Hi Gang
I'm thinking of purchasing the following RFID Module;
I found the following example code;
/*------------------------------------------------------------------
This is a sample code for RDM630 RFID reader by Spekel(Spekel.se)
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.
http://creativecommons.org/licenses/by-nc-sa/3.0/
-------------------------------------------------------------------*/
#include <SoftwareSerial.h>
#define rxPin 2
#define txPin 3
char code[20];
int val = 0;
int bytesread = 0;
//------------------------------------
//create a Serial object RFID
SoftwareSerial RFID= SoftwareSerial(rxPin, txPin);
void setup()
{
Serial.begin(9600);
Serial.println("Serial Ready");
RFID.begin(9600);
Serial.println("RFID Ready");
pinMode(rxPin, INPUT);
pinMode(txPin, OUTPUT);
}
void loop()
{
val = 0;
bytesread = 0;
while(bytesread < 12)
{
// read 12 digit code
val = RFID.read();
if(val == 3)
{ // if header or stop bytes before the 10 digit reading
break; // stop reading
}
if(val != 2)
{
code[bytesread] = val; // add the digit
bytesread++; // ready to read next digit
code[bytesread] = '\0'; // add the NULL
}
}
if(bytesread >= 12)
{ // if 12 digit read is complete
Serial.print("Tag: [");
for(int i=0; code[i]!='\0' ; i++)
{
Serial.print(code[i]);
}
Serial.println("]"); //print the whole 13 bytes
}
}
I was wondering if someone could explain what the following two lines do;
code[bytesread] = '\0'; // add the NULL
and
for(int i=0; code[i]!='\0' ; i++)
specifically;
'\0'
Any help would be greatly appreciated.
Cheers
Jase