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<concept id="GUID-A91C6359-E547-51AD-AA8C-45BCAFBA98AC" xml:lang="en"><title>Kernel
Architecture (EKA2)</title><shortdesc>EKA2 is the principal Hardware and Kernel Services module.
It manages the CPU and memory resources of a phone, and provides an
architecture for device drivers to manage other hardware resources. </shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>
<p id="GUID-B66850E3-11C9-58D6-ADB3-12ABBC1B792C"> The Kernel has
a layered architecture so that it can be ported to different hardware.
All base ports must implement a layer called the ASSP/Variant that
provides essential hardware-specific services for the Kernel. </p>
<p>The Kernel also allows additional layers called personality layers
to be created that provide emulations of traditional real time operating
systems. This allows applications that were written for those operating
systems to be run on Symbian platform. </p>
<p>The device driver architecture and the services that the Kernel
provides to device drivers are described in the <xref href="GUID-0437DB4C-FC4E-51DC-BB4C-95C0B26834F5.dita">Device Driver Guide</xref>. </p>
</conbody><related-links>
<link href="GUID-77DF7A6B-F01D-5B9F-9C7A-662A04ED8BE7.dita"><linktext>ASSP
  Kernel Extension Overview</linktext></link>
<link href="GUID-0437DB4C-FC4E-51DC-BB4C-95C0B26834F5.dita"><linktext>Device
  Driver Guide</linktext></link>
<link href="GUID-C06CFF3E-23E9-5E0B-99A1-51B8ED95465F.dita"><linktext>USB
Client   Driver</linktext></link>
<link href="http://developer.symbian.org/wiki/index.php/Symbian_OS_Internals/1._Introducing_EKA2" scope="external"><linktext>Symbian OS Internals - Chapter 1 Introducing
EKA2</linktext></link>
<link href="http://developer.symbian.org/wiki/index.php/Symbian_OS_Internals/2._Hardware_for_Symbian_OS" scope="external"><linktext>Symbian OS Internals - Chapter 2 Hardware
for Symbian OS</linktext></link>
<link href="http://developer.symbian.org/wiki/index.php/Symbian_OS_Internals/5._Kernel_Services" scope="external"><linktext>Symbian OS Internals - Chapter 5 Kernel
Services</linktext></link>
<link href="http://developer.symbian.org/wiki/index.php/Symbian_OS_Internals/7._Memory_Models" scope="external"><linktext>Symbian OS Internals - Chapter 7 Memory
Model</linktext></link>
</related-links></concept>