uC/OS-II (Structure) - 경희대학교

MicroC/OS
/OS-II
Structure
Embedded System Lab. II

Contents
• Introduction
• Kernel Structure
• Task Management
• Time Management
• Event Control Block
• Semaphore Management
• Mutual Exclusive Semaphore
• Event Flags Management
• Message Mail Box Management
• Message Queue Management
• Memory Management
• MicroC/OS-II Porting
Embedded System Lab. II 1

Introduction
Embedded System Lab. II

Introduction
• MicroC/OS-II
1992 Jean J. Labrosse
, .
:
: http://www.ucos-ii.com( )
‣ .
Embedded System Lab. II 3

Introduction (Cont’d)
• MicroC/OS-II Multitasking Preemptive Real time Kernel
• MicroC/OS-II 64 .
, 4 56 Task
OS_LOWEST_PRIO
.
• Portable
ANSI-C ,
.
8Bit, 16Bit, 32Bit 64Bit, DSP Porting .
• Realiable
-
• Romable
• Scalable
‣ FAA(Federal Aviation Administration) .(2000 7)
Embedded System Lab. II 4

Introduction (Cont’d)
• -
• .
–
‣
(TCP/IP GUI )
•
• , , Mailbox, Queue, Semaphore, Memory partition
•
.
(up to 255 levels deep)
•
Embedded System Lab. II 5

Kernel Structure
Embedded System Lab. II

Kernel Structure
uC/OS-II File Structure
Embedded System Lab. II 7

Kernel Structure (Cont’d)
OS_ENTER_CRITICAL()
OS_EXIT_CRITICAL()
OSInit()
OSStart()
OSIntEnter()
OSIntExit()
OSSchedLock()
OSSchedUnlock()
OS_SCHED_LOCK_EN
OS_SCHED_LOCK_EN
OSVersion()
Embedded System Lab. II 8

Kernel Structure (Cont’d)
• Critical Section, OS_ENTER_CRITICAL() & OS_EXIT_CRITICAL()
MicroC/OS-II OS_ENTER_CRITICAL() OS_EXIT_CRITICAL()
Interrupt
OS_ENTER_CRITICAL() OS_EXIT_CRITICAL() Critical Section
.
OS_ENTER_CRITICAL();
/* uC/OS-II critical code section */
OS_EXIT_CRITICAL();
.
OS_ENTER_CRITICAL() OS_EXIT_CRITICAL()
.
(OS_CPU.H OS_CRITICAL_METHOD )
‣ 1.OS_ENTER_CRITICAL() OS_EXIT_CRITICAL() /
‣ 2. / Stack
‣ 3. C
Embedded System Lab. II 9

Kernel Structure (Cont’d)
• Task – Infinite loop function
MicroC/OS-II Task 64 .
MicroC/OS-II 8 Idle, CPU Task
.(ex. 1 -> )
Task Task .
void YourTask (void *pdata)
{
for (;;){
/* USER CODE */
Call one of uC/OS-II’s services:
OSFlagPend();
OSMboxPend();
OSMutexPend();
OSQPend();
OSSemPend();
OSTaskDel(OS_PRIO_SELF);
OSTaskSuspend(OS_PRIO_SELF);
OSTimeDly();
OSTimeDlyHMSM();
/* USER CODE */
}
}
Embedded System Lab. II 10

Kernel Structure (Cont’d)
• Task
Embedded System Lab. II 11

Kernel Structure (Cont’d)
• Task Control Block
Task Task Task control block OS_TCB .
OS_TCB RAM .
‣ OSTCBStkPtr : Task .
• .
• .
‣ OSTCBStat : Task , ucos.c
‣ OSTCBDly : Task timeout
.
‣ OSTCBX, OSTCBY, OSTCBBitX, OSTCBBitY : Task
‣ OSTCBNext, OSTCBPrev : OS_TCB .
‣ OSTCBEventPtr : Event control block
Embedded System Lab. II 12

Kernel Structure (Cont’d)
• Task Control Block
typedef struct os_tcb {
OS_STK *OSTCBStkPtr; /* Pointer to current top of stack */
#if OS_TASK_CREATE_EXT_EN > 0
void *OSTCBExtPtr; /* Pointer to user definable data for TCB */
OS_STK *OSTCBStkBottom; /* Pointer to bottom of stack */
INT32U OSTCBStkSize; /* Size of task stack (in number of stack) */
INT16U OSTCBOpt; /* Task options as passed by OSTaskCreateExt() */
INT16U OSTCBId; /* Task ID (0..65535) */
#endif
struct os_tcb *OSTCBNext; /* Pointer to next TCB in the TCB list */
struct os_tcb *OSTCBPrev; /* Pointer to previous TCB in the TCB list */
#if ((OS_Q_EN > 0) && (OS_MAX_QS > 0)) || (OS_MBOX_EN > 0) || (OS_SEM_EN > 0) ||
(OS_MUTEX_EN > 0)
OS_EVENT *OSTCBEventPtr; /* Pointer to event control block */
#endif
#if ((OS_Q_EN > 0) && (OS_MAX_QS > 0)) || (OS_MBOX_EN > 0)
void *OSTCBMsg;
/* Message received from OSMboxPost() or OSQPost()
#endif
Embedded System Lab. II 13

Kernel Structure (Cont’d)
• Task Control Block
#if (OS_VERSION >= 251) && (OS_FLAG_EN > 0) && (OS_MAX_FLAGS > 0)
#if OS_TASK_DEL_EN > 0
OS_FLAG_NODE *OSTCBFlagNode; /* Pointer to event flag node */
#endif
OS_FLAGS OSTCBFlagsRdy; /* Event flags that made task ready to run */
#endif
INT16U OSTCBDly;
/* Nbr ticks to delay task or, timeout waiting for event
INT8U OSTCBStat; /* Task status */
INT8U OSTCBPrio;
/* Task priority (0 == highest, 63 == lowest)*/
INT8U OSTCBX; /* Bit position in group corresponding to task priority (0..7) */
INT8U OSTCBY; /* Index into ready table corresponding to task priority */
INT8U OSTCBBitX; /*Bit mask to access bit position in ready table */
INT8U OSTCBBitY; /*Bit mask to access bit position in ready group */
#if OS_TASK_DEL_EN > 0
BOOLEAN OSTCBDelReq; /* Indicates whether a task needs to delete */
#endif
} OS_TCB;
Embedded System Lab. II 14

Kernel Structure (Cont’d)
• Task Control Block
OSTCBNext
OSTCBNext
OSTCBNext
OSTCBNext
OSTCBNext
OSTCBNext
OSTCBNext
[0] 0
[1] 0
[2] 0
[3] .
.
[61]
[62]
[63]
0
OSTCBHighRdy
OSTCBCur
ptcb
OSTCBList
0
OS_TCB OS_TCB OS_TCB
OSTCBNext OSTCBNext OSTCBNext
OSTCBPrev OSTCBPrev OSTCBPrev
OSTCBFreeList
OS_TCB OS_TCB OS_TCB
OSTCBNext OSTCBNext OSTCBNext
Embedded System Lab. II 15

Kernel Structure (Cont’d)
• Ready List
OSRdyGrp OSRdyTbl[ ] Ready Task
ready Task
OSRdyGrp
‣ Task
‣ 8 (Task ID)
‣ OSRdyGrp Ready
OSRdyTbl[ ]
‣ Ready
Embedded System Lab. II 16

Kernel Structure (Cont’d)
• Ready List
Embedded System Lab. II 17

Kernel Structure (Cont’d)
•
OSRdyGrp |= OSMapTbl[prio >> 3];
OSRdyTbl[prio >> 3] |= OSMapTbl[prio & 0x07];
•
if((OSRdyTbl[prio>>3] &= ~OSMapTbl[prio & 0x07]) == 0)
OSRdyGrp &= ~OSMapTbl[prio >> 3];
•
y = OSUnMapTbl[OSRdyGrp];
x = OSUnMapTbl[OSRdyTbl[y]];
prio = (y

Kernel Structure (Cont’d)
• Ready List
Embedded System Lab. II 19

Kernel Structure (Cont’d)
• Task Scheduling
MicroC/OS-II Task
Task Scheduling OS_Sched() .
ISR Scheduling OSIntExit() .
void OS_Sched (void)
{
#if OS_CRITICAL_METHOD == 3
OS_CPU_SR cpu_sr;
#endif
INT8U y;
}
OS_ENTER_CRITICAL();
if ((OSIntNesting == 0) && (OSLockNesting == 0)) {
y = OSUnMapTbl[OSRdyGrp];
OSPrioHighRdy = (INT8U)((y

Kernel Structure (Cont’d)
• Task Context Switching
OS_TASK_SW()
Task
Embedded System Lab. II 21

Kernel Structure (Cont’d)
Task
void OSCtxSw (void)
{
PUSH R1, R2, R3 and R4 onto the current stack;
OSTCBCur->OSTCBStkPtr = SP;
OSTCBCur = OSTCBHighRdy;
SP = OSTCBHighRdy->OSTCBStkPtr;
POP R4, R3, R2 and R1 from the new stack;
Execute a return from interrupt instruction;
}
Embedded System Lab. II 22

Kernel Structure (Cont’d)
• Scheduler /
OSSchedLock() OSSchedUnlock() Scheduler .
MicroC/OS-II 255 Scheduling .
OSLockNesting 0 Scheduler .
void OSSchedLock (void)
{
#if OS_CRITICAL_METHOD == 3
OS_CPU_SR cpu_sr;
#endif
}
if (OSRunning == TRUE) {
OS_ENTER_CRITICAL();
if (OSLockNesting < 255) {
OSLockNesting++;
}
OS_EXIT_CRITICAL();
}
Embedded System Lab. II 23

Kernel Structure (Cont’d)
• Scheduler /
void OSSchedUnlock (void)
{
#if OS_CRITICAL_METHOD == 3
OS_CPU_SR cpu_sr;
#endif
}
if (OSRunning == TRUE) {
OS_ENTER_CRITICAL();
if (OSLockNesting > 0) {
OSLockNesting--;
if ((OSLockNesting == 0) && (OSIntNesting == 0)) {
OS_EXIT_CRITICAL();
OS_Sched();
} else {
OS_EXIT_CRITICAL();
}
} else {
OS_EXIT_CRITICAL();
}
}
Embedded System Lab. II 24

Kernel Structure (Cont’d)
• Idle Task / OS_TaskIdle()
MicroC/OS-II Idle Task .
Idle Task Task .
Idle Task (OS_LOWEST_PRIO) .
Idle Task .
void OS_TaskIdle (void *pdata)
{
#if OS_CRITICAL_METHOD == 3
OS_CPU_SR cpu_sr;
#endif
}
pdata = pdata;
for (;;) {
OS_ENTER_CRITICAL();
OSIdleCtr++;
OS_EXIT_CRITICAL();
OSTaskIdleHook();
}
Embedded System Lab. II 25

Kernel Structure (Cont’d)
• Task / OS_TaskStat()
MicroC/OS-II .
OS_CFG.H OS_TASK_STAT_EN 1 Task
Task CPU 1 % .
Task Task Task
.
void main (void)
{
OSInit(); /* Initialize uC/OS-II */
/* Install uC/OS-II's context switch vector */
/* Create your startup task (for sake of discussion, TaskStart()) */
OSStart(); /* Start multitasking */
}
void TaskStart (void *pdata)
{
/* Install and initialize uC/OS-II’s ticker */
OSStatInit(); /* Initialize statistics task */
/* Create your application task(s) */
for (;;) {
/* Code for TaskStart() goes here! */
}
}
Embedded System Lab. II 26

Kernel Structure (Cont’d)
• Task
Embedded System Lab. II 27

Kernel Structure (Cont’d)
• Task / OSStatInit()
OSStatInit() Idle Task
Idle (OSIdleCtr) .
void OSStatInit (void)
{
#if OS_CRITICAL_METHOD == 3
OS_CPU_SR cpu_sr;
#endif
}
OSTimeDly(2);
OS_ENTER_CRITICAL();
OSIdleCtr = 0L;
OS_EXIT_CRITICAL();
OSTimeDly(OS_TICKS_PER_SEC);
OS_ENTER_CRITICAL();
OSIdleCtrMax = OSIdleCtr;
OSStatRdy = TRUE;
OS_EXIT_CRITICAL();
Embedded System Lab. II 28

Kernel Structure (Cont’d)
• Task
void OS_TaskStat (void *pdata)
{
#if OS_CRITICAL_METHOD == 3
OS_CPU_SR cpu_sr;
#endif
INT32U run;
INT32U max;
INT8S usage;
pdata = pdata;
while (OSStatRdy == FALSE){
OSTimeDly(2 *
OS_TICKS_PER_SEC);
}
max = OSIdleCtrMax / 100L;
}
for (;;) {
OS_ENTER_CRITICAL();
OSIdleCtrRun = OSIdleCtr;
run = OSIdleCtr;
OSIdleCtr = 0L;
OS_EXIT_CRITICAL();
if (max > 0L) {
usage = (INT8S)(100L - run / max);
if (usage >= 0) {
OSCPUUsage = usage;
} else {
OSCPUUsage = 0;
}
} else {
OSCPUUsage = 0;
max = OSIdleCtrMax / 100L;
}
OSTaskStatHook();
OSTimeDly(OS_TICKS_PER_SEC);
}
Embedded System Lab. II 29

Kernel Structure (Cont’d)
• MicroC/OS-II Interrupt
MicroC/OS-II Interrupt Service Routine (ISR)
C Inline C ISR
.
Interrupt
‣ OSIntEnter(), OSIntExit(), OSIntCtxSW()
YourISR:
Save all CPU registers;
Call OSIntEnter() or, increment OSIntNesting directly;
if (OSIntNesting == 1) {
OSTCBCur->OSTCBStkPtr = SP;
}
Clear interrupting device;
Re-enable interrupts (optional)
Execute user code to service ISR;
Call OSIntExit();
Restore all CPU registers;
Execute a return from interrupt instruction;
Embedded System Lab. II 30

Kernel Structure (Cont’d)
• MicroC/OS-II Interrupt
Embedded System Lab. II 31

Kernel Structure (Cont’d)
• Clock Tick / OSTimeTick()
MicroC/OS-II Clock Tick
Multitasking OSStart() Clock Tick
Interrupt .
Clock Tick
‣ OSTimeTick(), OSTickISR()
void OSTickISR(void)
{
Save processor registers;
Call OSIntEnter() or increment OSIntNesting;
if (OSIntNesting == 1) {
OSTCBCur->OSTCBStkPtr = SP;
}
Post a 'dummy' message (e.g. (void *)1) to the tick mailbox;
}
Call OSIntExit();
Restore processor registers;
Execute a return from interrupt instruction;
Embedded System Lab. II 32

Kernel Structure (Cont’d)
• MicroC/OS-II
MicroC/OS-II OSInit()
OSInit() MicroC/OS-II
OS_CFG.H #define
.
‣ OS_TASK_STAT_EN 1
‣ OS_FLAG_EN 1
‣ OS_LOWEST_PRIO 63
‣ OS_MAX_TASKS 62
Embedded System Lab. II 33

Kernel Structure (Cont’d)
• MicroC/OS-II
Embedded System Lab. II 34

Kernel Structure (Cont’d)
• MicroC/OS-II
Embedded System Lab. II 35

Kernel Structure (Cont’d)
• MicroC/OS-II
void main (void)
{
OSInit(); /* Initialize uC/OS-II */
.
.
Create at least 1 task using either OSTaskCreate() or OSTaskCreateExt();
.
.
OSStart(); /* Start multitasking! OSStart() will not return */
}
void OSStart (void)
{
INT8U y;
INT8U x;
if (OSRunning == FALSE) {
y = OSUnMapTbl[OSRdyGrp];
x = OSUnMapTbl[OSRdyTbl[y]];
OSPrioHighRdy = (INT8U)((y

Kernel Structure (Cont’d)
• MicroC/OS-II
Embedded System Lab. II 37

Task Management
Embedded System Lab. II

Task Management
• Task Management
Task
. ,
.
void YourTask (void *pdata)
{
for (;;) {
/* USER CODE */
Call one of uC/OS-II's services:
OSFlagPend();
OSMboxPend();
OSMutexPend();
OSQPend();
OSSemPend();
void YourTask (void *pdata)
{
/* USER CODE */
OSTaskDel(OS_PRIO_SELF);
}
}
}
OSTaskSuspend(OS_PRIO_SELF);
OSTimeDly();
OSTimeDlyHMSM();
/* USER CODE */
Embedded System Lab. II 39

Task Management (Cont’d)
• Task / OSTaskCreate() or OSTaskCreateExt()
Task Multitasking ,
Multitasking .
Multitasking (OSStart() ),
Task .
) Interrupt Service Routine Task .
OSTaskCreate( void (*task) (void *pd), void *pdata, OS_STK *ptos, INT8U
prio )
‣ : Task
‣ : Task
‣ : Task Stack
‣ : Task
OSTaskCreateExt() 9,
.
Embedded System Lab. II 40

Task Management (Cont’d)
• Task / OSTaskCreate() or OSTaskCreateExt()
INT8U OSTaskCreate (void (*task)(void *pd),
void *pdata, OS_STK *ptos, INT8U prio)
{
#if OS_CRITICAL_METHOD == 3
OS_CPU_SR cpu_sr;
#endif
void *psp;
INT8U err;
#if OS_ARG_CHK_EN > 0
if (prio > OS_LOWEST_PRIO) {
return (OS_PRIO_INVALID);
}
#endif
OS_ENTER_CRITICAL();
if (OSTCBPrioTbl[prio] == (OS_TCB *)0) {
OSTCBPrioTbl[prio] = (OS_TCB *)1;
OS_EXIT_CRITICAL();
psp = (void *)OSTaskStkInit(task, pdata, ptos, 0);
err = OS_TCBInit(prio, psp, (void *)0, 0, 0, (void *)0, 0);
if (err == OS_NO_ERR) {
OS_ENTER_CRITICAL();
OSTaskCtr++;
OS_EXIT_CRITICAL();
if (OSRunning == TRUE) {
OS_Sched();
}
} else {
OS_ENTER_CRITICAL();
OSTCBPrioTbl[prio] = (OS_TCB *)0;
OS_EXIT_CRITICAL();
}
return (err);
}
OS_EXIT_CRITICAL();
return (OS_PRIO_EXIST);
}
Embedded System Lab. II 41

Task Management (Cont’d)
• Task Stack
Task Stack , OS_STK
.
Stack ( ) ()
.
static OS_STK MyTaskStack[stack_size];
OS_STK MyTaskStack[stack_size];
Static Stack
OS_STK *pstk;pstk = (OS_STK *)malloc(stack_size);
if (pstk != (OS_STK *)0) { /* Make sure malloc() has enough space */
Create the task;
}
Using malloc() to allocate stack space for a task
Embedded System Lab. II 42

Task Management (Cont’d)
• Task Stack
Stack C malloc()
(Fragmentation)
A (1Kb)
Free(1Kb)
Free heap
(3Kb)
B (1Kb)
B (1Kb)
C (1Kb)
Free(1Kb)
A, C
( )
Embedded System Lab. II 43

Task Management (Cont’d)
• Task Stack
(OS_STK_GROWTH = 0)
OS_STK TaskStk[TASK_STK_SIZE];
OSTaskCreate(task, pdata, &TaskStk[0], prio);
(OS_STK_GROWTH = 1)
OS_STK TaskStk[TASK_STK_SIZE];
OSTaskCreate(task, pdata, &TaskStk[TASK_STK_SIZE-1], prio);
,
OS_STK TaskStk[TASK_STK_SIZE];
#if OS_STK_GROWTH == 0
OSTaskCreate(task, pdata, &TaskStk[0], prio);
#else
OSTaskCreate(task, pdata, &TaskStk[TASK_STK_SIZE-1], prio);
#endif
Embedded System Lab. II 44

Task Management (Cont’d)
• Stack / OSTaskStkChk()
Task Stack
Stack
‣ prio :
‣ pdata : OS_STK_DATA .
,
(uCOS_II.H )
Embedded System Lab. II 45

Task Management (Cont’d)
• Stack / OSTaskStkChk()
Embedded System Lab. II 46

Task Management (Cont’d)
• Task / OSTaskDelReq()
Task ,
Task OSTaskDelReq()
.
‣ prio
:
void RequestorTask (void *pdata)
{
INT8U err;
pdata = pdata;
for (;;) {
/* Application code */
if ('TaskToBeDeleted()' needs to be deleted) {
while (OSTaskDelReq(TASK_TO_DEL_PRIO) != OS_TASK_NOT_EXIST) {
OSTimeDly(1);
}
}
/* Application code */
}
}
Task
Embedded System Lab. II 47

Task Management (Cont’d)
• Task / OSTaskDelReq()
OSTaskDel()
‣ : Idle Task ,
‣ OS_TCB
• Ready list
• MailBox, Queue, Semaphore OS_TCB
‣ 0 : Task tick ISR
‣ OSTCBStat OS_STAT_RDY
‣ TCB OSTaskDelHook()
‣ Task
‣ OS_TCB
•
• OSTCBList OS_TCB
• free OS_TCB list OS_TCB
‣ : OSTaskDel() ISR
Embedded System Lab. II 48

Task Management (Cont’d)
• Task / OSTaskDelReq()
void TaskToBeDeleted (void *pdata)
{
INT8U err;
pdata = pdata;
for (;;) {
/* Application code */
if (OSTaskDelReq(OS_PRIO_SELF) == OS_TASK_DEL_REQ) {
Release any owned resources;
De-allocate any dynamic memory;
OSTaskDel(OS_PRIO_SELF);
} else {
/* Application code */
}
}
}
Task
Embedded System Lab. II 49

Task Management (Cont’d)
• Task / OSTaskChangePrio()
Run Time .
‣ Oldprio:
‣ Newprio:
‣ Task ready list Task
ready list .
‣ Task
.
‣ Task event waiting list
waiting list .
‣ Task OS_TCB OSTimeTick()
.
‣ enabled OS_TCB OSTCBX, OSTCBBitX, OSTCBY, OSTCBBitY
.
Embedded System Lab. II 50

Task Management (Cont’d)
• Task / OSTaskSuspend()
‣ prio:
OSTaskSuspend()
‣ Task Idle
‣ Task priority
‣ Task Ready List
‣ OS_TCB OS_STAT_SUSPEND .
‣ .
Embedded System Lab. II 51

Task Management (Cont’d)
• Task / OSTaskResume()
‣ prio:
OSTaskResume()
‣ Task Idle
‣ OSTCBStat (OS_TCB) OS_STAT_SUSPEND
‣ OSTCBDly 0 : Task
Task Task .
Embedded System Lab. II 52

Task Management (Cont’d)
• Task / OSTaskQuery()
Task
‣ prio:
‣ Pdata:
void MyTask (void *pdata)
{
OS_TCB MyTaskData;
}
pdata = pdata;
for (;;) {
/* User code */
err = OSTaskQuery(10, &MyTaskData);
/* Examine error code .. */
/* User code */
}
Embedded System Lab. II 53

Time Management
Embedded System Lab. II

Time Management
• Time Management
Time management configuration constants in OS_CFG.H.
uC/OS-II Time Management Service
Enabled when set to 1 in OS_CFG.H
OSTimeDly()
OSTimeDlyHMSM()
OS_TIME_DLY_HMSM_EN
OSTimeDlyResume()
OS_TIME_DLY_RESUME_EN
OSTimeGet()
OS_TIME_GET_SET_EN
OSTimeSet()
OS_TIME_GET_SET_EN
Embedded System Lab. II 55

Time Management (Cont’d)
• Task / OSTimeDly()
Clock tick(1~65535)
.
OSTimeDlyResume() .
‣ Ticks: Clock tick
Embedded System Lab. II 56

Time Management (Cont’d)
• Task / OSTimeDly()
Embedded System Lab. II 57

Time Management (Cont’d)
• Task / OSTimeDlyHMSM()
(H), (M), (S), (m)
.
uC/OS-II 256 .
OS_TIME_DLY_HMSM_EN == 1 . (OS_CFG.H)
‣ Hours:
‣ Minutes:
‣ Seconds:
‣ Milli:
Embedded System Lab. II 58

Time Management (Cont’d)
• Task / OSTimeDlyResume()
Task
, Task
Task .
65,535 .
.
OS_TIME_DLY_RESUME_EN == 1
‣ prio: Taks
Embedded System Lab. II 59

Time Management (Cont’d)
• / OSTimeGet(), OSTimeSet()
MicroC/OS-II Clock Tick Interrupt 32bit
OSStart() 0
, 4,294,967,295 Tick 0 .
OSTimeGet(): .
OSTimeSet(): .
Embedded System Lab. II 60

Event Control Block
Embedded System Lab. II

Event Control Block
• Event Control Block
Task ISR Event Control Block(ECB) Kernel Object
Task .
Embedded System Lab. II 62

Event Control Block (Cont’d)
• Event Control Block Structure
typedef struct {
INT8U OSEventType; /* Event type */
INT8U OSEventGrp; /* Group for wait list */
INT16U OSEventCnt; /* Count (when event is a semaphore) */
void *OSEventPtr; /* Ptr to message or queue structure */
INT8U OSEventTbl[OS_EVENT_TBL_SIZE]; /* Wait list for event to occur */
} OS_EVENT;
Embedded System Lab. II 63

Event Control Block (Cont’d)
• Wait List
Embedded System Lab. II 64

Event Control Block (Cont’d)
• Wait List Operation
Making a task wait for an event.
pevent->OSEventGrp |= OSMapTbl[prio >> 3];
pevent->OSEventTbl[prio >> 3] |= OSMapTbl[prio & 0x07];
Removing a task from a wait list.
if ((pevent->OSEventTbl[prio >> 3] &= ~OSMapTbl[prio & 0x07]) == 0) {
pevent->OSEventGrp &= ~OSMapTbl[prio >> 3];
}
Finding the highest priority task waiting for the event.
y = OSUnMapTbl[pevent->OSEventGrp];
x = OSUnMapTbl[pevent->OSEventTbl[y]];
prio = (y

Event Control Block (Cont’d)
• Wait List Example
Embedded System Lab. II 66

Event Control Block (Cont’d)
• List of Free ECBs
Embedded System Lab. II 67

Event Control Block (Cont’d)
• Event Control Block / OS_EventWaitListInit()
Semaphore, Mutex, Mailbox, Message Queue
.
Event Control Block Task
.
void OS_EventWaitListInit (OS_EVENT *pevent)
{
INT8U *ptbl;
pevent->OSEventGrp = 0x00;
ptbl = &pevent->OSEventTbl[0];
#if OS_EVENT_TBL_SIZE > 0
*ptbl++ = 0x00;
#endif
#if OS_EVENT_TBL_SIZE > 1
*ptbl++ = 0x00;
#endif
#if OS_EVENT_TBL_SIZE > 2
*ptbl++ = 0x00;
#endif
#if OS_EVENT_TBL_SIZE > 3
*ptbl++ = 0x00;
#endif
#if OS_EVENT_TBL_SIZE > 4
*ptbl++ = 0x00;
#endif
#if OS_EVENT_TBL_SIZE > 5
*ptbl++ = 0x00;
#endif
#if OS_EVENT_TBL_SIZE > 6
*ptbl++ = 0x00;
#endif
#if OS_EVENT_TBL_SIZE > 7
*ptbl = 0x00;
#endif
}
Embedded System Lab. II 68

Event Control Block (Cont’d)
• Task / OS_EventTaskRdy()
Event Control Block Task
Task .
• Task / OS_EventTaskWait()
Task MicroC/OS-II ,
Event Control Block .
• Task / OS_EventTO()
.
OSTimeTick() Task , OSSemPend(),
OSMboxPend(), OSQPend() .
Embedded System Lab. II 69

Semaphore Management
Embedded System Lab. II

Semaphore Management
• Semaphore Management
Semaphore configuration constants in OS_CFG.H
uC/OS-II Semaphore Service
OSSemAccept()
Enabled when set to 1 in OS_CFG.H
OS_SEM_ACCEPT_EN
OSSemCreate()
OSSemDel()
OS_SEM_DEL_EN
OSSemPend()
OSSemPost()
OSSemQuery()
OS_SEM_QUERY_EN
Embedded System Lab. II 71

Semaphore Management (Cont’d)
• Task, ISR, Semaphore
Embedded System Lab. II 72

Semaphore Management (Cont’d)
• Semaphore / OSSemCreate()
Semaphore , 0 ~ 65535
Semaphore .
Semaphore
Semaphore 0 .
Semaphore
1 .
‣ cnt: Semaphore
Embedded System Lab. II 73

Semaphore Management (Cont’d)
• OSSemCreate() ECB
Embedded System Lab. II 74

Semaphore Management (Cont’d)
• Semaphore / OSSemDel()
Semaphore Semaphore Task
.
• Semaphore / OSSemPend()
Semaphore .
‣ Pevent: Semaphore ECB .
‣ Timeout: (Clock Tick ).
‣ Err: .
Embedded System Lab. II 75

Semaphore Management (Cont’d)
• Semaphore / OSSemPost()
Semaphore .
‣ Pevent: Semaphore ECB .
• Semaphore / OSSemAccept()
Semaphore Task
Semaphore
‣ Pevent: Semaphore ECB
Embedded System Lab. II 76

Semaphore Management (Cont’d)
• Semaphore / OSSemQuery()
Semaphore ECB .
‣ Pevent: Semaphore ECB
‣ Pdata: Semaphore
Embedded System Lab. II 77

Mutual Exclusive Semaphore
Embedded System Lab. II

Mutual Exclusive Semaphore
• Mutual Exclusive Semaphore
Task .
Mutex MicroC/OS-II Semaphore
Binary Semaphore.
Mutex configuration constants in OS_CFG.H
uC/OS-II Mutex Service
OSMutexAccept()
Enabled when set to 1 in OS_CFG.H
OS_MUTEX_ACCEPT_EN
OSMutexCreate()
OSMutexDel()
OS_MUTEX_DEL_EN
OSMutexPend()
OSMutexPost()
OSMutexQuery()
OS_MUTEX_QUERY_EN
Embedded System Lab. II 79

Event Flags Management
Embedded System Lab. II

Event Flags Management
• Event Flags Management
Event Flags 2 .
‣
‣ Task
Event Flags Task
Event Flags configuration constants in OS_CFG.H
uC/OS-II Event Flags Service
OSFlagAccept()
Enabled when set to 1 in OS_CFG.H
OS_FLAG_ACCEPT_EN
OSFlagCreate()
OSFlagDel()
OS_FLAG_DEL_EN
OSFlagPend()
OSFlagPost()
OSFlagQuery()
OS_FLAG_QUERY_EN
Embedded System Lab. II 81

Event Flags Management (Cont’d)
• Event Flags Service
OSFlagCreat( )
OSFlagDel( )
OSFlagPost( )
OSFlagAccept( )
OSFlagPend( )
OSFlagQuery( )
ISR
OSFlagPost( ) OSFlagAccept( )
OSFlagQuery( )
ISR
Embedded System Lab. II 82

Event Flags Management (Cont’d)
• Event Flags
Event Flags Group Structure
typedef struct { /* Event Flag Group */
INT8U OSFlagType; /* Should be set to OS_EVENT_TYPE_FLAG */
void *OSFlagWaitList; /* Pointer to first NODE of task waiting on event flag*/
OS_FLAGS OSFlagFlags; /* 8, 16 or 32 bit flags */
} OS_FLAG_GRP;
Event Flags Group Node Structure
typedef struct { /* Event Flag Wait List Node */
void *OSFlagNodeNext; /* Pointer to next NODE in wait list */
void *OSFlagNodePrev; /* Pointer to previous NODE in wait list */
void *OSFlagNodeTCB; /* Pointer to TCB of waiting task */
void *OSFlagNodeFlagGrp; /* Pointer to Event Flag Group */
OS_FLAGS OSFlagNodeFlags; /* Event flag to wait on */
INT8U OSFlagNodeWaitType; /* Type of wait: */
} OS_FLAG_NODE;
Embedded System Lab. II 83

Event Flags Management (Cont’d)
• Event Flags Group, Event Flags Node, TCB
OS_FLAG_GRP
OS_FLAG_NODE
OS_EVENT_
TYPE_FLAG
NULL
AND OR
AND OR
NULL
Embedded System Lab. II 84

Event Flags Management (Cont’d)
• Event Flags Group / OSFlagsCreate()
Event Flags Group .
• Event Flags Group / OSFlagsDel()
Event Flags Group .
• Event / OSFlagPend()
Event Flags Group .
• Event Flags Group / OSFlagPost()
Event Flags Group .
• Event Flags Group / OSFlagQuery()
Event Flags Group .
Embedded System Lab. II 85

Message Mailbox
Embedded System Lab. II

Message Mailbox Management
• Message Mailbox
Message Mailbox MicroC/OS-II Kernel Object, Task
ISR Task .
Mailbox configuration constants in OS_CFG.H
MicroC/OS-II Mail Box Service
OSMboxAccept()
Enabled when set to 1 in OS_CFG.H
OS_MBOX_ACCEPT_EN
OSMboxCreate()
OSMboxDel()
OS_MBOX_DEL_EN
OSMboxPend()
OSMboxPost()
OSMboxPostOpt()
OSMboxQuery()
OS_MBOX_POST_EN
OS_MBOX_POST_OPT_EN
OS_MBOX_QUERY_EN
Embedded System Lab. II 87

Message Mailbox Management (Cont’d)
• Task, ISR, Mailbox
Embedded System Lab. II 88

Message Mailbox Management (Cont’d)
• Mailbox / OSMboxCreate()
Mailbox , Mailbox
NULL .
NULL
Mailbox .
‣ Msg: Mailbox
Embedded System Lab. II 89

Message Mailbox Management (Cont’d)
• OSMboxCreate() ECB
Embedded System Lab. II 90

Message Mailbox Management (Cont’d)
• Mailbox / OSMboxDel()
Mailbox Mailbox Task
.
• Mailbox / OSMboxPend()
Mailbox .
‣ Pevent: Mailbox ECB
‣ Timeout: (Clock Tick )
‣ err:
Embedded System Lab. II 91

Message Mailbox Management (Cont’d)
• Mailbox / OSMboxPost()
Mailbox .
‣ Pevent: Mailbox ECB
‣ Msg:
• Mailbox / OSMboxPostOpt()
Mailbox Task Broadcast
‣ Pevent: Mailbox ECB
‣ Timeout: (Clock Tick )
Embedded System Lab. II 92

Message Mailbox Management (Cont’d)
• / OSMboxAccept()
Task .
‣ Pevent: Mailbox ECB
• Mailbox / OSMboxQuery()
Mailbox ECB .
‣ Pevent: Mailbox ECB
‣ Pdata: Message Mailbox
Embedded System Lab. II 93

Message Queue Mailbox
Embedded System Lab. II

Message Queue Management
• Message Queue
Message Queue Task ISR Task
Kernel Object.,
‘’ .
Message queue configuration constants in OS_CFG.H.
uC/OS-II Event Flag Service
OSQAccept()
Enabled when set to 1 in OS_CFG.H
OS_Q_ACCEPT_EN
OSQCreate()
OSQDel()
OSQFlush()
OS_Q_DEL_EN
OS_Q_FLUSH_EN
OSQPend()
OSQPost()
OSQPostFront()
OSQPostOpt()
OSQQuery()
OS_Q_POST_EN
OS_Q_POST_FRONT_EN
OS_Q_POST_OPT_EN
OS_Q_QUERY_EN
Embedded System Lab. II 95

Message Queue Management (Cont’d)
• Task, ISR, Message Queue
Embedded System Lab. II 96

Message Queue Management (Cont’d)
• Message Queue Structure
Embedded System Lab. II 97

Message Queue Management (Cont’d)
• List of free queue control blocks
Embedded System Lab. II 98

Message Queue Management (Cont’d)
• A message queue as a circular buffer of pointers
Embedded System Lab. II 99

Message Queue Management (Cont’d)
• Message Queue / OSQCreate()
Message Queue , Message Queue
OSQCreate() .
‣ Start:
void .
void *MessageStorage[size]
‣ Size:
• Message Queue / OSQDel ()
Message Queue , Message Queue
Task .
Embedded System Lab. II 100

Message Queue Management (Cont’d)
• Message Queue / OSQPend()
Message Queue .
‣ Pevent: ECB
‣ Timeout: (Clock Tick )
‣ Err:
• FIFO / OSQPost()
FIFO Message Queue .
‣ Pevent: ECB
‣ Msg: . NULL .
Embedded System Lab. II 101

Message Queue Management (Cont’d)
• LIFO / OSQPostFront()
LIFO Message Queue .
‣ Pevent: ECB
‣ Msg: . NULL .
• FIFO LIFO / OSQPostOpt()
OSQPostOpt() OSQPost() OSQPostFront()
.
Task Broadcast .
Embedded System Lab. II 102

Message Queue Management (Cont’d)
• / OSQAccept()
.
OSQPend() Task
.
‣ Pevent: ECB
• Message Queue / OSQFlush()
Message Queue , .
• Message Queue / OSQQuery()
Message Queue .
• Pevent: ECB
• Pdata: Message Queue
Embedded System Lab. II 103

Message Queue Management (Cont’d)
• Message Queue
Embedded System Lab. II 104

Memory Management
Embedded System Lab. II

Memory Management
• Memory Management
malloc()
free() . .
MicroC/OS-II malloc() free()
.
Memory management configuration constants in OS_CFG.H
uC/OS-II Memory Service
Enabled when set to 1 in OS_CFG.H
OSMemCreate()
OSMemGet()
OSMemPut()
OSMemQuery()
OS_MEM_QUERY_EN
Embedded System Lab. II 106

Memory Queue Management (Cont’d)
• Memory Control Block
Memory Control Block Data Structure
Typedef struct {
void *OSMemAddr; //
void *OSMemFreeList; //
INT32U OSMemBlkSize; //
INT32U OSMemNBlks; //
INT32U OSMemNFree; //
} OS_MEM;
Embedded System Lab. II 107

Memory Queue Management (Cont’d)
• Memory Partition
Memory Partition
Memory Partition
Embedded System Lab. II 108

Memory Queue Management (Cont’d)
Free Memory Control Block List
Embedded System Lab. II 109

Memory Queue Management (Cont’d)
• / OSMemCreate()
32 100
OS_MEM *CommTxBuf;
INT8U CommTxPart[100][32];
void main (void)
{
INT8U err;
OSInit();
.
.
CommTxBuf = OSMemCreate(CommTxPart, 100, 32, &err);
.
.
OSStart();
}
Embedded System Lab. II 110

Memory Queue Management (Cont’d)
• OSMemCreate()
Embedded System Lab. II 111

Memory Queue Management (Cont’d)
• / OSMemGet()
.
‣ Pmem:
‣ Err:
• / OSMemPut()
.
‣ Pmem:
‣ Pblk:
Embedded System Lab. II 112

Memory Queue Management (Cont’d)
• / OSMemQuery()
.
‣ Pmem:
‣ Pdata:
Embedded System Lab. II 113

Memory Queue Management (Cont’d)
•
Embedded System Lab. II 114

MicroC/OS
/OS-II Porting
Embedded System Lab. II

MicroC/OS
/OS-II Porting
• Porting
Real Time kernel
.
, MicroC/OS-II .
• Porting MicroC/OS-II
MicroC/OS-II C .
C .
• MicroC/OS-II
C
C ,
Embedded System Lab. II 116

MicroC/OS
/OS-II Porting (Cont’d)
uC/OS-II File Structure
Embedded System Lab. II 117

MicroC/OS
/OS-II Porting (Cont’d)
OS_CPU.H
#define ,
OS_CPU_A.ASM
OS_CPU_C.C
C (Low-Level)
.
C
C
OS_CFG.H
MicroC/OS-II
INCLUDES.H
C ,
.
Embedded System Lab. II 118

MicroC/OS
/OS-II Porting (Cont’d)
• OS_CPU.H
, C
.
‣ Ex) 16 , Integer 16 32
, Integer 32 .
typedef unsigned char BOOLEAN;
typedef unsigned char INT8U; /* 8 */
typedef signed char INT8S; /* 8 */
typedef unsigned int INT16U; /* 16 */
typedef signed int INT16S; /* 16 */
typedef unsigned long INT32U; /* 32 */
typedef signed long INT32S; /* 32 */
typedef float FP32; /* */
typedef double FP64; /* */
typedef unsigned int OS_STK; /* 16 */
Embedded System Lab. II 119

MicroC/OS
/OS-II Porting (Cont’d)
• OS_CPU.H
OS_ENTER_CRITICAL() OS_EXIT_CRITICAL()
‣ MicroC/OS-II Critical Section
‣ OS_CPU.H OS_ENTER_CRITICAL() OS_EXIT_CRITICAL()
.
{
}
.
OS_ENTER_CRITICAL();
/* MicroC/OS-II Critical Section Code */
OS_EXIT_CRITICAL();
.
Embedded System Lab. II 120

MicroC/OS
/OS-II Porting (Cont’d)
• OS_ENTER_CRITICAL() OS_EXIT_CRITICAL()
OS_CRITICAL_METHOD == 1
‣ OS_ENTER_CRITICAL():
‣ OS_EXIT_CRITICA():
‣ : MicroC/OS-II
.
#define OS_ENTER_CRITICAL() disable_int() /* */
#define OS_EXIT_CRITICAL() enable_int() /* */
OS_CRITICAL_METHOD == 2
‣ OS_ENTER_CRITICAL():
‣ OS_EXIT_CRITICAL():
#define OS_ENTER_CRITICAL() \
asm(“ PUSH PSW”); \
asm(“ DI”);
#define OS_EXIT_CRITICAL() \
asm(“POP PSW”);
Embedded System Lab. II 121

MicroC/OS
/OS-II Porting (Cont’d)
• OS_ENTER_CRITICAL() OS_EXIT_CRITICAL()
OS_CRITICAL_METHOD == 3
‣ PSW C
.
#define OS_ENTER_CRITICAL() \
cpu_sr = get_processor_psw();
disalble_interrupts();
#define OS_EXIT_CRITICAL() \
set_processor_psw(cpu_sr);
Embedded System Lab. II 122

MicroC/OS
/OS-II Porting (Cont’d)
• OS_CPU_C.C
C
, 10 C
OSTaskStkInit() .
OSTaskStkInit()
OSTaskCreateHook()
OSTaskDelHook()
OSTaskSwHook()
OSTaskIdleHook()
OSTaskStatHook()
OSTimeTickHook()
OSInitHookBegin()
OSInitHookEnd()
OSTCBInitHook()
Embedded System Lab. II 123

MicroC/OS
/OS-II Porting (Cont’d)
• OSTaskStkInit()
OSTaskStkInit() OSTaskCreate() OSTaskCreateExt()
.
OS_STK *OSTaskStkInit ( void (*task) (void *pd), void *pdata, OS_STK *ptos, INT16U opt )
{
(1) (pdata)
(2) ISR ;
(3) .
(4) .
}
OSTaskStkInit()
Embedded System Lab. II 124

MicroC/OS
/OS-II Porting (Cont’d)
• OS_CPU_A.ASM
, 4 .
, 4
C .
OSStartHighRdy()
OSCtxSw()
OSIntCtxSw()
OSTickISR()
Embedded System Lab. II 125

MicroC/OS
/OS-II Porting (Cont’d)
• OSStartHighRdy()
OSStartHighRdy() OSStart()
Task .
.
void OSStartHighRdy()
{
(1) OSTaskSwHook() ;
(2) OSRunning = TRUE;
(3) Task :
Stack pointer = OSTCBHighRdy->OSTCBStkPtr;
(4) Task ;
(5) ;
}
Embedded System Lab. II 126

MicroC/OS
/OS-II Porting (Cont’d)
• OSCtxSw()
Task
TRAP . ISR, TRAP
OSCtxSw() .
OSCtxSw() TaskTask
MicroC/OS-II .
Void OSCtxSw(void)
{
(1) ;
(2) Task Task TCB
OSTCBCur->OSTCBStkPtr = ;
(3) OSTaskSwHook();
(4) OSTCBCur = OSTCBHighRdy;
(5) OSPrioCur = OSPrioHighRdy;
(6) Task :
= OSTCBHighRdy->OSTCBStkPtr;
(7) Task ;
(8) ;
}
Embedded System Lab. II 127

MicroC/OS
/OS-II Porting (Cont’d)
• OSTickISR()
MicroC/OS-II
.
Void OSTickISR(void)
{
(1) ;
(2) OSIntEnter() OSIntNesting 1 ;
(3) if( OSIntNesting == 1) {
OSTCBCur->OSTCBStkPtr = ;
}
(4) ;
(5) ( );
(6) OSTimeTick();
(7) OSIntExit();
(8) ;
(9) ;
}
Embedded System Lab. II 128

MicroC/OS
/OS-II Porting (Cont’d)
• OSIntCtxSw()
OSIntCtxSw() OSIntExit() ISR
Void OSIntCtxSw(void)
{
(1) OSTaskSwHook() ;
(2) OSTCBCur = OSTCBHighRdy();
(3) OSPrioCur = OSPrioHighRdy();
(4) Task :
= OSTCBHighRdy->OSTCBStkPtr;
(5) Task ;
(6)
}
Embedded System Lab. II 129