JMY502M is RFID reader/writer module with UART and IIC serial port. The RF protocol is complex. But the designer combined some frequent used command of RF card and then user could operate the cards with full function by sending simple command to the module through IIC or UART interface. And the module and antenna are separate design. The impedance between RF module and antenna was tuned by impedance analyzer. And then the module has excellent performance and stability. The module and antenna is separate design. 4 wires are linked the antenna and module. Normally the wire should be less than 200mm, or it will affect the module's performance and stability.

    Qualifications:
     PCD: FM1702SL
     Working frequency: 13.56MHz
     RF standard: ISO14443A
     Operating distance: 100mm(depending on card and antenna design)
     Anti collision ability: Full function anti collision; be able to process multi-cards simultaneously; be able to set operate single card only
     Auto detecting card: Supported, default ON
     EEPROM: 512 Bytes
     Interface: IIC & UART (selected by SPS pin, recommend to use IIC)
     Communication rate: IIC--400Kbps; UART--19.2Kbps/115.2Kbps
     Max.command length: 72 Bytes
     Interface level: 3.3V(TTL level; 5V tolerance)
     Power supply: DC 5.0V
     Power consumption: 70mA
     Dimension: 42mm×21mm×8mm
     Package: DIP32
     Weight: about 15g
     Operating temperature: -25 ~ +85 ℃ (-77 ~ +185°F)
     Storage temperature: -40 ~ +125 ℃ (-104 ~ +257°F)
     ISP: Supported
     RoHS: Compliant

Antenna connects to the module by 4 wires.
TX500, size: 70mm*70mm, 90mm reading range
TX501, size: 50mm*50mm, 70mm reading range
TX502, size: 30mm*30mm, 60mm reading range
Any requirements is available.