PiFinger.PiFinger, the first-ever Fingerprint HAT for Raspberry Pi Comprise of onboard Nuvoton MCU with an on-chip crypto-accelerator, Cortex-M23 TrustZone, and XOM facilities. A user can use the communication protocol to the PiFinger with commands over the UART protocol with the Baud rate 115200 bps or USB 2.0 full speed.