Introduction to uCOS II v2 6 m10

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
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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•
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•
•
•
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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


Memory Management
• Fixed-size memory block management
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To prevent fragmentation

• Multiple partitions can be created with different sizes.
• Blocks allocated from certain partitions must be returned back to
the same partitions

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Memory Management cont’d

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Memory Management APIs
• Available memory operations are:
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Creating a memory partition
Obtaining a memory block
Returning a memory block
Obtaining status of a memory partition
Naming a memory partition
Getting the name of a memory partition

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Creating a Partition, OSMemCreate
• A partition must be created before used.

OS_MEM *CommTxBuf;
INT8U *CommTxPart[100][32];

void main(void){
...
CommTxBuf = OSMemCreate(CommTXPart, 100, 32, &err);
...
}

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Creating a Partition, OSMemCreate
cont’d
OS_MEM *OSMemCreate (void *addr, INT32U nblks, INT32U
blksize, INT8U *err)
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addr: The starting address of the memory partition
nblks: The number of memory blocks to create from the partition
blksize: The size (in bytes) of each block in the memory partition
err:
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No error
Invalid address
No available resources
Invalid number # blocks
Invalid block size

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Obtaining a Memory Block,
OSMemGet
void *OSMemGet (OS_MEM *pmem, INT8U *err)
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pmem: A pointer to the memory partition control block to get the block
from
err:
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o
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No error
No free blocks
PMEM is null.

Return value:
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Non-null for successful creation
Null for failure

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Naming a Memory Partition,
OSMemNameSet
void OSMemNameSet (OS_MEM *pmem, char *pname, INT8U *err)
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pmem: A pointer to the memory partition control block to give a name to
it
pname: A pointer to an ASCII string that contains the name
err:
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No error
pmem is null.

pname is null.
Long name

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Getting a Memory Partition Name,
OSMemNameGet
INT8U OSMemNameGet (OS_MEM *pmem, char *pname, INT8U
*err)
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pmem: A pointer to the memory partition control block to get its name
pname: A pointer to an ASCII string that will receive the name
err:
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o
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No error
pmem is null.
pname is null.

Return value: Name length

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Returning a Memory Block,
OSMemPut
INT8U OSMemPut (OS_MEM *pmem, void *pblk)
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pmem: A pointer to the memory partition control block that the block
belongs to
pblk: A pointer to the memory block being released
Return value:
o
o
o
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No error
Freeing more than allocation
pmem is null.
pblk is null.

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6

Obtaining Status of a Memory
Partition, OSMemQuery
INT8U OSMemQuery (OS_MEM *pmem, OS_MEM_DATA *pdata)
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pmem: A pointer to the desired memory partition control block
pdata: A pointer to the returned memory partition control block
information
Return value:
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o
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No error
pmem is null.
pdata is null.

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6


Waiting for Memory Blocks from a
Partition
• Waiting for memory blocks is not supported in µC/OS-II.
• It might be desirable to wait for memory blocks from a full

partition.
• Semaphores are here to help.
• Semaphores will guard the partition.

Amr Ali Abdel-Naby@2010

Introduction to uCOS-II V2.6