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Freescale Semiconductor
Application Note
Document Number: AN3615
Rev. 0, 03/2008
Contents
© Freescale Semiconductor, Inc., 2008. All rights reserved.
1 Background and
Overview
This document is intended to serve as an additional
reference for the EEPROM on the MC9S08DZ and
MC9S08DN family of microcontrollers. Much of what is
contained is applicable to most of Freescale’s HCS08
microcontrollers that contain embedded EEPROM.
Various applications and implementations of EEPROM,
with regard to automotive applications, will be
discussed. Application and usage of EEPROM as well as
strategies specific to the MC9S08DZ microcontroller
will be presented at a hardware and software level.
1 Background and Overview . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 New S08 Technology . . . . . . . . . . . . . . . . . . . . . . . 2
1.2 EEPROM Uses and Applications . . . . . . . . . . . . . . 2
1.3 Types of EEPROM Devices . . . . . . . . . . . . . . . . . . 3
1.4 EEPROM Arrangement . . . . . . . . . . . . . . . . . . . . . . 5
2 Applications and Usage of EEPROM . . . . . . . . . . . . . . . 8
2.1 Determining Application Requirements . . . . . . . . . . 8
2.2 Extending EEPROM Life . . . . . . . . . . . . . . . . . . . . 9
3 Simple Programming Through the Command Interface 13
3.1 State Machine Command Interface . . . . . . . . . . . . 13
3.2 State Machine Commands . . . . . . . . . . . . . . . . . . 14
4 Additional Strategies for Protecting EEPROM Data
Integrity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.1 Loss of Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.2 MCU Bus Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.3 Software Runaway . . . . . . . . . . . . . . . . . . . . . . . . 19
5 Conclusion/Summary . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Design Considerations for
Implementing EEPROM using the
MC9S08DZ60
by: Jesse Beeker
Lydia Ziegler
Field Applications Engineering
Detroit Automotive Technical Center
