Introduction to uCOS II v2 6 m3

Introduction to uCOS-II V2.6 About SwiftACT • A Technology services startup company o Under establishment • Areas of specialties: o o Mobile telecommunication services development Embedded systems development • Types of services: o o o o Consultation Managed services Sourcing Training Amr Ali Abdel-Naby@2010 Introduction to uCOS-II V2.6 About Me • Graduated 2004 o ECE, ASU: yrs distinction • 5+ years in embedded systems development o SDLC, Apps, MW, DD, Porting, • 3+ years in SW engineering o PSP, CMMI, Systematic reuse, • 3+ years in SW testing o 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 • • • • • • • • • • 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 • • • • • • • • • • 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 Task Management APIs • Available task operations are: o o o o o o o o o Task creation Stack checking Task deletion Requesting a task deletion Changing a task’s priority Task suspension Task resumption Getting task’s info Task name manipulation Amr Ali Abdel-Naby@2010 Introduction to uCOS-II V2.6 Creating a Task, OSTaskCreate INT8U OSTaskCreate (void (*task)(void *pd), void *pdata, OS_STK *ptos, INT8U prio) • • • • • task: A pointer to the task's code pdata: A pointer to an optional data area which can be used to pass parameters to the task when the task first executes ptos: A pointer to the task's top of stack prio: The task's priority Return value: o o o No error Priority exist Invalid priority Amr Ali Abdel-Naby@2010 Introduction to uCOS-II V2.6 Creating a Task, OSTaskCreateExt INT8U OSTaskCreateExt (void (*task)(void *pd), void *pdata, OS_STK *ptos, INT8U prio, INT16U id, OS_STK *pbos, INT32U stk_size, void *pext, INT16U opt) • • • • • • OSTaskCreate + id: Task’s ID, not used currently pbos: A pointer to the task's bottom of stack stk_size: A pointer to the task's top of stack pext: A pointer to a user supplied memory location which is used as a TCB extension opt: Additional information (or options) about the behavior of the task Amr Ali Abdel-Naby@2010 Introduction to uCOS-II V2.6 Task Stacks • Each task has its own stack o It must be:  Declared as OS_STK  Consistent & contiguous memory • It can be allocated static • Or dynamic OS_STK MyTaskSTack[stack_size]; OS_STK *pstk; pstk = (OS_STK*)malloc(stack_size); Amr Ali Abdel-Naby@2010 Introduction to uCOS-II V2.6 Task Stacks cont’d • Dynamic allocation may suffer from fragmentation KB A (1KB) (1KB) B (1KB) B (1KB) C • Your code should support(1KB) stacks that(1KB) grow in either direction OS_STK TaskStack[stack_size]; #ifdef OS_STK_GROWTH == OSTaskCreate(task, pdata, &TaskStack[0], prior); #else OSTaskCreate(task, pdata, &TaskStack[stack_size-1], prior); #endif Amr Ali Abdel-Naby@2010 Introduction to uCOS-II V2.6 Stack Checking • Assume stack is cleared at the beginning Amr Ali Abdel-Naby@2010 Introduction to uCOS-II V2.6 Stack Checking, OSTaskStkChk INT8U OSTaskStkChk (INT8U prio, OS_STK_DATA *pdata) • • • prio: The task priority pdata: A pointer to stack data Return value: o o o o No error Invalid priority Task does not exist Task options does not support stack checking Amr Ali Abdel-Naby@2010 Introduction to uCOS-II V2.6 Deleting a Task, OSTaskDel INT8U OSTaskDel (INT8U prio) • • prio: Priority of the task to delete Return value: o o o o o No error Invalid priority Task does not exist Deleting idle task Deleting a task from ISR Amr Ali Abdel-Naby@2010 Introduction to uCOS-II V2.6 Requesting to Delete a Task • A deleted task should delete its resources as well o To avoid leaks • The OSTaskDelReq is the keyword void RequestorTask(void * pdata){ if(TasktoBeDeleted needs to be deleted){ while(OSTaskDelReq(Task_TO_DEL_PRIO) != OS_TASK_NOT_EXIST) OSTimeDly(1); } void TaskToBeDeleted(void * pdata){ } if(OSTaskDelReq(OS_PRIO_SELF) == OS_TASK_DEL_REQ){ Release any resources & de-allocate any dynamic memory; OS_DEL(OS_PRIO_SELF); } else{ /* Application code*/ } } Amr Ali Abdel-Naby@2010 Introduction to uCOS-II V2.6 Requesting to Delete a Task, OSTaskDelReq INT8U OSTaskDelReq (INT8U prio) • • prio: Priority of the task to be deleted Return value: o o o o o No error Invalid priority Task does not exist Deleting idle task Deleting a task from ISR Amr Ali Abdel-Naby@2010 Introduction to uCOS-II V2.6 Changing a Task’s Priority, OSTaskChangePrio INT8U OSTaskChangePrio (INT8U oldprio, INT8U newprio) • • • oldprio: The old priority newprio: The new priority Return value: o o o o o No error Invalid priority Task to change priority does not exist New priority already exists Changing IDLE priority Amr Ali Abdel-Naby@2010 Introduction to uCOS-II V2.6 Resuming a Task, OSTaskResume INT8U OSTaskResume (INT8U prio) • • prio: The priority of the task to resume Return value: o o o o No error Invalid priority Task is not suspended Task does not exist Amr Ali Abdel-Naby@2010 Introduction to uCOS-II V2.6 Suspending a Task, OSTaskSuspend INT8U OSTaskSuspend (INT8U prio) • • prio: The priority of the task to suspend Return value: o o o o No error Invalid priority Suspending idle task Task does not exist Amr Ali Abdel-Naby@2010 Introduction to uCOS-II V2.6 Getting Info About a Task, OSTaskQuery INT8U OSTaskQuery (INT8U prio, OS_TCB *pdata) • • • prio: The priority of the task to obtain its information pdata: A pointer to returned task information Return value: o o o No error Invalid priority Task does not exist Amr Ali Abdel-Naby@2010 Introduction to uCOS-II V2.6 Getting a Task’s Name, OSTaskNameGet INT8U OSTaskNameGet (INT8U prio, char *pname, INT8U *err) • • • prio: The priority of the task that you want to obtain its name pname: A pointer to an ASCII string that will receive the name of the task err: o o o o • No error Task does not exist A null pointer is passed for the name Invalid priority Return value: Length of the string Amr Ali Abdel-Naby@2010 Introduction to uCOS-II V2.6 Naming a Task, OSTaskNameSet void OSTaskNameSet (INT8U prio, char *pname, INT8U *err) • • • prio: The priority of the task that you want to assign a name to pname: A pointer to an ASCII string that contains the name of the task err: o o o o o No error Task does not exist Name too long A null pointer is passed for the name Invalid priority Amr Ali Abdel-Naby@2010 Introduction to uCOS-II V2.6 [...]... Abdel-Naby@2010 Introduction to uCOS- II V2. 6 Deleting a Task, OSTaskDel INT8U OSTaskDel (INT8U prio) • • prio: Priority of the task to delete Return value: o o o o o No error Invalid priority Task does not exist Deleting idle task Deleting a task from ISR Amr Ali Abdel-Naby@2010 Introduction to uCOS- II V2. 6 Requesting to Delete a Task • A deleted task should delete its resources as well o To avoid leaks... priority Task to change priority does not exist New priority already exists Changing IDLE priority Amr Ali Abdel-Naby@2010 Introduction to uCOS- II V2. 6 Resuming a Task, OSTaskResume INT8U OSTaskResume (INT8U prio) • • prio: The priority of the task to resume Return value: o o o o No error Invalid priority Task is not suspended Task does not exist Amr Ali Abdel-Naby@2010 Introduction to uCOS- II V2. 6 Suspending... pdata, &TaskStack[stack_size-1], prior); #endif Amr Ali Abdel-Naby@2010 Introduction to uCOS- II V2. 6 Stack Checking • Assume stack is cleared at the beginning Amr Ali Abdel-Naby@2010 Introduction to uCOS- II V2. 6 Stack Checking, OSTaskStkChk INT8U OSTaskStkChk (INT8U prio, OS_STK_DATA *pdata) • • • prio: The task priority pdata: A pointer to stack data Return value: o o o o No error Invalid priority Task... Abdel-Naby@2010 Introduction to uCOS- II V2. 6 Naming a Task, OSTaskNameSet void OSTaskNameSet (INT8U prio, char *pname, INT8U *err) • • • prio: The priority of the task that you want to assign a name to pname: A pointer to an ASCII string that contains the name of the task err: o o o o o No error Task does not exist Name too long A null pointer is passed for the name Invalid priority Amr Ali Abdel-Naby@2010 Introduction. .. RequestorTask(void * pdata){ if(TasktoBeDeleted needs to be deleted){ while(OSTaskDelReq(Task _TO_ DEL_PRIO) != OS_TASK_NOT_EXIST) OSTimeDly(1); } void TaskToBeDeleted(void * pdata){ } if(OSTaskDelReq(OS_PRIO_SELF) == OS_TASK_DEL_REQ){ Release any resources & de-allocate any dynamic memory; OS_DEL(OS_PRIO_SELF); } else{ /* Application code*/ } } Amr Ali Abdel-Naby@2010 Introduction to uCOS- II V2. 6 Requesting... Return value: o o o No error Invalid priority Task does not exist Amr Ali Abdel-Naby@2010 Introduction to uCOS- II V2. 6 Getting a Task’s Name, OSTaskNameGet INT8U OSTaskNameGet (INT8U prio, char *pname, INT8U *err) • • • prio: The priority of the task that you want to obtain its name pname: A pointer to an ASCII string that will receive the name of the task err: o o o o • No error Task does not exist... prio) • • prio: The priority of the task to suspend Return value: o o o o No error Invalid priority Suspending idle task Task does not exist Amr Ali Abdel-Naby@2010 Introduction to uCOS- II V2. 6 Getting Info About a Task, OSTaskQuery INT8U OSTaskQuery (INT8U prio, OS_TCB *pdata) • • • prio: The priority of the task to obtain its information pdata: A pointer to returned task information Return value:... Amr Ali Abdel-Naby@2010 Introduction to uCOS- II V2. 6 Requesting to Delete a Task, OSTaskDelReq INT8U OSTaskDelReq (INT8U prio) • • prio: Priority of the task to be deleted Return value: o o o o o No error Invalid priority Task does not exist Deleting idle task Deleting a task from ISR Amr Ali Abdel-Naby@2010 Introduction to uCOS- II V2. 6 Changing a Task’s Priority, OSTaskChangePrio INT8U OSTaskChangePrio... OS_STK  Consistent & contiguous memory • It can be allocated static • Or dynamic OS_STK MyTaskSTack[stack_size]; OS_STK *pstk; pstk = (OS_STK*)malloc(stack_size); Amr Ali Abdel-Naby@2010 Introduction to uCOS- II V2. 6 Task Stacks cont’d • Dynamic allocation may suffer from fragmentation 3 KB A (1KB) (1KB) B (1KB) B (1KB) C • Your code should support(1KB) stacks that(1KB) grow in either direction OS_STK... ASCII string that contains the name of the task err: o o o o o No error Task does not exist Name too long A null pointer is passed for the name Invalid priority Amr Ali Abdel-Naby@2010 Introduction to uCOS- II V2. 6