Basic Model of a Real-time System
Real-time System is a system that is used for performing some specific tasks. These tasks are related with time constraints and need to be completed in that time interval.
Basic Model of a Real-time System: The basic model of a real-time system presents the overview of all the components involved in a real-time system. Real-time system includes various hardware and software embedded in a such a way that the specific tasks can be performed in the time constraints allowed. The accuracy and correctness involved in real-time system makes the model complex. There are various models of real-time system which are more complex and are hard to understand. Here we will discuss a basic model of real-time system which has some commonly used terms and hardware. Following diagram represents a basic model of Real-time System:
Sensor: Sensor is used for the conversion of some physical events or characteristics into the electrical signals. These are hardware devices that takes the input from environment and gives to the system by converting it. For example, a thermometer takes the temperature as physical characteristic and then converts it into electrical signals for the system.
Actuator: Actuator is the reverse device of sensor. Where sensor converts the physical events into electrical signals, actuator does the reverse. It converts the electrical signals into the physical events or characteristics. It takes the input from the output interface of the system. The output from the actuator may be in any from of physical action. Some of the commonly used actuator are motors and heaters.
Signal Conditioning Unit: When the sensor converts the physical actions into electrical signals, then computer can’t used them directly. Hence, after the conversion of physical actions into electrical signals, there is need of conditioning. Similarly while giving the output when electrical signals are sent to the actuator, then also conditioning is required. Therefore, Signal conditioning is of two types:
- Input Conditioning Unit: It is used for conditioning the electrical signals coming from sensor.
- Output Conditioning Unit: It is used for conditioning the electrical signals coming from the system.
Interface Unit: Interface units are basically used for the conversion of digital to analog and vice-versa. Signals coming from the input conditioning unit are analog and the system does the operations on digital signals only, then the interface unit is used to change the analog signals to digital signals. Similarly, while transmitting the signals to output conditioning unit the interface of signals are changed i.e. from digital to analog. On this basis, Interface unit is also of two types:
- Input Interface: It is used for conversion of analog signals to digital.
- Output Interface: It is used for conversion of digital signals to analog.