JNTU IV B.Tech I Semester Supplimentary Examinations, February 2008
REAL TIME SYSTEMS
1. Explain the following in detail :
(a) Clock-based tasks
(b) Event-based tasks
(c) Interactive Systems.
2. Explain simple digital signal computer interface with the help of a figure for a Real
Time process control system.
3. (a) Define an exception. Explain exception handling in detail with an example.
(b) How exception handling is different in Real Time Systems? Explain
4. (a) Show that the periodic tasks (10,2), (15,5), and (25,9) are schedulable by the rate monotonic algorithm.
(b) Show that the periodic tasks (10,2) (12,5) and (15,4) are not schedulable by
the rate monotonic algorithm.
(c) Construct the initial segments in the time interval (0,75) of a rate monotonic schedule and a earliest-deadline-first schedule of the periodic tasks (10,2) (15,5) and (25,12).
5. (a) What are the typical design parameters of RTOS? Explain?
(b) What do you understand by “Interleaving”? How does CPU use it for multitasking?
6. (a) Write a short note on the following
i. Paisley System
ii. Dataflow diagrams.
(b) What are the different areas of applications of petri nets?
7. (a) “One way of implementing backward error recovery is to store the process state at pre specified moments in time”. Explain it.
(b) Explain the following
i. Parity coding
ii. Cyclic redundancy codes.
8. (a) What is meant by fault injection? Explain how it is used to measure an error Propagation time.
(b) Explain real life components, which have a hazard rate shaped according to the Bathtub curve.