SIM5218 What does this bit (section not data XD )mean? [solved]

Projects Programming
1

I understand the serial.write bit, and I know that the 0x1A means end of data, but what do the two following lines mean?
So thats the question above. Now for a description?
Basically using the 3g shield I'm planning on sending data to a FTP server. The section I'm confused by is the bit where the text file is created then sent. Three bytes are being sent, one i know is the end of data byte... what are the other two? Error checking? but doesn't that change depending on whats in the data?

I got the code from Cooking Hacks page : http://www.cooking-hacks.com/index.php/documentation/tutorials/arduino-3g-gprs-gsm-gps

 Serial.println("01234567890123456789");    //Data for the file
    Serial.write(0x1A); //End of Data 
    Serial.write(0x0D);
    Serial.write(0x0A);

from this:

int led = 13;
int onModulePin = 2;        // the pin to switch on the module (without press on button) 

char data[1024];
int x=0;
int file_size;

char server[ ]="";
char port[ ]="";
char user_name[ ]="";
char password[ ]="";

void switchModule(){
    digitalWrite(onModulePin,HIGH);
    delay(2000);
    digitalWrite(onModulePin,LOW);
}

void setup(){

    Serial.begin(115200);                // UART baud rate
    delay(2000);
    pinMode(led, OUTPUT);
    pinMode(onModulePin, OUTPUT);
    switchModule();                    // switches the module ON

    for (int i=0;i< 5;i++){
        delay(5000);
    } 

    Serial.println("AT+CGSOCKCONT=1,\"IP\",\"myapn\"");    
    Serial.flush();
    x=0;
    do{
        while(Serial.available()==0);
        data[x]=Serial.read();  
        x++;                        
    }while(!(data[x-1]=='K'&&data[x-2]=='O'));
}

void loop()
{

    Serial.print("AT+CFTPSERV=\""); //Sets the FTP server
  Serial.print(server);
  Serial.println("\""); 
    Serial.flush();
    x=0;
    do{
        while(Serial.available()==0);
        data[x]=Serial.read();  
        x++;  
    }while(!(data[x-1]=='K'&&data[x-2]=='O'));

    Serial.print("AT+CFTPPORT=");    //Sets FTP port
  Serial.println(port);
    Serial.flush();
    x=0;
    do{
        while(Serial.available()==0);
        data[x]=Serial.read();  
        x++;  
    }while(!(data[x-1]=='K'&&data[x-2]=='O'));

    Serial.print("AT+CFTPUN=\""); //Sets the user name
  Serial.print(user_name);
  Serial.println("\""); 
    Serial.flush();
    x=0;
    do{
        while(Serial.available()==0);
        data[x]=Serial.read();  
        x++;  
    }while(!(data[x-1]=='K'&&data[x-2]=='O'));

    Serial.print("AT+CFTPPW=\""); //Sets password
  Serial.print(password);
  Serial.println("\"");     
    Serial.flush();
    x=0;
    do{
        while(Serial.available()==0);
        data[x]=Serial.read();  
        x++;  
    }while(!(data[x-1]=='K'&&data[x-2]=='O'));

    Serial.println("AT+CFTPMODE=1");    //Selects pasive mode
    Serial.flush();
    x=0;
    do{
        while(Serial.available()==0);
        data[x]=Serial.read();  
        x++;  
    }while(!(data[x-1]=='K'&&data[x-2]=='O'));

    Serial.println("AT+CFTPTYPE=A");    //Selects ASCII mode
    Serial.flush();
    x=0;
    do{
        while(Serial.available()==0);
        data[x]=Serial.read();  
        x++;  
    }while(!(data[x-1]=='K'&&data[x-2]=='O'));

    Serial.println("AT+CFTPPUT=\"/test.txt\"");    //Creates a file and sends data (ASCII)
    Serial.flush(); 
    while(Serial.read()!='N');    //Waits 'N' from BEGIN

    Serial.println("01234567890123456789");    //Data for the file
    Serial.write(0x1A); //End of Data //EOL character
    Serial.write(0x0D);
    Serial.write(0x0A);

    x=0;

    do{
        while(Serial.available()==0);
        data[x]=Serial.read(); 
        x++;  
    }while(!(data[x-1]=='K'&&data[x-2]=='O'));


    delay(1000);

    Serial.println("AT+CFTPGET=\"/test.txt\"");    //Reads the data from test file
    Serial.flush();

    x=0;
    do{
        while(Serial.available()==0);
        data[x]=Serial.read();  
        x++;  
    }while((data[x-1]!=','));

    x=0;
    
    while(Serial.peek()!=0x0A){
        file_size=(file_size*10)+(Serial.read()-0x30);
    }; 

    for(x=0;x< file_size;x++){
        while(Serial.available()==0);
        data[x]=Serial.read();
    }
    
    Serial.print(data);

    while(1);


}

Moderator edit: Marked thread solved. (Nick Gammon)

2

Carriage return, line feed.

They mean, move to a new line.

If you need to know more, google "CRLF".

3

Carriage return, line feed.

So if i were to send multiple lines of data, would i put the between the lines, then end data once, or EOD CRLF after each line?

4

Yep.

You could also do this:

    Serial.println("01234567890123456789");    //Data for the file - interestingly, this also adds new line characters.
    Serial.write(0x1A); //End of Data 
    Serial.println(); //Adds the new line characters

println() adds the new line characters for you.

5

Thanks
(how do i mark this as solved?)