1. Embedded Operating System Leo Philip 10/5/2015.

2. Do we need an OS ?

3. Do we need an OS? ( continued ) Low complex system

4. Smart Card

5. Why do we need an OS?

6. Preemptive kernel

7. Threads A task is known as a thread. The design requires the application to divide the work into tasks. Each task is responsible for a portion of the problem at hand. Applications are easier to handle when multithreading is used.

8. Infinite loop Infinite loop is more common due to repetitive work needed in embedded systems. Scanning a keyboard.

9. Aircraft Embedded Systems Avionics Standards are concerned with 1. Level of criticality of software 2. Protection 3. Partition.

10. General purpose vs. Real time Efficient systems can also be built using general purpose operating systems.

11. States of a Task Dormant Ready Running Pending Interrupted

12. Interrupt management Interrupt controller

13. Resource Management and Synchronization Disable/ enable interrupts Semaphores Mutex

14. Memory management Dangerous to use malloc() and free() as it leads to fragmentation. Solution is to use fixed-size-block partition.

15. What did we learn?