Introduction to uCOS II v2 6 m1

Introduction to uCOS-II V2.6


About SwiftACT
• A Technology services startup company
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Under establishment

• Areas of specialties:
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Mobile telecommunication services development
Embedded systems development

• Types of services:
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o
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Consultation
Managed services
Sourcing
Training

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6

About Me
• Graduated 2004
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ECE, ASU: 5 yrs distinction

• 5+ years in embedded systems development
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SDLC, Apps, MW, DD, Porting, ...

• 3+ years in SW engineering
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PSP, CMMI, Systematic reuse, ...

• 3+ years in SW testing
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IBM certified, ISTQB certified, ...

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Copyright
• Materials in this course is the property of Amr Ali Abdel-Naby.
• Reproduction or transmission of the materials in any manner

without the copyright owner permission is a law violation.

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Course References
• MicroC/OS-II The Real-Time Kernel, 2nd Edition, by Jean J.
Labrosse

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Outline
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Introduction to µC/OS-II
Kernel Structure

Task Management
Time Management
Semaphore Management
Mutual Exclusion Semaphores
Event Flag Management
Message Mailbox Management
Message Queue Management
Memory Management

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Outline
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Introduction to µC/OS-II
Kernel Structure
Task Management
Time Management

Semaphore Management
Mutual Exclusion Semaphores
Event Flag Management
Message Mailbox Management
Message Queue Management
Memory Management

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


At the Beginning
• Written By J. Labrosse
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First published in 1992

• µC/OS-II is a trade mark of Micrium.
• It is pronounced as “micro C OS 2”.
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Not mucus 

• 1000s applications are using it all over the world.
• A good starting point to experience real-time OS
• Simple but yet very powerful

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


µC/OS-II in Literature
• Four books were published to explain the internals:
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“μC/OS The Real-Time Kernel”, in 1992
“μC/OS-II The Real-Time Kernel”, in 1998
“μC/OS-II The Real-Time Kernel”, Second Edition in 2002
“μC/OS-III The Real-Time Kernel”, in 2009

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


µC/OS-II History
µC/OS
V1.08

µC/OS-II
V2.00

µC/OS V1.08
+
Memory Manager

+
Stack Checking
+
CPU Load Checking

Amr Ali Abdel-Naby@2010

µC/OS-II
V2.52

µC/OS-II
V2.86

µC/OS-II V2.00
+
Safety Critical
+
Mutexes
+
Semaphores
+
Event Flags

µC/OS-II V2.52
+
Timers
+
250 Tasks
+
MMU & MPU

Introduction to uCOS-II V2.6

µC/OS-III

µC/OS-II V2.86
+
RR Scheduling
+
Infinite # of Tasks
&
Services


µC/OS-II Features
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Source code
Portable
Romable

Scalable
Preemptive
Multitasking
Deterministic
Task stack
Services
Interrupt management
Robust & reliable

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Source Code
• High quality
• Neat
• Consistent
• Organized
• Commented
• MISRA-C compliant

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Portable
• Highly portable ANSI C
• Assembly is kept minimum.

• Supports 8-, 16-, 32-, 64- bit
processors
• Ported over 100 different
processors
• All ports are freely available
at Micrium website.

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Romable
• If you have the proper tool chain, it can be embedded into your
system.
• No need for disks

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Scalable
• Use the service you only need.
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Very few services  Complete services available
A group of #defines determines scalability.

• Minimum footprint = 2 KB

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Preemptive
• Fully preemptive
• Always runs the highest priority task that is ready to run
• Comparable with other preemptive kernels

ISR

Task Y
Task X

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Multitasking
• Manages up to 64 tasks
• 8 tasks are used by µC/OS-II.
• 56 tasks are left to applications.
• A unique task/priority
• RR and FIFO are not supported.

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Deterministic
• You can always know how
much time μC/OS-II will take
to execute a service.
• Execution time is
independent of tasks running.
• The only exceptions are
OSTimeTick & some event
flag services.

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Task Stacks
• Each task has its stack.
• μC/OS-II allows different stack sizes.
• Stack checking utility
• You can determine & decide how much stack is needed for each
task.

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6

Services
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Semaphores
Mutexes
Event flags
Message queues
Mailboxes
Fixed size memory partitions
Task management
Time management

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Interrupt Management
• An interrupt can suspend a task execution.
• The highest priority ready task runs after serving the interrupt.
• Nested interrupts
o Up to 255 level

ISR

Task Y
Task X

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Robust & Reliable
• Used by many products
• Support
• Tested & certified in safety critical systems

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Related Products
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µC/Probe
µC/TCP-IP
µC/FS
µC/GUI
µC/USB
µC/CAN
µC/Modbus
µC/FL
µC/Building Blocks
µC/OSEK-VDX

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


µC/OS-II Market
• Distributors all over the word
• Huge customer list

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


License
• Educational
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Free
Universities
Non-profitable use

• Source Code
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If µC/OS will be distributed with your product as a source code

• Object Code
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If µC/OS will be distributed with your product as a binary

• Not royalty free

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6