11.4 Flash Memories

This devices comes with a 512 KB Program Flash Memory (PFM), a 16 KB Boot Flash Memory (BFM), and a 32 KB Configuration Flash memory (CFM). They all support ECC for correcting on the fly ECC errors or detecting double errors.

Program and Boot Flash Memory (PFM and BFM)

Refer to the Chapter 31 Non-Volatile Memory Controller for details about Programming, Erasing, Reading these memories.

Configuration Flash Memory (CFM)

The CFM contains the following pages:

  • CALOTP: This page contains read only calibration values. Some values need to be copied by the application software in ADC, PTC or USB before these peripherals can be used.
  • VSS0/1: Two Variable Slot Storage for storing security assets.
  • ROMCFG: This page contains:
    • The PUF Activation Code (AC)
    • The Debug Access Level (DAL) value
    • The tamper log
    • The Boot ROM interactive mode command keys and locks
    • Pre-boot configuration settings for running MBIST on Boot or Boot ROM CRC
  • BOOTCFG1/1A: These pages contain the boot configuration selected by the user and applied by the ROM code. They must contain the same duplicate information. The ROM code will automatically switch from one to the other in case of errors found.
  • USEROTP: 1 page dedicated for user application. It could be used to store a serial number, some user defined keys, or custom analog calibration values, and so on. Once written, each row can be locked independently forever, refer to FCW.UOWP for additional information. Once protected and locked, it cannot be erased using a page erase or chip erase.