EEPROMFLASH.pdf

Rev. 0, 9/03

56F83xx Lends

Hybrid

Applications

EEPROM

Capability

FlashEE

White Paper

Motorola 56F8300

Hybrid Controller

Family

MOTOROLA.COM/SEMICONDUCTORS

56F83xx Lends Hybrid

Applications EEPROM

Capability -- FlashEE

John L. Winters

Contents

Introduction ........................................1

1.1 Overview .........................................1

1.2 The Keys to FlashEE....................... 2

1.3 How the Keys Open the Way.......... 2

Using the Keys -- FlashEE on a 56F3xx

Device ....................................... 2

2.1 A Program Illustrates the Concept .. 2

2.2 The Program Explained .................. 4

Conclusion .........................................8

References ..........................................8

1. Introduction

1.1 Overview

Motorola has introduced a new class of hybrid MCU/DSP

devices addressing the needs associated with automotive,

industrial, consumer, motor control and other system control

applications requiring Flash memory and EEPROM

capability. These devices are the 56F8322, 56F8323,

56F8345, 56F8346, 56F8356, and 56F8357 parts,

collectively referred to as the 56F83xx family.

This report presents the architectural advantage offered by

the 56F83xx family of devices with respect to using its

on-chip Flash as EEPROM. It also recounts the method used

to demonstrate this capability and displays some of the source

code.

Why use on-chip Flash as EEPROM?

A control system may be required to store a variety of

information, including control information, calibration data,

phone numbers, data logs, temperature exteme data,

maximum velocity data, boundry GPS coordinates, and many

other types of data. This data may need to be updated by the

control system autonomously, perhaps in the field of

deployment, and may be required for the system’s self-

calibration. The information stored may need to be retained,

even when power is not supplied to the device. In many

applications, an EEPROM is required to store non-volatile

data; it could be eliminated if the 56F83xx’s on-board Flash

could be used to store all of this data. Using Flash to replace

EEPROM has been named “FlashEE ” in a previous Motorola

Application Note (please see Reference 1).

Using the Keys -- FlashEE on a 56F3xx Device

1.2 The Keys to FlashEE

The keys to unlock FlashEE reside within the Flash memory subsystem of the 56F83xx family:

•

A minimum of up to 10K write/erase cycles across temperature range; up to 100K is typical

•

A data Flash Memory Page size of only 256 words

•

No special voltages are required for Flash programming

1.3 How the Keys Open the Way

The Motorola 56F83xx family includes all three keys. But what if just one of these keys is omitted?

• Omit the first key and it will wear out the Flash before the normal life cycle of the product

• Omit the second key and the number of data words used up each time any parameter must be

updated will soon cycle through all available memory, resulting in a linear decrease of product

life

For example, if the page size was 8K and only 256 words needed to be written at once, then

most of the 8K words would be wasted and the product life would decrease by a factor of 16 ,

assuming equal memory sizes.

• Omit the last key and special voltages would be needed just to update data in FlashEE

There’s no need to do without any of these keys, since they are all built into the Flash Memory

subsystem of the Motorola 56F83xx family of devices.

2. Using the Keys -- FlashEE on a 56F3xx Device

2.1 A Program Illustrates the Concept

The tested, working C program at the end of this section has been used to train engineers using

FlashEE on a 56F83xx controller. Section 2.2 discusses the operation of this program in detail.

By writing such a simple program, it’s easy to use as a seed for more complex applications requiring

FlashEE. It can be cut/pasted into an application, tested, then scaled up to the data structure to be

saved. Integration would then meld the FlashEE technique into the application. This is a stand-alone

example which uses simple subroutines.

This simple example just writes one 16-bit word to the Data FLASH using the FlashEE technique.

When a page finally fills up, it is not used again until it is erased. This example then shows how to save

the value of a 16-bit word in a non-volatile manner using the FlashEE technique.

Why FlashEE 16 bits and not just one bit at a time? Since both the row size and the word size are 16

bits, each word may be written only once prior to erasing. Thus, if only one bit is be stored, it would

have to be stored in a 16-bit word. Repeated writes to a word without an erase can damage the Flash,

since the specifications would be exceeded.

Code Example 1 is a part of a larger program, which is available with all source code, including

subroutines. See Reference 3.

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Motorola

Using the Keys -- FlashEE on a 56F3xx Device

Code Example 1.

/* Using Flash as EEPROM on 56F836 -- Training Module */

#include "ssd_types.h"

#include "ssd_hfm.h"

#include "ssd_hfm_config.h"

#include "ssd_demo.h"

#include "ssd_hfm_clk.h"

#include "clock.h"

#include <stdio.h>

#include <stdlib.h>

// Flash configuration stucture

FlashConfig flashConfig =

{

HFM_BASE,

HFM_CONFIG_BASE,

FLASH_CLOCK_DIVIDER,

false

};

UWord16 buffer[SOURCE_DATA_BUFFER_SIZE];

UWord16 main(void)

{

UWord16 Flash_bits; // as read from flash

UWord16 i; // Index

FLASH_TYPE flashType; // The type of flash block

UWord32 flashBaseAddr, // The base address of flash block

flashSize; // The size of flash block

UWord32 eraseBlkStartAddr; // The start address of flash block

UWord16 number; // Flash page number operation applicable

UWord32 source; // Source address for program and verify

UWord32 dest, // Flash start address operation applicable

size; // Flash size operation applicable

UWord32 Flash_p ; // Pointer to flash

// Set the vector base address

REG_WRITE(INTC_BASE_ADDRESS + INTC_VBA, 0x300);

// Set the PLL

SetPLL(PLL_PRESCALER, PLL_POSTSCALER, PLL_MULTIPLIER);

//=========================== Initialize HFM Module for Data Flash

===========================

FlashInit((UWord32)(&flashConfig));

flashType = FLASH_TYPE_D;

flashBaseAddr = DATA_FLASH_START_ADDR;

flashSize = DATA_FLASH_SIZE;

number = DATA_FLASH_SIZE / FLASH_PAGE_SIZE_D;

// Clear the all protect bits

FlashSetProtection((UWord32)(&flashConfig), flashType, 0x0000);

//=========================== Find unused flash word (=1)

===========================

for (Flash_p = DATA_FLASH_START_ADDR;

Flash_p < DATA_FLASH_START_ADDR + DATA_FLASH_SIZE;

Flash_p ++

) // if word is 0xfff it must be errased already:

MOTOROLA

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