Ring reader

This is the firmware for my IoT RFID reader, intended to be used with 125kHz RFID rings.

Project page: https://articles.maximemoreillon.com/articles/03878fe3-1eca-4f22-9521-0589ba076930

Example application: https://articles.maximemoreillon.com/articles/523

More info about the hardware: https://oshwlab.com/m.moreillon/iot_em4305_reader