Page 115 - DCAP608_REAL TIME SYSTEMS

Real Time Systems

Notes  no need for any synchronization mechanisms
 schedule can be represented as tables that is used by the scheduler at run time
 Relatively easy to validate
 Because times when jobs execute are deterministic, the system will not exhibit
anomalies
 Can prove scheduling feasibility by exhaustive simulation and testing
Disadvantages of clock-driven scheduling are discussed below:

 Inflexible, since schedule is computed off-line, small changes mean that new tables have
to be generated.
 Release times of jobs must be fixed

 Priority-driven does not require this
 A lot information about jobs has to be known beforehand, so that the schedule can be
precomputed.

 Difficult to get acceptable response times for aperiodic (soft real-time) jobs.

Task Prepare a presentation on Algorithm for Constructing Static Schedules.

Self Assessment

State whether the following statements are True or False:

10. Synchronization mechanism is very important for Clock –Driven Scheduling.
11. The sporadic jobs should be affected by the mode change.
12. DSP algorithms are non-terminating and repetitive.



Case Study Innovative Concepts and LynxOX Team Up to

Support U.S. Army Communications

I’s mobile, network, and communications systems are developed for global
enterprises seeking sophisticated solutions for complex voice, imagery, video,
Cand data. The company’s newly launched product line focuses on tactical and
wireless embedded communications systems, reinforcing its dynamic vision to ‘engineer
tomorrow’s communications.
Making Tactical Connections

ICI’s military communications equipment is designed for the United States Army and is
used primarily by Army aviation helicopters, such as Apache/Longbow, Kiowa Warrior,
cargo helicopters, and others. While the Army and Air Force employ many different
protocols to communicate, ICI’s IDM (improved data modem), a communications and

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