- Small change in electronic components, increase in power of microprocessor and increase in capacity of main memory and hard disk continued during fifth generation.
- VLSI became ULSI (Ultra Large Scale Integration) in fifth generation and chips having ten million electronic component.
- Storage technology also increased during this fifth generation, optical disk also emerged as a popular portable mass storage media such as CD-ROM.
- In fifth generation outgrowth of computer network, this trend is result in popularity of internet. Internet provide computer user to sitting across the globe to communicate with each other within a minutes using Electronic Mail.
- Some application emerged during this time e.g. Electronic commerce, Virtual libraries, virtual classrooms, distance education.
- Popular tool for wide range for multimedia (text, graphics, animation, audio, video) application because high processing power and storage capacity.
- The data size of multimedia application is much larger than textual information because representation of graphics, animation, audio, video.
- Average number of electronic components packed on a silicon chip doubled each year after 1965.
- This progress soon led to era of the Large Scale Integration (LSI) with possible to integrate 30,000 electronic component on single chip & Very Large Scale Integration (VLSI) with possible to integrate about One Million electronic component on a single chip. This led to creation of Microprocessor.
- Microprocessor contains all circuits needed to perform arithmetic logic and control functions, the core activities of all computer on a single chip.
- It started new social revolution called Personal Computer (PC) revolution.
- Semiconductor memories replaced magnetic memory core memories. Hard disk become cheaper, smaller and larger in capacity. Floppy disk become very popular as a portable media for porting program and data from computer to another computer.
- High speed computer network enable to enter connection of multiple computers to enable them communicate and share data.
- Local Area Network (LAN)became popular for connecting computers within small organization or within campus.
- Wide Area Network became popular for connecting computers located at large distance.
- Several new OS were developed during this period like MS-DOS, MSWindows and etc.
- Graphical User Interface (GUI) is developed for making computer more user friendly. It provides icons and menus that user can select with mouse.
- Powerful word processing packages that allows easy development of document, spreadsheet packages that allowed easy manipulation and analysis of data in form of rows and columns, graphics packages that allowed easy drawing of pictures and diagrams.
- Multiple windows on single terminal screen.
- UNIX operating system and C Programming languages become very popular.
Central Processing Unit (CPU):
- CU and ALU of computer system are together known as the Central Processing Unit (CPU). It is a brain of computer system.
- In computer system all major calculation comparisons takes place inside CPU and it is responsible for activating and controlling the operations of other units of computer system.
- CPU performs all types of data processing operation. It store data , intermediate result and instrunctions(Program).
Arithmetic Logic Unit (ALU)
- It is the place where actual execution of instruction takes place during processing.
- Calculations are performed and all decisions are made in the ALU.
- First of all data are stored in primary storage and, transfer it to ALU when it is needed after that again it is transferred to primary storage. This process happened many times within the completion of process.
- ALU can perform four basic arithmetic operation (Add, Subtract, Division, Multiplication) and logical operations or comparisons such as less than, equal to.
- Some projects are built without conducting analysis and design. The Product is simply built and tested again until the customer needs are satisfied. This approach is termed build and fix model as shown below:
- The build and fix model may work well on small programs approximately 50 200 lines.
- If the defect is detected in the later phase then cost of correcting it increases exponentially.
- Hence cost of fixing defects of the program developed using build and fix model is higher as compared to the cost of defect correction in any program which is developed using any other specified software development life cycle model.
- Simple and easy to understand
- Only applicable to very small sized programs
- Produced unenhancable source code
- Requirements are not predetermined
- Frequent changes produce unstructured or poorly structure source code
- Cost of fixing defects is high
- Maintenance of software becomes very difficult without any requirement or design documents
Computer speakers or multimedia speakers , are speakers external to a computer , that disable the lower fidelity built-in speaker. They often have a low-power internal amplifier. The standard audio connection is a 3.5 mm (approximately 1/8 inch) stereo phone connector often color-coded lime green (following the pc 99 standard) for computer sound cards. A few use an RCA connector for input. There are also USB speakers which are powered from the 5 volts at 500 miliamps provided by the USB port , allowing about 2.5 watts of computer power.
Computer speakers range widely in quality and in price. The computer speakers typically packaged with computer systems are small plastic , and have mediocre sound quality. Some computer speakers have equalization features such as bass and treble controls.
The internal amplifiers require an external power source , usually an AC adapter. More sophisticated computer speakers can have a subwoofer unit , to enhance bass speaker , and the small satellite speakers.