RC522 types

There are a few types of RC522 chips and boards.

Chip types

NXP has made RC522 chip as the heart of RFID boards. According to datasheet there are two revisions of RC522, but in fact there are a few more in a wild. The chips may (hopefully precisely) be identified by Version code obtained with reading VersionReg (37h register)

See also

1. README
2. datasheet