Symbol Description 7 to 4 Chiptype ‘9’ stands for MFRC522 3 to 0 Version ‘1’ stands for MFRC522 version 1.0 and ‘2’ stands for MFRC522 version 2.0. MFRC522 version 1.0 software version is: 91h. MFRC522 version 2.0 software version is: 92h. MFRC522 All information
