An embedded system refers to an electronic system that is designed to perform one or two specific functions within a larger system. This larger system is comprised of hardware such as mechanical components and electrical parts.
A real-time system, on the other hand, refers to hardware or software that operate with a time constraint. Stefan M. Petters defines real-time systems as information processing systems that respond to externally generated stimuli within a specific period. These systems provide guaranteed worst-case response time to critical events and acceptable average-case response time to non-critical events. Real-time systems that are designed as an embedded component are referred to as real-time embedded systems.
Basics of embedded and real-time systems
Embedded systems are managed by microcontrollers and digital signal processors that have single or multiple processing cores. Embedded system can either be programmable or non-programmable depending on the application. They are comprised of:
- System hardware: such as processors, timers, and output circuits
- System software: written to perform specific actions and provide code stored in a non-volatile memory within the hardware
- Operating system: completes and delivers work. It includes memory and processors.
Real-time systems can be classified into soft, firm, or hard real-time systems. Their correctness depends on the logical results produced as well as the time at which they are produced. Missed deadlines are catastrophic in these systems and can lead to huge losses of data in your workplace. This calls for the use of office VPN to prevent hackers who might slow down the system. These systems:
- Are time critical
- Control and monitor the environment
- Have sensors to collect data from the environment and actuators to change the systems environment
Examples of embedded and real-time systems
This section explores real-life examples of both systems.
- Washing machines: embedded systems in washing machines close and open valves to let water in and out of the machine at set intervals.
- Cars: modern cars are reliant on multiple embedded systems such as airbags, traction control systems, stability controls, and anti-lock braking system (ABS)
- Medical equipment uses these systems to monitor vital signs such as electronic stethoscopes that amplify sound and non-invasive medical imaging internal inspection equipment lie MRI and CT scans.
- Home security systems: such as smoke sensors, temperature sensors, and gas sensors.
Examples of real-time systems include:
- Air traffic control systems
- Command control systems
- Networked multimedia systems
- Temperature reading sensors