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    10 <!DOCTYPE concept

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

    12 <concept id="GUID-0B23D1B5-3EE1-5874-8605-5C48CB4690F2" xml:lang="en"><title>HAL

    13 (Hardware Abstraction Layer)</title><shortdesc/><prolog><metadata><keywords/></metadata></prolog><conbody>

    14 <p>The structure of the HAL has not changed between EKA1 and EKA2, but you

    15 may still need to make some changes. </p>

    16 <p>Groups are new, and the HAL handler functions have changed. The location

    17 of Config files and Values files, the signatures and the behavioural requirements

    18 of accessor functions for derived attributes have <i>not</i> changed. </p>

    19 <p>However note that: </p>

    20 <ul>

    21 <li id="GUID-4D737F65-0556-50EE-9356-DF147761298F"><p>the implementation of

    22 existing EKA1 HAL handler functions may need changing to conform with the

    23 general coding changes required by EKA2; see <xref href="GUID-43BC99CA-9D60-557C-A43C-99EF1D6E4ECF.dita">Important

    24 Changes between EKA1 and Kernel Architecture 2</xref>. </p> </li>

    25 <li id="GUID-B2343591-DEB5-5953-992C-8E81031E8BD2"><p>it should rarely be

    26 necessary to write accessor functions for derived attributes, as all likely

    27 functions are already implemented in <filepath>...\hal\src\userhal.cpp</filepath>. </p> </li>

    28 </ul>

    29 <p>The functions <codeph>UserSvr::HalGet()</codeph> and <codeph>UserSvr::HalSet()</codeph> are

    30 no longer used. They now return <xref href="GUID-F89DA3F0-2A48-3F9B-8F08-29350E92D0E4.dita"><apiname>KErrNotSupported</apiname></xref> and are

    31 kept for binary compatibility purposes. </p>

    32 </conbody></concept>