Chapter II - Real-Time Systems Concepts

1. What is the Real Time? ¶

1.1. Real Time System ��� ������ 범��� ¶

1.2. Foreground / Background System ¶

1.3. Critical Section of Code ¶

1.4. Resource ¶

1.5. Shared Resource ¶

1.6. Multitasking ¶

1.7. Task ¶

1.8. Context Switch ( or Task Switch) ¶

1.9. Kernel ¶

1.10. Scheduler ¶

1.11. Non - Preemptive Kernel (�� ��������� ������) ¶

1.12. Preemptive Kernel (��������� ������) ¶

1.13. Reentrancy ¶

~cpp 
void strcpy (char * dest , char * src){
 while (*dest++ = *src++) {
   ;
 }
 *dest = NUL;
}

~cpp 
int Temp;  // ������ 바뀔��� 모르는 ������ 변���
void swap(int *x,int *y)
{
 Temp = *x;
 *x = *y;
 *y = Temp;
}

1.14. Round Robin Scheduling ¶

1.15. Task Priority ¶

1.16. Static Priority ¶

1.17. Dynamic Prioirty ¶

1.18. Priority Inversions ¶

1.19. Assigning Task Priorities ¶

~cpp 
   ������  다���과 같다.
   --  E(i)        1/n
   >   ---- < n ( 2    - 1 )
   --  T(i)
   i

   ������ ������ 보겠나...

1.20. Mutual Exclusion ¶

1.21. DeadLock ¶

1.22. Synchronization ¶

1.23. Event Flags ¶

1.24. Intertask Communication ¶

1.25. Message MailBoxes ¶

1.26. Message Queues ¶

1.27. Interrupts ¶

1.28. Interrupt Latency ¶

1.29. Interrupt Response ¶

1.30. Interrupt Recovery ¶

1.31. ISR Processing Time ¶

1.32. Nonmaskable Interrupts (NMIs) ¶

1.33. Clock Tick ¶

1.34. Memory Requirements ¶

1.35. Advantages and Disadvantages of Real-Time Kernels ¶