Reading Speed on RFID Reader

Other Hardware Sensors
1

Hi!
I am using a 125Khz RFID module RDM6300 - UART to read RFID Cards. With an example. Is there any way to make the readings faster. Sometimes I have to keep the card close like 0.5 seconds. We would like to make it faster.

#include <SoftwareSerial.h>
#include <avr/pgmspace.h>
//----
// Tags are stored in program flash memory
// 32k minus sketch size determines the amount of tags that can be stored
// Tags include the two CRC bytes (14 bytes total)
prog_char tag_0[] PROGMEM = "000000000000"; //add your tags here
prog_char tag_1[] PROGMEM = "000000000000";
prog_char tag_2[] PROGMEM = "000000000000";
prog_char tag_3[] PROGMEM = "000000000000";
prog_char tag_4[] PROGMEM = "000000000000";
prog_char tag_5[] PROGMEM = "000000000000";
prog_char tag_6[] PROGMEM = "000000000000";

PROGMEM const char *tag_table[] =
{   
  tag_0,
  tag_1,
  tag_2,
  tag_3,
  tag_4,
  tag_5,
  tag_6 };
//----

SoftwareSerial rfidReader(2,3); // Digital pins 2 and 3 connect to pins 1 and 2 of the RMD6300
String tagString;
char tagNumber[14];
boolean receivedTag;
int lockPIN=7; // pin 7 is controls the door

void setup() {
  
  pinMode(lockPIN,OUTPUT);
  Serial.begin(9600);
  rfidReader.begin(9600); // the RDM6300 runs at 9600bps
  Serial.println("\n\n\nRFID Reader...ready!");
 
}

void loop()
{
  receivedTag=false;
  while (rfidReader.available()){
    int BytesRead = rfidReader.readBytesUntil(3, tagNumber, 15);//EOT (3) is the last character in tag 
    receivedTag=true;
  }  
 
  if (receivedTag){
    tagString=tagNumber;
    Serial.println();
    Serial.print("Tag Number: ");
    Serial.println(tagString);
    
    if (checkTag(tagString)){
      Serial.print("Tag Authorized...");
      openDoor();
    }
    else{
      Serial.print("Unauthorized Tag: ");
      Serial.println(tagString);
      delay(1500); // a delay of 1500ms and a flush() seems to stop tag repeats
      rfidReader.flush();
    }
    memset(tagNumber,0,sizeof(tagNumber)); //erase tagNumber
  }
    
}

// ----
// checkTag function (give it the tag string complete with SOT and EOT)
// compares with tags in tag_table
// and returns true if the tag is in the list

 boolean checkTag(String tag){
   char testTag[14];
   
   for (int i = 0; i < sizeof(tag_table)/2; i++)
  {
    strcpy_P(testTag, (char*)pgm_read_word(&(tag_table[i])));
    if(tag.substring(1,13)==testTag){//substring function removes SOT and EOT
      return true;
      break;
    }
  }
   return false;
 }
 //----
 
 void openDoor(){
  Serial.print("Opening door...");
  digitalWrite(lockPIN,HIGH);
  delay(1000);
  Serial.println("Re-locking door");
  digitalWrite(lockPIN,LOW);
  delay(1500);// a delay of 1500ms and a flush() seems to stop tag repeats
  rfidReader.flush();
}

Thanks in advance.

Regards,
Daniel

2

There is definite time required to read the tag. The tag has no battery so there is a need for the reader to charge the tag power supply before it can then Tx the ID.

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