U124 UNIT ID Crypto Authentication Unit m5Stack U124 UNIT ID Crypto Authentication Unit is a crypto coprocessor with hardware-based secure key storage, integrated with ATECC608B hardware cryptographic chip, using an I2C communication interface. The chip has a built-in 10Kb EEPROM for storing keys, certificates, data, consumption records, and security configurations. The configuration can be locked to prevent changes by restricting access to memory areas.