For starters, you need a pre-wired NFC RFID module as the key hardware. NFC and RFID projects have become a huge trend, but many modules are pricey for electronics hobbyists and need a complex setup.

When running a PN532 over I2C, the device functions after power loss/restoration, and every other soft reboot. When it is provided power, and every second soft reboot, it provides the following during ...

C:\Users\LingChingYan\Documents\Arduino\libraries\Adafruit_PN532\Adafruit_PN532.cpp: In function 'void i2c_send(uint8_t)': C:\Users\LingChingYan\Documents\Arduino ...