Introduction to Real Time Embedded Systems

7/28/2019 Introduction to Real Time Embedded Systems

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Lecture Plan

Program Information:

Program organization

Recommended literature

Introduction to RT embedded systems

What is an RT Embedded System

RT Embedded Systems Design Industry and

Applications


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Course Organization


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Time, Location etc

1. Lectures days and time:

Every Thursday

From 18.00 to 22.00 (be at time)

2. Course duration - ~6 months [bruto], about 250 ac. Hours(frontal and for the project design).

3. Address: Ramat Gan, 7 Aba Hilel str., floor 15

1. Parking for free options: Yazira and Ahaliav str. (100-200m fromCDC)


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Programs Grades Structure

Final grade structure:

Project 40% from the semester grade

Each project includes the Design Specs and the DesignEnvironment

Exam 60% from the semester grade

Each exam is in American Style (multiple choice) and closed books

The minimum required exams and projects grade is: 65.

The required course average is: 70.


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Study and Help with Job Search Plan

The Course milestones are the Project milestones: MRD, Kickoff, PDR, CDR, FDR and final exam

CV Design - Very effective and professional help

Coaching for successful career building Time and project management

Career planning and Job search plan design.

Project FDR with Senior Designers from High Tech companies Diploma, Recommendations and Individual meetings for successful jobsearch etc: CV/Linkedin Profile Design

Job search plan design

Technical Interview Simulation


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Course rules

Work with slides questions, comments

Study environment at home

Weekly Back up

Course Forum

Documents and code style Design reviews and final submission.

Homework assignments, which will be done individually or in groups.

** The main target of the course is making the students mature enough in VLSI

Design for the industry. Help yourself using internet forums and onlinedocumentation.

** Students get certificate if stand successfully in course requirements.

- Every one will get the tools for working from home, plus 1 evaluation boardfor design group.


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Evaluation Board for Real Project design


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Ev. Board for Real Project design cont.


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Copyright 2005 AVMBrothers Ltd.

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Semester A Firmware Design

(RT Emb. Systems Design)

Introduction to the Program:- Program fundamentals: rules, material and work environment

- Embedded systems market overview and Job search planning

Introduction to RT Embedded Systems:

- RT Embedded Systems Overview real time constrains- Design Process- Requirements and Specifications- Architecture Design

Embedded System Architecture

- Modern Embedded Systems Architecture Overview- CISC/RISC/DSP Processors Overview (Focused on ARM)

Memory System and I/O sub-system Architectures- Bus Protocols Organization (AMBA, APB, AHB, etc.)

Programming Embedded Systems

- C for RT Emb. Design Brief on Programming language at real time environment- Introduction to Compile and Debug tools

- Source control and Bug tracking tools overview


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Semester A (part2) Firmware Design

Designing Embedded Computing Platform- Boot programming- Memory Devices and their Characteristics- RAM, ROM, UVROM, EEPROM, DRAM, FLASH- I/O Devices/ Timers and Counters- Clock management (PLL/CPLD, oscillators)- IC/DMA/IR Devices-A/D,D/A, Serial/Parallel interfaces

Reference RT Embedded System Design Project Overview.First RT Embedded System Design Project Start: Kick off and PDR (Preliminary Design Review)

RT Emb. Working Environment

- Development Environment and Basic IDE concepts- Projects management and Workspaces

- Manufacturing and Testing

Coaching Part 1: Life targets and career planning

Ref RT Emb. Project Code Review- Program Design- Design Patterns for Embedded Systems emphasis on specific issues for RT- Models of Program- Control and Data flow Graph- Programming and Run-time Environment- Analysis and Optimization of Execution Time/Energy, Power/Program Size

- Program Validation and TestingFirst RT Embedded Design Project Design Reviews: CDR and FDR (Critical and Final Design Reviews).

Semester A exam RT Embedded Designer Evaluation Exam (Basic Stage).


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Semester B Emb. Systems Design with Emb. Linux

CPU and HW overview

- Support for various processors (ARM, MIPS etc) by Linux.

Registers, busses, interrupts, memory subsystem

Linux introduction, system calls

- Overview of Linux; GPL; userspace code uses kernel services

Processes, threads

- Process concept; lifetime; implementation, stacks; usage; priorities

RT vs. others Synchronization and IPC (inter-process communication)

Context switch, scheduler

Interrupts subsystem

Memory subsystem/Non-volatile memory


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Semester B(Part2) Emb. Systems Design with Emb. Linux

Filesystems

- i-node. Embedded filesystems: JFFSx, YAFFS, UBIFS, ROMFS, CRAMFS, NFS,PROCFS

Networking

- Layers and protocols; internet-enabled systems; network-enabled applications

Introduction to Linux system administration - Creating development environment; setting NFS, TFTP, samba, NFS servers

Drivers

- Character device drivers; kernel modules; kernel busses

Reference Advanced RT Emb. Design Project Overview.

Advanced RT Emb. Design Project Implementation: MRD, Kick off , PDR, CDR, FDR Coaching Part 2:

- Project Schedule and CV Design + interview preparation

Practical part for the Network Based Embedded Applications

Program Final exam: Embedded Real-Time Designer Evaluation Exam (Final Program

Exam).


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Course Material

Course Material includes:

Slide Sets 4 books: (2 for SemA - Firmware, 2 for SemB Emb. Linux)

1. Introduction to RT Embedded Systems Design:

1. RT Embedded Design Technologies and Design Flow

2. Structure of Modern Processors, Peripherals.2. Projects review and design:

1. Main rules for the design, RT programming with ASM and C.

2. RT Emb. System Design: Ref Project Review and help to the FirstProject Design

3. Introduction to RTOS VxWorks and Embedded Linux.

4. Design in OS environment and Advanced Ref Project review + designthe First Project with RTOS.

Reference RT Embedded Design and Advanced RT Embedded DesignProjects Design Environment - Soft Copy.


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Recommended Literature

1. Computer Systems

Computer System Architecture, Moris Mano (ISBN-13:

9780131755635)

The Indispensable PC Hardware Book Hans Peter Messmer(ISBN: 0-201-59616-4)

2. RT Embedded Design

- "Real time UML: Developing Efficient Objects for Embedded

Systems" by Bruce Powel Douglass

3. Programming with C and ASM

- C Traps & Pitfalls - Andrew Koenig


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Recommended Literature

4. Real Time Operating System Programming

Real-Time Embedded Multithreading Using ThreadX and ARM

Edward L. Lamie

Building Embedded Linux Systems

Karin Yaghnmour

Real-Time Concepts for Embedded SystemsQing Li,Caroline Yao


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What is a Real Time

Embedded System?


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Embedded System Design introduction

Real Time System Example:

A telephone switching system must feed dial tone to thousands ofsubscribers within a recommended limit of one second

The off hook detection mechanism and the software messagecommunication involved have to work within the limited timebudget

The system has to meet these requirements for all the calls being setup at any given time


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Introduction to RT Emb. Sys. - Industry and Applications

Microprocessor Market Share all embedded almost


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What Is a Real Time ?

Definition: AnEmbedded system is a computer system designed to perform

one or a few dedicated functions. It is embeddedas part of a complete device

often including hardware and mechanical parts .For example, your IPOD is an embedded system.

Definition: AReal Time Application is an application which has time

constrains. This is a pre-defined operational deadlines from event to system

response, the time must be met even if the system runs at full load (worse casescenario).For example, a car engine control system is a real-time system because a delayed signal may causeengine failure or damage.


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Real Time System

System is described as beingdeterministic if its response time is

predictable

Lag time between the occurrence of an event and response to that

event is called latency

Deterministic response is key to real-time performance


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Hard vs. Soft Real Time

Hard real-time means all hard deadlines are always met

Each event, like a button push, will be processed and completed at

a predefined time, regardless of system load

Time

Event Event processed and completed (Max.)Guaranteed worst-case response times


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Soft real-time means that event tolerate lateness, and may respond with

decreased service quality

For example, Video player may lose some frames while playing a video

Time

Event The CPU will allocate the bandwidth toprocess the event, there is no guaranteeof completion time


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Hard Real Time is necessary for critical missions such as heart

pacemaker and industrial process controllers, where failure to

meet a guaranteed response time could lead to catastrophic results.

In Soft Real Time users are happier when the system responds

optimally, but which is not considered to have "failed" when the

system doesn't meet each and every desired response time.On average, a soft real-time system meets a particular response

time goal.


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RT system is dealing with solving real time constrains:

Real time Response The system needs an immediate response can even be in

magnitude order nano-seconds

Asynchronous events can occur at any time


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Race Conditions and Timing

Buffers zone limited size needs timed treatment

Mutual demand for resources


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Size limitation

System on Chip or Board tends to be very limited in space -

This forces many limitation on the processor in terms of

address lines number etc

Power consumption

The power budget is very limited and extremely importantespecially in mobile applications


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Performance

The system performance is a key issue and must be kept in allcircumstance

Performance is a major factor in choosing the processor, the clock

frequency , ram size , code size etc..

Re-use

In many projects the system relies on already developed components,which the designer must reuse. These components already have

embedded constrains in addition to the new system constraints.

Recovering from Failures

Working in a distributed environment connection failure


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SoC System On Chip

The System On Chip consists of a few different block typesinside the same chip like:

CPU The main processor unit

Memory devices Volatile and non-volatile

Internal bus interfaces and decoders

Peripheral devices

Digital/Analog functions


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SoB System On Board Full set of the necessary devices as standalone on the same

board:

CPU The main processor unit

Memory devices Volatile and non-volatile Internal bus interfaces and decoders

Peripheral devices


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RT Embedded Technologies


Platforms types: Firmware (SoC/SoB)

RTOS

Drivers technology


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The firmware systems

About 25% of the system are without OS

The OS mechanism is not a must for this kind of usuallysimple application

Rom part

Ram part

Interrupts part

Exceptions part

Firmware Software

CPU

Peripherals

RAM

Firmware

System Blocks - Overview


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Firmware systems main features

- Small code size 5-100k Using only procedure level

programming

- Main Loop system

- Drivers for communication and/or peripheral devices can

hold a major part of the system

- The firmware can manage and control a single SOC, or cancontrol also devices on a full Board level


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System with RTOS (Real Time Operating Systems) features:

- Medium & Large code size 100k - 4m per processor

- A system can hold several processors- Using all programming levels

- RTOS includes :

time base task scheduling mutual exclusion treatment

task priority

etc


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What Is An Operating System (1 of 2)

An Operating System (OS) is a computer program that

manages the hardware and software resources of a computer

Operating system performs basic tasks such as:

Controlling and allocating memory

Prioritizing system requests

Controlling input and output devices

Facilitating networking

Managing files

In other words, it forms a platform for other software.

What Is Operating System (2 of 2)


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What Is Operating System (2 of 2)

Real Life Examples

Controlling and allocating memory

When you launch you favorite computer game memory is

allocated for the games variables.

Prioritizing system requests

The eject button in a fighter has higher priority than the

lights management system

Controlling input and output devices

Network Interface Card (NIC) connect your computer to theinternet


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System with RTOS (Continue)

Drivers for communication and/or peripheral devices usuallyhold a minor part of the system

The system with RTOS can reside on a system on chip (SOC)

or on a System On Board (SOB) at a full Board level


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Introduction to Device Drivers

What are device drivers?

Make the attached device work

Insulate the complexities involved in I/O handling

Application

Device driver

Hardware

RTOS

D i E l


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Drivers Examples


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RT Embedded Device Drivers

Device Driver Characterization

Device Drivers Functionalities

initialization

data access

data assignment

interrupt handling

E b dd d S t D i i t d ti


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RT system Programming languages

Old systems - include many parts in assembly language -

processor dependent language

Current systems - most real time systems are based on RTOSnow, written in the C language. Still, for crucial time tasks,

Assembly code may be required (e.g when cycle count is

important).

Some applications which have a lot of software - less real

time oriented , but application business dependent , or which

inherited software base - are written using C++

Many application have several programming languagesmixed due to real time constrains or inherited code



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ASM language

The assembly language is processor dependent

No reuse to other processors

Mastered by a limited number of programmers

Has all the known limitation of assembler :

One C line on average 5 assembly commands

Very hard to check and debug Very efficient in terms of execution time and code size



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C language Is NOT processor dependent

Reuse to other processor is very common

Known to a very large number of programmers

Relatively easy to check and debug Quite efficient in terms of execution time and code size

The compiler can include optimizers for using the processor pipeline structureefficiently

C++ language C++ language is NOT processor dependent

Reuse to other processor is extremely common

Known to a very large number of programmers

Medium effort require for testing and debug

NOT efficient in terms of execution time and code size

E b S t I d t d A li ti


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Emb. Systems Industry and Applications

CPUs for RT Emb. Systems

Cellular market:

ARM

Marvell

Toshiba


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RT Emb. Systems Industry and Applications

Communication market:

Power PC- Motorola

8051 Intel

MIPS

ARM

ARC

XSCALE


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Industry and Applications


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Industry and Applications

Job Market Sectors in Israel Semiconductors Intel, IBM, Freescale, Applied,

Orbotech

Communication Cisco, Rad, ECI, NDS.- Each of the above has 100s of RT- embedded engineers

Security Elbit, IAI, Rafael, Nice, Verint

Most of the above has 1000s of RT Embedded engineers

There are many medium size companies and plenty of small

ones

Introduction to RT Emd Systems - Industry and Applications


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Introduction to RT Emd. Systems - Industry and Applications

Israel - Salary Survey Oct-2009 - software

30-4026-3023-2818-2415-19Embedded

Systems

Designer

Senior MngJunior

Mng/Team

Leader

6+ years3-5 years0-2 yearsFunction