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SVTH: VnQucDng

L Quang V

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CONTENT

Tng quan1

Task v Co-routine2

Inter-task Communication3

Soft-timer4

Support Architecture5

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TNG QUAN

FreeRTOSTMhtrchnh thc27 kin trc(PIC32, AVR32,)

Portable, open source, mini Real TimeKernel

C thsdng trong cc ngdngthngmi? -> GPL (General Public License)

http://www.freertos.org/open-source-software.htmlhttp://www.freertos.org/open-source-software.htmlhttp://www.freertos.org/open-source-software.htmlhttp://www.freertos.org/open-source-software.htmlhttp://www.freertos.org/open-source-software.htmlhttp://www.freertos.org/open-source-software.htmlhttp://www.freertos.org/open-source-software.htmlhttp://www.freertos.org/open-source-software.htmlhttp://www.freertos.org/open-source-software.htmlhttp://www.freertos.org/open-source-software.html

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TNG QUAN

OpenRTOSTM : fully featured professionalgrade USB, file system and TCP/IPcomponents

SafeRTOSTM : sdng trong safety criticalapplications

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TNG QUAN

Thitknhgn, dsdng. (4K to 9Kbytes).

Ngn nglp trnh C.Sdngtasks and co-routines.

http://www.freertos.org/taskandcr.htmlhttp://www.freertos.org/taskandcr.htmlhttp://www.freertos.org/taskandcr.htmlhttp://www.freertos.org/taskandcr.htmlhttp://www.freertos.org/taskandcr.htmlhttp://www.freertos.org/taskandcr.html

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TNG QUAN

Queues, binary semaphores, countingsemaphores, recursive semaphores andmutexes cho giao tip v ngbgia cc

task,v gia cc task v interrupt.Mutexesvipriority inheritance.Htrsoftware timers.

http://www.freertos.org/Inter-Task-Communication.htmlhttp://www.freertos.org/Inter-Task-Communication.htmlhttp://www.freertos.org/Inter-Task-Communication.htmlhttp://www.freertos.org/Inter-Task-Communication.htmlhttp://www.freertos.org/RTOS-software-timer.htmlhttp://www.freertos.org/RTOS-software-timer.htmlhttp://www.freertos.org/Inter-Task-Communication.htmlhttp://www.freertos.org/Inter-Task-Communication.htmlhttp://www.freertos.org/Inter-Task-Communication.htmlhttp://www.freertos.org/Inter-Task-Communication.html

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TASK V CO-ROUTINE

Task: Ready

Running

Block

Suspended

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TASK V CO-ROUTINE

Task: Multitaskingwith full preemption

Fully prioritised

Each task maintains its own stack

Priority: 0 -> configMAX_PRIORITIES1

Low -> High

= 0 : idle task

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TASK V CO-ROUTINE

Implement task:void vATaskFunction( void *pvParameters )

{

for( ;; )

{

-- Task application code here.

}

}

Create: xTaskCreate()Delete : vTaskDelete()

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TASK V CO-ROUTINE

Idle task: created automatically when the scheduler

is started

free memory allocated which will execute only when there are

no other tasks able to do

Other tasks can share the idle taskpriority

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TASK V CO-ROUTINE

Idle task:

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TASK V CO-ROUTINE

Share a single stackCo-routine:

Running

Ready

Block

Priority: 0 -> configMAX_CO_ROUTINE_PRIORITIES - 1

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TASK V CO-ROUTINE

Implement co-routine:void vACoRoutineFunction( xCoRoutineHandle

xHandle, unsigned portBASE_TYPE uxIndex )

{crSTART( xHandle );

for( ;; ) {

-- Co-routine application code here.

}

crEND();

}

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TASK V CO-ROUTINE

Scheduling co-routine: scheduled by repeated calls to

vCoRoutineSchedule()

tasks and co-routines to be easily mixed withinthe same application

execute when there are no tasks of priority higher

than the idle task

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INTER-TASKCOMMUNICATION

Queues

Binary SemaphoresCounting Semaphores

Mutexes, and

Recursive Mutexes.

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INTER-TASKCOMMUNICATION

Queues

L dng chnh trong inter-taskcommunication.

Taskstasks, tasksinterrupts.

Thng c dng dng FIFO.

Phn t trong queue c kch thc c nh: c

th dng con tr nu cn thit. C 3 trng thi trng, y v bnh thng.

Ticks.

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INTER-TASKCOMMUNICATION

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INTER-TASKCOMMUNICATION

Binary Semaphores

Ch yu dng vi mc ch ng b.

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INTER-TASKCOMMUNICATION

Counting Semaphores

m s kin Semaphoes khi to l 0.

Khi c s kin Semaphore tng . Khi task nhn s kin Semaphore gim.

Qun l ti nguyn Semaphoes khi to l s lng ti nguyn.

Khi task ly ti nguyn th Semaphore gim.

Khi task tr ti nguyn th Semaphore tng.

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INTER-TASKCOMMUNICATION

Mutexes ('MUT'ual 'EX'clusion) Dng gii quyt ng .

Thay i priority cho ph hp.

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INTER-TASKCOMMUNICATION

Recursive Mutexes

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SOFTWARE TIMERS

In a nutshellOne-Shot and Auto-reload

Resetting a Timer

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SOFTWARE TIMERS

In a nutshell Gi hm ti mt thi im xc nh trong

tng lai.

NOTE: Software timers phi c khi totrc khi s dng.

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SOFTWARE TIMERS

One-Shot and Auto-reload

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SOFTWARE TIMERS

Resetting a Timer

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SUPPORT ARCHITECTUREAlteraAtmelCortusCypressEnergy MicroFreescale

FujitsuLuminary MicroMicrochipNECMicrosemi (formally Actel)NXPRenesasSilicon LabsST MicroelectronicsTexas InstrumentsXilinxx86 (real mode)x86 / Windows Simulator

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SUPPORT ARCHITECTURE

the PIC32, a MIPS based 32bit microcontroller offerings from Microchip

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SUPPORT ARCHITECTURE

he TCP/IP demo uses the lwIP TCP/IP stack and includes a basicweb and TFTP server implementation

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