microprocessor applications

1.1  Microprocessor Applications and Real-Time Systems

• Microprocessors are used to handle a set of tasks that control one or more external events or systems.

• Microprocessors are typically used in either reactive or embedded systems.

• Reactive systems are those that have an ongoing interaction with their environment - for example, a fire-control system that constantly reacts to buttons pressed by a pilot.

• Embedded systems are those used to control specialized hardware in which the computer system is installed - for example, the microprocessor system used to control the fuel/air mixture in the carburetor of many automobiles.
•  In embedded systems the software system is completely encapsulated by the hardware that it controls.

• Often the processor is required to manage various different tasks that have to be scheduled somehow and must also deal with outside interrupt sources such as an alarm when something goes wrong.

• Real-time systems are those in which timeliness is as important as the correctness of the outputs, although this does NOT mean that they have to be �fast systems�.

• A real-time system does not have to process data in microseconds to be considered real-time - it must simply have response times that are constrained and thus predictable.

---

Table of Contents