Arduino Ftp

edits.ino

 char *tStr = strtok(outBuf,"(");
 tStr = strtok(NULL,"(");

 if(tStr == NULL)
 {
   Serial.println("No parenthesis");    
 }
 
 unsigned int hiPort,loPort;

 sscanf(tStr,"%*u,%*u,%*u,%*u,%u,%u",&hiPort,&loPort);

ftp.ino

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

// reads from server and writes to SD file
// uncomment next line to write SD file to server.
// #define FTPWRITE

byte mac[] = { 0x90, 0xA2, 0xDA, 0x00, 0x59, 0x67 };  
IPAddress ip( 192, 168, 0, 2 );    
IPAddress gateway( 192, 168, 0, 1 );
IPAddress subnet( 255, 255, 255, 0 );

// FTP server ip
IPAddress server( 192, 168, 0, 3 );

EthernetClient client;
EthernetClient dclient;

char outBuf[128];
char outCount;

void setup()
{
 Serial.begin(9600);

 if(SD.begin(4) == 0)
 {
   Serial.println("SD init fail");          
 }

 Ethernet.begin(mac, ip, gateway, gateway, subnet); 
 digitalWrite(10,HIGH);
 delay(2000);
 Serial.println("Ready. Press f or r");
}

void loop()
{
 byte inChar;

 inChar = Serial.read();

 if(inChar == 'f')
 {
   if(doFTP()) Serial.println("FTP OK");
   else Serial.println("FTP FAIL");
 }

 if(inChar == 'r')
 {
   readSD();    
 }

}

File fh;

byte doFTP()
{
#ifdef FTPWRITE
 fh = SD.open("test.txt",FILE_READ);
#else
 SD.remove("test.txt");
 fh = SD.open("test.txt",FILE_WRITE);
#endif

 if(!fh)
 {
   Serial.println("SD open fail");
   return 0;    
 }

 Serial.println("SD opened");
 
 if (client.connect(server,21)) {
   Serial.println("Command connected");
 } 
 else {
   Serial.println("Command connection failed");
   fh.close();
   return 0;
 }

 if(!eRcv()) return 0;

// change to your user
 client.write("USER myusername\r\n");

 if(!eRcv()) return 0;

// change to your password  
 client.write("PASS mypassword\r\n");

 if(!eRcv()) return 0;

 client.write("SYST\r\n");

 if(!eRcv()) return 0;

 client.write("PASV\r\n");

 if(!eRcv()) return 0;

// new code

 char *tStr = strtok(outBuf,"(,");
 int array_pasv[6];
 for ( int i = 0; i < 6; i++) {
   tStr = strtok(NULL,"(,");
   array_pasv[i] = atoi(tStr);
   if(tStr == NULL)
   {
     Serial.println("Bad PASV Answer");    
     client.stop();
     fh.close(); 
     return 0;  
   }
 }

 unsigned int hiPort,loPort;

 hiPort = array_pasv[4] << 8;
 loPort = array_pasv[5] & 255;

// end of new code

 Serial.print("Data port: ");
 hiPort = hiPort | loPort;
 Serial.println(hiPort);
 
 if (dclient.connect(server,hiPort)) {
   Serial.println("Data connected");
 } 
 else {
   Serial.println("Data connection failed");
   client.stop();
   fh.close();
   return 0;
 }

#ifdef FTPWRITE 
 client.write("STOR /test.txt\r\n");
#else
 client.write("RETR /test.txt\r\n");
#endif

 if(!eRcv())
 {
   dclient.stop();
   return 0;
 }

#ifdef FTPWRITE
 Serial.println("Writing");

// This needs improvement

 while(fh.available())
 {
   char c = fh.read();
   dclient.write(c);
 }

#else
 while(dclient.connected())
 {
   while(dclient.available())
   {
     char c = dclient.read();
     fh.write(c);      
     Serial.write(c); 
   }
 }
#endif

 dclient.stop();
 Serial.println("Data disconnected");
 
 if(!eRcv()) return 0;

 client.write("QUIT\r\n");

 if(!eRcv()) return 0;

 client.stop();
 Serial.println("Command disconnected");

 fh.close();
 Serial.println("SD closed");
 return 1;
}

byte eRcv()
{
 byte respCode;
 byte thisByte;

 while(!client.available()) delay(1);

 respCode = client.peek();

 outCount = 0;
 
 while(client.available())
 {  
   thisByte = client.read();    
   Serial.write(thisByte);

   if(outCount < 127)
   {
     outBuf[outCount] = thisByte;
     outCount++;      
     outBuf[outCount] = 0;
   }
 }

 if(respCode >= '4')
 {
   efail();
   return 0;  
 }

 return 1;
}


void efail()
{
 byte thisByte = 0;

 client.write("QUIT\r\n");

 while(!client.available()) delay(1);

 while(client.available())
 {  
   thisByte = client.read();    
   Serial.write(thisByte);
 }

 client.stop();
 Serial.println("Command disconnected");
 fh.close();
 Serial.println("SD closed");
}

void readSD()
{
 fh = SD.open("test.txt",FILE_READ);

 if(!fh)
 {
   Serial.println("SD open fail");
   return;    
 }

 while(fh.available())
 {
   Serial.write(fh.read());
 }
 
 fh.close();
}

instructions.txt

he "#define FTPWRITE" determines whether it reads or writes to the FTP server. Commented out, it reads from the FTP server and writes to the SD.

Change your network settings, and the user/password in the doFTP() routine.
Place a file named test.txt in your FTP server.

Upload and open serial monitor. Wait for ready. 
Press 'r' and enter to view SD file contents.
Press 'f' and enter to transfer.