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RFID Read/Write Module - USB

  • 28540: RFID Read/Write Module, USB - front view
  • 28540: RFID Read/Write Module, USB - back view
  • 28540: RFID Read/Write Module, USB - alternate view
Product ID: 28540
In Stock: 426


Designed in cooperation with Grand Idea Studio, the Parallax Radio Frequency Identification (RFID) Read/Write Module USB provides a low-cost solution to read and write passive RFID transponder tags up to 4 inches away. The RFID R/W transponder tags provide a unique serial number and can store up to 116 bytes of user data, which can be password protected to allow only authorized access.

The RFID Read/Write Module can be used in a wide variety of hobbyist and commercial applications, including access control, user identification, robotics navigation, inventory tracking, payment systems, car immobilization, and manufacturing automation. This module's USB interface provides a direct connection to a computer.

Note that read/write distance will vary with tag type.

See our RFID Module & Tag Compatibility Chart here.


  • Low-cost method for reading and writing passive, 125 kHz RFID transponder tags
  • Up to 116 bytes of user data storage on a single tag
  • Optional security features prevent tag from being read or written without password
  • Bi-color LED for visual indication of status
  • USB mini-B connector for power and communication


Key Specifications

  • Power requirements: 5 VDC via USB, approx. 20mA idle, 100mA typical active
  • Communication: asynchronous serial 9600 bps (8N1) via USB virtual COM port
  • Dimensions: 3.25 x 2.45 in (8.26 x 6.2 cm)
  • Tag compatibility (Read/Write): EM Microelectronics EM4x50 1kbit R/W transponder tags
  • Tag compatibility (Read-only): EM Microelectronics EM4100 Read-only tags

Downloads & Documentation

Product Specific Downloads
Download Details More Info
RFID Read/Write Module - USB Python Script - 7.91 KB | updated: 26 Feb 2018 - 6:30 pm
RFID Read/Write Module - USB Design Files - 286.14 KB | updated: 26 Feb 2018 - 5:16 pm
RFID Read/Write Module Product Guide - 1.11 MB | updated: 27 Feb 2018 - 1:17 pm

Additional Resources