1. Embedded System
Introduction

2. What is an embedded system?
Embedded systems (ES) = information
processing systems embedded into a
larger product

3. An embedded system is a computer
designed for specific control
functions within a
larger System.
It is embedded as a part of a complete
often including hardware and
mechnical part.
Embedded system contain processing
cores that are typically either Micro-
controllers or digital signal processors.

4. Embedded Systems Model
 What the Embedded Systems Model indicates
is that all embedded systems share one
simi-larity at the highest level; that is, they all
have at least one layer (hardware) or all layers
(hardware, system software and application
software) into which all components fall.
 The hardware layer contains all the major
physical components located on an embedded
board, whereas the system and application
software layers contain all of the software
located on and being processed by the
embedded system.

6. Embedded Systems Design
 When approaching embedded systems architecture design,
several models can be applied to describe the cycle of
embedded system design.
 The big-bang model: there is essentially no planning or
processes in place before and during the development of a
system.
 The code-and-fix model: product requirements are defined
but no formal processes are in place before the start of
development.
 The waterfall model: there is a process for developing a
system in steps, where results of one step flow into the next
step.
 The spiral model: there is a process for developing a system
in steps, and throughout the various steps, feedback is
obtained and incorporated back into the process.

8. Characteristics of Embedded Systems
 Must be dependable,
• Reliability R(t) = probability of system working
correctly provided that is was working at t=0
• Maintainability M(d) = probability of system working
correctly d time units after error occurred.
• Availability A(t): probability of system working at time t
• Safety: no harm to be caused
• Security: confidential and authentic communication
Even perfectly designed systems can fail if the assumptions
about the workload and possible errors turn out to be wrong.
Making the system dependable must not be an after-thought,
it must be considered from the very beginning

9. Must be efficient
–Energy efficient
–Code-size efficient
(especially for systems on a chip)
–Run-time efficient
–Weight efficient
–Cost efficient
Dedicated towards a certain application
Knowledge about behavior at design time can be used to
minimize resources and to maximize robustness
Dedicated user interface
(no mouse, keyboard and screen)
Hybrid systems (analog + digital parts).

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