Hitag support pages
Covered transponder family: PCF7937EA and it’s mcu based derivatives - e.g. PCF7x41ETT and PCF7x61ETT, widely used by GM (Opel, Chevrolet).
Security is based on 48-bit secret key, principles are very similar to basic Hitag2 (PCF7936) transponder operation. Main advantage is 512 byte EEPROM memory where additional data are stored.
XMA (extended memory access) is based on similar principles like HitagPro - 8 pages with individual access rights.
Blank chip must be configured first to grant XMA access.