1 <?xml version="1.0" encoding="utf-8"?>

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    10 <!DOCTYPE concept

    11   PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">

    12 <concept id="GUID-4AFDA3FF-38D1-5EFE-B18A-E3EAAA52EB75" xml:lang="en"><title>Flash

    13 Guide</title><shortdesc> Flash memory is a class of memory that can retain its contents

    14 even after the power has been switched off.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

    15 <section id="GUID-71F0C83A-D03C-5CF7-9395-C7BD746B25A8"><title>Introduction</title> <p>Unlike

    16 ROM, the data in Flash memory can be changed by an application. </p> </section>

    17 <section id="GUID-97937125-353C-4043-B430-0327E214C87B"><title>Flash memory features</title> <p>  Features of Flash memory

    18 are:</p><ul>

    19 <li><p> Writing and erasing of memory has to be undertaken in blocks of memory</p></li>

    20 <li><p> Memory contents are retained until erased (regardless of whether the

    21 power has been turned on/off). </p></li>

    22 </ul></section>

    23 <section id="GUID-70642797-8164-462D-9542-05E8CB343629"><title>Flash memory limitations</title> <p>The following are limitations

    24 of FLASH memory: </p><ul>

    25 <li><p>There are a finite number of erase-write cycles (usually 100,000).</p></li>

    26 <li><p>NAND Flash cannot be executed in place. Instead the contents have to

    27 be loaded into RAM and then executed. </p></li>

    28 </ul></section>

    29 </conbody></concept>