Embedded Linux System Design And Development

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Embedded Linux System Design And Development

• Introduction

• An Embedded system is a special purpose
  computer that is designed to perform very small
  sets of designated activities.
• In early days(around 1960) , They were used to
  control Electromechanical telephone Switches.
• The first Recognizable embedded system was the
  Apollo guidance computer developed by Charles
  Draper and his team.

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Embedded Linux System Design And Development

• Introduction (cot. )

• Today they are widely used to serve various
  purposes
• Network Equipments such as firewall, router ,
  switches.
• Consumer Equipment such as MP3 players , cell
  phones, PDAs, digital.
• Household appliances such as microwaves , washing
  machines, televisions .
• Mission-Critical systems such as satellites and
  flight controls.

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• Key factors that differentiate an embedded system
  from the desktop computer
• Embedded systems are usually cost sensitive.
• Most Embedded Systems have real time constraints.
• There are multitude CPU architectures that are
  used in embedded systems.
• Embedded systems employ application-specific
  processors. For example , the processor in our
  digital camera is specially tailored for image
  capturing and rendering.

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• Key factors that differentiate an embedded system
  from the desktop computer (cont.)
• Embedded systems have very few resources in terms
  of RAM , Rom or other I/O devices as compared to
  a desktop computer.
• Power management is an important aspect in most
  embedded systems.
• Embedded systems generally have an inbuilt
  circuitry for debugging purposes.
• An Embedded System is designed from both the
  hardware and software
• perspective, taken into account a specific
  application or set of applications.

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• HISTORY OF EMBEDDED LINUX
• Linus Benedict Torvalds at the University of
  Helsinki
• created the Linux Operating system in 1991.
• Under the GNU General Public License (GPL) ,
  Linux
• License is released. It has allowed all the
  source code
• to be freely available for personal or commercial
  use.

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• HISTORY OF EMBEDDED LINUX
• In early 1996, Michael Barabanov and Victor
  Yodaiken
• used Linux in real-time embedded systems as a
• research project. This RT-Linux research project
  was
• based on using a small real-time kernel along
  with
• Linux to provide real time deadline guarantees.
• Year 1999
• Linux started to develop its roots in Embedded
• Systems Area.
• Year 2000
• Many companies adopted Embedded Linux in their
• Product lines.

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HISTORY OF EMBEDDED LINUX (cont.) Year
2001 Release of Linux Kernel 2.4, which was later
adopted in many Embedded Linux Distributions.
Embedded Linux standardization efforts started
gaining ground. The Free Standard Group (FSG)
released Linux Standard Base (LSB)
specifications. In terms of tools and utilities
uClibc was made. uClibc now is an integral part
of almost all Embedded Linux distributions.

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HISTORY OF EMBEDDED LINUX (cont.) Year
2002 Release of Linux Kernel 2.4, which was later
adopted in many Embedded Linux Distributions.
Embedded Linux standardization efforts started
gaining ground. The Free Standard Group (FSG)
released Linux Standard Base (LSB)
specifications. In terms of tools and utilities
uClibc was made. uClibc now is an integral part
of almost all Embedded Linux distributions.

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HISTORY OF EMBEDDED LINUX (cont.) Year
2003 Linux saw its growth in the Cell phone and
Digital Entertainment Industry. Linux saw more
penetration in gateways, routers and wireless
LANs. Year 2004 Free Standard Group (FSG) and
Open Source Development Lab (OSDL) released
Linux Standard Base LSB 2.0
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• HISTORY OF EMBEDDED LINUX (cont.)
• Thus lots of companies are adopting Embedded
• Linux for their new designs.
• Various Vendors are providing Embedded
• Linux Distribution for various Hardware
  platforms.
• Silicon suppliers use Linux as a preferred
• hardware bring-up platform

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• Why Embedded Linux?
• Vendor Independence
• Time to Market
• Varied hardware Support
• Low Cost
• Development Cost
• Training and Hiring Cost
• Runtime Royalty

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• Why Embedded Linux? (cont.)
• Open Source
• POSIX Compliant APIs

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The End