I’ve been working on a freestyle libre glucose monitor reader. the sensor tag uses ISO/IEC 15693 to communicate with the NFC reader. following the work of @JoernL I’ve purchased a CR95HF based reader and connected it to my esp32. the original design used arduino pro-mini, but i’ve opted to use adafruit huzzah feather esp32 as it includes all the peripherals needed: batter charger, bluetooth, and WiFi support so I can upload data to mqtt.
I’ve assumed the migration, or at least the SPI connection would be transparent, but boy was I wrong.