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# 1.3.1 Emulated EEPROM

The use of FLASH memory technology over EEPROM presents several difficulties over true EEPROM memory; data must be written as a number of physical memory pages (of several bytes each) rather than being individually byte addressable, and entire rows of FLASH must be erased before new data may be stored. To help abstract these characteristics away from the user application an emulation scheme is implemented to present a more user-friendly API for data storage and retrieval.

This module provides an EEPROM emulation layer on top of the device's internal NVM controller, to provide a standard interface for the reading and writing of non-volatile configuration data. This data is placed into the EEPROM emulated section of the device's main FLASH memory storage section, the size of which is configured using MHC.

There are many different algorithms that may be employed for EEPROM emulation using FLASH memory, to tune the write and read latencies, RAM usage, wear levelling and other characteristics. As a result, multiple different emulator schemes may be implemented, so that the most appropriate scheme for a specific application's requirements may be used.