MFRC5C522 is a combined reader and writer for RFID tags that comply with ISO/IEC 14443 like A/MIFARE and NTAG. The commonly available inexpensive boards have an SPI interface, we will make it talk with Explore M3 in this tutorial.
Hookup
The default SPI interface for Explore M3 is mapped to SPI1 of the controller. It simply means whenever you're interfacing an SPI device you used use these pins and functions like SPI.begin() will use these pins.
| Explore M3 | MFRC522 Breakout | Description | |
|---|---|---|---|
| 10 | MOSI | Master Out Slave In | |
| 11 | MISO | Master In Slave Out | |
| 12 | SCK | Serial Clock | |
| 13 | SDA | This is wrongly labelled, this should have been SS | |
| 5 | RESET | SPI reset signal |
