September 2013

Rev

2

1/17

AN2244

Application note

EEPROM emulation with ST10F27x embedded Flash

using the ST10F27x Flash library

Introduction

The ST10F27x MCUs provide 0.18µm embedded true Flash technology.

This Flash technology has been designed to store software program instructions and is not

adapted to dynamic data storage because it can only be erased by sector.

Typically, when the code is programmed, some portions of the Flash remain free. This

unused space can be used as virtual EEPROM, thus avoiding the additional cost and

complexity incurred by using an external serial EEPROM.

This application note shows a method of performing EEPROM emulation. It provides

software routines to overcome the Flash limitations in terms of read/write access and

number of cycles.

This document is divided into the following sections:

become familiar with the ST10F27x Flash library, given that it uses the main important

Flash library functions of programming, erasing and verifying.

The application source files are provided within an associated downloadable package. This

file must be unpacked into a directory before use.

The EEPROM emulation driver was compiled using the two tool chains, Tasking and Keil,

and it can be ported easily to any other ST10 tool chain.

For more information, please refer to the ST10F27x related documentation.

www.st.com