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

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

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

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

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

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

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

<p>However note that: </p>

<ul>

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

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

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

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

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

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

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

</ul>

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

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

kept for binary compatibility purposes. </p>

</conbody></concept>