Embedded systems are one of the most growing field in electrical engineering. Thousands of embedded system engineers are working on different embedded systems projects each day and they are producing more and more innovative technologies for this world. Embedded systems are used in many application starting from domestic application to industrial applications. Medical equipments, Mobile phones, racing cars, smart phones, smart home system, Digital camera’s, automated control of industrial machines, smart tv and almost everything in home, offices, industry, airplanes have embedded system applications. All these devices have computer embedded in them. These computer are using programming languages. Mostly Linux operating system are running on these computers. Let us start learning about embedded system and its applications with basic introduction of embedded system.
What is embedded system?
Embedded system as it name suggests means embedding something into system. In embedded system a computer is embedded in s system to perform specific task. Embedded systems are built for special purpose for specific applications. For example in digital camera, a microcomputer is embedded in it. The purpose of micro computer in digital camera is take picture and some other functions to control which are already embedded in microcomputer in the form of programming instructions. Some embedded computers have Linux operating system running on it which perform specific tasks. Embedded system have different purpose for different people. For example someone want to control speed of dc motor through microcontroller, it is also a simplest embedded system and other person want to make smart phone which have embedded processors inside. So It have different applications for different people. Main overview of embedded system architecture is given below:
Embedded systems computers:
Embedded system is generally a computer but its functions are less than general purpose computers. because they have to perform only specific tasks. Embedded system computer contains CPU which runs on slow speed than general purpose computers to save power. It have less memory and processors also run on low-speed than general purpose computers. Other than this embedded system have a software running inside it. Embedded software development is also a main part of embedded system development. Some embedded systems used only C and C++ programming languages and some used embedded Linux system, its means they have Linux operating system running on them.
So embedded system used both hardware and software to control and monitor the working on many devices. Both hardware and software are the main part of embedded system projects.
Embedded system Hardware components :
As I have already mentioned above embedded systems are consists of both hardware and software. Embedded system have following hardware components:
- Central processing unit or microcontrollers.
- Power supply circuit
- Interfacing circuit like sensors, liquid crystal displays.
- ROM and RAM memory
- Input circuits
- output circuits
- Serial communication devices
Central processing unit or processor/ microcontroller:
Central processing unit is main components of embedded system. It is like a brain of system. It is programmed with the help of programming languages to perform specific tasks. Central processing unit is a integrated chip on computer. It contain arithmetic logic unit, real-time clock, stack pointer, program counter, serial ports, internal interrupts and external interrupt It can not do anything alone. Other peripherals are also connected with processor. Micro processor also have following components attached with it.
- Serial communications ports
- Input/output ports
On the other hand microcontroller is complete single chip integrated computer. It have built-in RAM, ROM, Timers, input/output ports. serial communications ports, analog to digital converters , counters and digital to analog converts which make them ready to use single chip integrated computer. microcontroller can be easily interfaced with sensors and other interfacing circuit due to build in input/output ports.Followings are famous families of micro controllers.
- Microchip PIC microcontrollers
- ARM microcontrollers
- AVR microcontrollers
- MSP microcontrollers
- Motorola microcontrollers
- intel 8051 microcontrollers
Microcontrollers have low-cost, small memory, slow speed and low power consumption as compared to digital signal processors. Microcontrollers can be easily interfaced with analog and digital sensors to control and monitor data, for data aquisition.
Embedded system software components:
Embedded software developers are also main part of embedded system development. If hardware is body of embedded system, then software is soul of embedded system. Many programming languages are used for embedded system development. In microcontrollers based projects, C programming language is used mostly. Many languages have been developed for embedded system and each programming language may be more useful for a specific applications. In other words one language may be useful for control and monitoring based projects and it may not be useful for singal processing and conditioning based embedded system projects. Following programming languages are used for embedded systems development.
- Hardware languages ( HDL and VHDL)
- Software languages ( C, C++, JAVA, Andriod, Linux)
- Data flow languages
- Hybrid languages
Embedded system circuits interfacing with physical world:
Embedded systems interface with external world through sensors and transducers. Sensors may be of analog or digital type. As you know microcomputers can only understand digital values. analog to digital converters are used to interface analog sensors with embedded system processors and microcontrollers. Many microcontrollers have built in analog to digital converter and digital to analog converters. For example in remote monitoring embedded system, you need to interface temperature sensor, light sensor, moisture sensor and others sensors to read its values. All these sensors are analog sensors. So you must need an analog to digital converter. Embedded systems also communicate with external devices using following features:
- Serial communication
- I2C communication
- CAN ( controller Area Network)
- Web servers
- Digital and analog input/output ports
Types of embedded system:
Embedded systems are classified into two group based on performance, functional requirement. According to use of processors and microcontrollers. Embedded systems have two types.
- Based on the performance of microcontrollers.
- Based on the performance and functional requirement.
Based on performance of microcontrollers, embedded systems are further classified into three group:
- Small scale embedded systems.
- Medium scale embedded systems
- Large scale embedded systems
Based on performance and requirement of embedded project, embedded systems are classified into four group:
- Real time embedded systems
- stand alone
- mobile applications embedded software
Applications of embedded system:
As I have already mentioned many examples of embedded systems in start of article. Embedded field have enormous applications in medical field, automation industry, Smart phone, smart Tv, Airplanes and many others. List of latest embedded system final year projects is given below:
- Home control system through voice
- Real time monitoring of electricity to save from theft
- Smart energy billing system
- smart grid monitoring system
- smart grid station
- Real time accident protection using gsm
- Remote monitoring system using gsm and pic microcontroller
- Smart grid management and visualization