125Khz RFID module - UART

Introduction

RDM 125KHz card mini-module is designed for reading code from 125KHz card compatible read-only tags and read/write card . It can be applied in office/home security, personal identification, access control, anti-forgery, interactive toy and production control systems etc.

Note: Module will notify whenever 125khz tag approaches, tag serial number will be send via TX pin. Easy way for a RFID module on MCU projects or PC connnection via UartSB.

Features

• Support external antenna
• Maximum effective distance up to 50mm
• Less than 100ms decoding time
• UART TTL interface
• Support EM4100 compatible read only or read/write tags
• Built-in external bi-color LED and buzzer driver
• Small outline design

Specification

May include key specification and other specifications.

Key Specification

Frequency	125KHz
Baud Rate	9600 (TTL Electricity Level RS232 format)
interface	Weigang26 Or TTL Electricity Level RS232 format
Power supply	DC 5V（±5%）
Current	<50Ma
Operating range	>50mm(Depend on Card/Tag shape, manufacturer)
Expand I/O port	N/A
Indication light	N/A
Working temperature	-10℃~ +70℃
Storage temperature	-20℃~ +80℃
Max. humidity	Relative humidity 0 ~ 95%
Size	38.5mm ×19mm×9mm

Pin definition and Rating

Look the image below(Mechanic Dimensions), and check the pin definition list here:

 Pin Definition :
 P1:
   PIN1    TX
   PIN2    RX
   PIN3
   PIN4    GND
   PIN5    +5V(DC)
 P2:
   PIN1    ANT1
   PIN2    ANT2
 P3:
   PIN1    LED
   PIN2    +5V(DC)
   PIN3    GND

Mechanic Dimensions

Usage

TTL Interface RS232 Data output format

1. 9600bps,N,8,1
2. CHECKSUM: card 10byte DATA entire do XOR operation

   02

   10ASCII Data Characters

   Chechsum

   03

Example: card number: 62E3086CED

• Output data:36H、32H、45H、33H、30H、38H、36H、43H、45H、44H
• CHECKSUM: (62H) XOR (E3H) XOR (08H) XOR (6CH) XOR (EDH)=08H

Time sequence chart

Exampel

Output date(HEX): 02 | 30 31 30 30 30 37 33 34 45 30 | 44 32 | 03 ->Change to Decimal CardNumber Decimal: 48 49 48 48 48 55 51 52 69 48 CheckSum Decimal: 68 50 ->Refer to ASCII table,get Ascill value CardNumber Ascill: 0 1 0 0 0 7 3 4 E 0 CheckSum Ascill : D 2 (01H) xor (00H) xor (07H) xor (34H) xor (E0H) = D2H

Programming

Connect RX/TX to Arduino UART port , Uart demo code :

void setup()
{
  Serial.begin(9600);
}
void loop()
{
  if(Serial.available())
  {
    while(Serial.available())
    Serial.write(Serial.read());
  }
}

Resources

• Datasheet: RDM630-Spec.pdf

• How to connect Arduino and RFID

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