What: /sys/class/spi_master/spi/spi./fram Date: June 2021 KernelVersion: 5.14 Contact: Jiri Prchal Description: Contains the FRAM binary data. Same as EEPROM, just another file name to indicate that it employs ferroelectric process. It performs write operations at bus speed - no write delays. What: /sys/class/spi_master/spi/spi./sernum Date: May 2021 KernelVersion: 5.14 Contact: Jiri Prchal Description: Contains the serial number of the Cypress FRAM (FM25VN) if it is present. It will be displayed as a 8 byte hex string, as read from the device. This is a read-only attribute.