NFC RFID Module PN532

Most of RFID modules are hardwired for SPI communication. This module, however, is not. The PN532 is an NFC RFID module clocked at 13.56MHz. What's special about this is that it has an onboard switch that you can use to easily change between I2C, SPI, and TTL Serial. It also has an integrated logic level shifter so you can use either 3.3V or 5V. Note that this module gets warm in normal operation. 

Specifications: 

• Supports I2C, SPI, and HSU (High-Speed UART), easy to switch between these modes.
  
• Works in the NFC mode and RFID reader/writer mode
  
• The integrated 3.3V voltage regulator provides 3.3V or 5V working voltage for your choice
  
• Maximum distance for communication: 3 cm
  
• Equipped with two 3mm mounting holes, easy to use in your project with its small dimension

• Tutorial 1
• Tutorial 2
• Tutorial 3