What is an embedded system?

A system is a collection of interconnected components that work together to achieve a common goal. However, embedded systems are designed for specific tasks and are less versatile than general-purpose computer systems. They are optimized to perform a particular or a set of functions and are often built with specialized hardware and software.

Structure

Embedded systems comprise three basic elements: hardware, software, and a real-time operating system (RTOS).

The hardware in an embedded system includes the following elements:

• Sensors: They are used to detect changes in environmental conditions.

• Analog-to-digital converters (ADC): They are used to convert analog signals collected by sensors into electrical signals so the embedded systems can read them. Digital-to-analog converters (DAC) are used to convert electrical signals into analog signals sent to the actuators.

• Processors: They process the incoming signals and other stored data to generate instructions to execute the required actions (if any).

• Actuators: They are used to implement the instructions given to them by the processor and perform actions in the environments to deal with any changes appropriately.

Note: Additionally, to make the embedded systems more user friendly a display and I/O devices may also be included.

Characteristics

• Specialized: Embedded systems are designed with a singular purpose, performing a specific task or set of tasks repeatedly. For example, a thermostat embedded in a heating system consistently regulates the temperature within a defined range.

• Memory: Embedded systems incorporate memory to store program code and data.

• Real-time operation: These systems are efficient enough to process inputs and other stored data in real time.

• Tightly constrained: These systems operate within strict constraints, including size, cost, power consumption, and performance. Size constraints ensure that the embedded system fits seamlessly into its intended application, cost constraints ensure affordability and power constraints are essential, especially for battery-powered devices.

• Microprocessors/microcontroller-based: While microprocessors execute instructions and manage tasks, microcontrollers (a specialized form of microprocessor) integrate the processing capabilities with dedicated memory and peripherals.

• Connected: A mechanism for connecting and configuring I/O devices should be available.

Note: Some embedded systems may not require external connectivity, depending on their intended function.

• Combination of hardware and software: It is a combination between dedicated hardware components and specialized compatible software to efficiently perform their designated tasks.

Pros and cons

Let’s look at the pros and cons of embedded systems.

Types of embedded systems

Embedded systems come in various types, each tailored to specific functional requirements and applications. Here are some examples:

• Mobile embedded systems: They are compact systems designed for on-the-go use. A good example is the embedded system within digital cameras, which efficiently captures and processes images while being portable.

• Networked embedded systems: They are interconnected within a network, enabling them to communicate with other systems. For example, a home security system that transmits data to monitoring centers and point-of-sale systems to facilitate sales tracking and inventory management in real time.

• Standalone embedded systems: They operate independently and do not rely on a host system. They excel in specialized tasks while maintaining autonomy. Devices like calculators and MP3 players are good examples because they serve singular purposes without external dependencies.

• Real-time embedded systems: They are designed to deliver output within precise time intervals. These systems find extensive application in critical sectors such as medicine, industry, and defense, where timely and accurate responses are essential. An example is a traffic control system that ensures safe and efficient traffic flow by responding to changing conditions in real time.

Understanding the types of embedded systems allows us to make an informed choice according to the system’s needs to ensure optimal performance and functionality.

Quiz