js
// http://web.comporium.net/~shb/pix/bluev_bg.gif
// http://web.comporium.net/~shb/pix/bluev_sl.gif
// 

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

#include <Servo.h> 
Servo myservoa, myservob, myservoc, myservod;  // create servo object to control a servo 
Servo myservoe, myservof, myservog; // myservoh not used due to lack of another free pin
String readString, pos;

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
EthernetServer server(84); //server port

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

void setup(){

  Serial.begin(9600);

  // disable w5100 while setting up SD
  pinMode(10,OUTPUT);
  digitalWrite(10,HIGH);
  Serial.print("Starting SD..");
  if(!SD.begin(4)) Serial.println("failed");
  else Serial.println("ok");

  Ethernet.begin(mac, ip, gateway, gateway, subnet);

  //delay(2000);
  server.begin();
  Serial.println("Ready");

  myservoa.attach(2);  //the pin for the servoa control
  myservob.attach(3);  //the pin for the servob control
  myservoc.attach(5);  //the pin for the servoc control
  myservod.attach(6);  //the pin for the servod control 
  myservoe.attach(7);  //the pin for the servoa control
  myservof.attach(8);  //the pin for the servob control
  myservog.attach(9);  //the pin for the servoc control
  //myservoh.attach(10);  //the pin for the servod control 

}

void loop(){
  // Create a client connection
  EthernetClient 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; 
          //Serial.print(c);
        } 
        //if HTTP request has ended
        if (c == '\n') {

          ///////////////
          Serial.println(readString); //print to serial monitor for debuging

            //select proper header for file to be sent to browser

          client.println("HTTP/1.1 200 OK"); //send new page
          if(readString.indexOf("servosld") >=0) {
            client.println("Content-Type: text/html");
            client.println(); 
          }

          if(readString.indexOf("slider") >=0) {
            client.println("Content-Type: application/x-javascript");
            client.println(); 
          }

          if(readString.indexOf("bluev") >=0) {
            client.println("Content-Type: image/gif");
            client.println(); 
          }

          //select file to send to browser
          if(readString.indexOf("servosld") >=0) {
            File myFile = SD.open("SERVOSLD.HTM");
            if (myFile) {

              byte clientBuf[64];
              int clientCount = 0;              

              while (myFile.available()) 
              {
                clientBuf[clientCount] = myFile.read();
                clientCount++;

                if(clientCount > 63)
                {
                  client.write(clientBuf,64);
                  clientCount = 0;
                }                
              }
              if(clientCount > 0) client.write(clientBuf,clientCount);            
              myFile.close();
            }
          }

          if(readString.indexOf("slider") >=0) {
            File myFile = SD.open("slider.js");
            if (myFile) {

              byte clientBuf[64];
              int clientCount = 0;              

              while (myFile.available()) 
              {
                clientBuf[clientCount] = myFile.read();
                clientCount++;

                if(clientCount > 63)
                {
                  client.write(clientBuf,64);
                  clientCount = 0;
                }                
              }
              if(clientCount > 0) client.write(clientBuf,clientCount); 
              myFile.close();
            }
          }

          if(readString.indexOf("bluev_sl") >=0) {
            File myFile = SD.open("bluev_sl.gif");
            if (myFile) {

              byte clientBuf[64];
              int clientCount = 0;              

              while (myFile.available()) 
              {
                clientBuf[clientCount] = myFile.read();
                clientCount++;

                if(clientCount > 63)
                {
                  client.write(clientBuf,64);
                  clientCount = 0;
                }                
              }
              if(clientCount > 0) client.write(clientBuf,clientCount); 
              myFile.close();
            }
          }

          if(readString.indexOf("bluev_bg") >=0) {
            File myFile = SD.open("bluev_bg.gif");
            if (myFile) {

              byte clientBuf[64];
              int clientCount = 0;              

              while (myFile.available()) 
              {
                clientBuf[clientCount] = myFile.read();
                clientCount++;

                if(clientCount > 63)
                {
                  client.write(clientBuf,64);
                  clientCount = 0;
                }                
              }
              if(clientCount > 0) client.write(clientBuf,clientCount); 
              myFile.close();
            }
          }

          delay(1);
          //stopping client
          client.stop();

          //process GET string request from client and and position servo

          pos = readString.substring(8, 12); //get the first four characters         
          //Serial.println(pos);
          int n = pos.toInt();  //convert readString into a number   
          Serial.println(n); 
          Serial.println();

          if(readString.indexOf("?0") >0) myservoa.writeMicroseconds(n);
          if(readString.indexOf("?1") >0) myservob.writeMicroseconds(n);
          if(readString.indexOf("?2") >0) myservoc.writeMicroseconds(n);
          if(readString.indexOf("?3") >0) myservod.writeMicroseconds(n);
          if(readString.indexOf("?4") >0) myservoe.writeMicroseconds(n);
          if(readString.indexOf("?5") >0) myservof.writeMicroseconds(n);
          if(readString.indexOf("?6") >0) myservog.writeMicroseconds(n);
          //only seven servo pins, so back to myservoa for testing
          if(readString.indexOf("?7") >0) myservoa.writeMicroseconds(n);

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