IndianTechnoEra: The Computer Generations [Short Intro]

The Computer Generations

Generation

In computer talk is a step in technology. It provides a framework for the growth of the copter industry. Original, the term generation was used to distinguish between varying hardware technologies. But nowadays it has been extended to include both the hardware and the software, which together make up an entire computer system.

First Generation (1942-1955)

We have already discussed about some of the early computers ENIAS, EDVAC, EDSAC, etc. these machines and other of their time were made possible by the inventions of “vacuum tube”, which was a fragile glass device that could control and amplify electronic signals these vacuum tube computers are referred to as first generation computers.

Characteristics:

• The first generation computers’ control was centralized in single CPU.
• Ferrite – core main memory was started as strong.
• Use of virtual memory and register started.
• Punch card used as input device.
• Magnetic tapes and magnetic drums used as secondary memory.
• Binary code or machine language was used for programming.
• Advent of von-Neumann architecture

            Ex- IBM-650

Advantages:

• Vacuum tubes were the only electronic component available during those days.
• Vacuum tube technology made possible the advent of electronic digital computer.
• These computes were the fastest calculation devices of their time.
• They could perform computations in milliseconds.

Disadvantages:

• Too bulky in size
• Unreliable
• Thousands of vacuum tubes that were used emitted large about of heat and burnt out frequent
• Air conditioning required.
• Prone to frequent hardware failures
• Constant maintained required.
• Non-portable
• Manual assembly of individual components into functioning unit required.
• Commercial production was difficult and costly.
• Limited commercial use

Second Generation (1955-1964)

The transistor is a smaller and more reliable successor to the vacuum tube, was invented in 1947. However, computers that used transistors were not produced in quantity until over a decade later. The second generation emerged with transistor being the brain of the computer.

With both the first and the second generation’s computers, the basic component was a discrete or separate entity. The many thousands of individual components had to be assembled by hand into functioning circuits. The manual assembly of individual components and the cost of labors involved at this assembly stage made the commercial reduction of theses computers difficult and costly.

The second generation of computers started with the advent of transistors.

What Is Transistor?

It is made from silicon. It is cheaper and smaller than vacuum tube. Unlike vacuum tubes a transistor does not require wired, metal glass capsule and vacuum therefore, it is called solid-state device the transistor was invented in 1947 and has launched the electronic resolution in 1950

Characteristics:

• Greater speed, large memory capacity and smaller size than the previous generation
• More advanced in terms of ALU & CU
• Assembly language was used for programming.
• Cost reduced.
• Less power consuming.
• High-level languages were beginning to be used and provisions for system software were starting.

Advantage:

• Smaller in size as compared to first generation computers
• More reliable
• Less heat generated.
• These computers are able to reduce computational times from seconds to microseconds
• Less prone to hardware failures
• Better portability
• Wider commercial use

Disadvantage:

• Air-conditioning required.
• Frequent maintenance required.
• Manual assembly of individual computed into a functioning unit was required.
• Commercial production was difficult and costly.

Third Generation (1967-1975)

Use of ICs in computer defines the third generation of computer. Computers of third generations are faster than previous generations. Due to ICs the size of the computer reduced in this generations.

Ex-IBM system/360 family have model 30, 40, 50, 65.

Integrated Circuits (ICs)

ICs are collection of transistor, registers and conductors. They are fabricated on a semiconductor material such as - Silicon. Hundreds or even thousands of transistors could be fabricated on a single wafer of Silicon. These fabricated transistors can be connected with a process of metallization to form logic circuits on the same chip. The silicon wafer is divided into a metric of small area. Size of area is few millimeters. Circuit pattern is fabricated on each of these areas and then wafer is broken into chip.

Chip

Each chip consists of several gated, which are made using transistors only and a number in input and output connection points. Each chip can be packaged separately in a housing to protect it.

Hundreds or even thousands of transistors could be fabricated on a single wafer of silicon. Wafer divided into 5 mm square area, where chip fabricated.

Characteristic:

• ICs was used on the place of transistor.
• High-level language was used for programming memory size increase.
• Certain new techniques were introduced to increase the effective speed of program execution.
• Semi conductor memories were starting on the place of ferrite core memory as main memory.

Advantage:

• Smaller in size as compared to previous generation computers
• Even more reliable than second-generation computer
• Even lower heat generated than second generation computers.
• These computers were able to reduce computations times from microseconds to nanoseconds.
• Maintenance cost is low because hardware failure is rare.
• Portable
• Totally general purpose. Widely used for various commercial applications all over the world.
• Less pore requirement that previous generation computer.
• Manual assembly of infidel components into a functioning unit not required. So human labor and cost involved at assembly strafe reduced spastically.
• Commercial production was easier and cheaper.

Disadvantages:

• Air-condition required in many cases.
• Highly sophisticated technology required for the manufacture of IC chips.

Fourth Generation (1975-Onwards)

Initially, the integrate circuits contained only about ten to twenty component.

Characteristics:

• On the basis of number of gate integrated on a single chip ICs can be classified into following categories.
• Small – Scale Integration (SSI): Only few gates (components) were integrated on a chip and then packages.
• Medium – Scale Integration (MSI): Hundreds (100) of gated were fabricated on a single chip.
• Large – Scale Integration (LSI): There are 1000 of gated were fabricated on a single chip.
• Very – Large Scale Integration (VLSI): There are 1000,000 gates are fabricated on a single chip.
• Ultra - Scale Integration (ULS): There are 1000,000,000 components are expected to be fabricated.

                Ex-Intel 8080

Advantage:

• Smallest in size because of high components density
• Very reliable
• Hear generation if negligible.
• No air conditioning required in most cases.
• Much faster in computation those previous generations
• Hardware failure is negligible and hence minimal maintenance is required.
• Portable because of their small size
• Totally general purpose
• Cheapest among all generations

Disadvantage:

• Highly sophisticated technology required for the manufacture of LSI chips.

Fifth Generation (Yet To Come)

Scientists are now at work on the fifth generation computers 0 a promise, but not yet a reality. They aim to bring us machines with genuine I.Q., the ability to reason logically, and with real knowledge of the world. Thus, unlike the last four generations, which naturally followed its predecessor, the generation will be totally different, totally novel, and totally new.

 

Questions from this unit:

1. What is generation?
2. What is computer generation?
3. What is first generation computer?
4. What is characteristic of first generation computer?
5. What is advantage of first generation computer?
6. What is disadvantage of first generation computer?
7. What is second generation computer?
8. What is characteristic of second generation computer?
9. What is advantage of second generation computer?
10. What is disadvantage of second generation computer?
11. What is third generation computer?
12. What is characteristic of third generation computer?
13. What is advantage of third generation computer?
14. What is disadvantage of third generation computer?
15. What is fourth generation computer?
16. What is characteristic of fourth generation computer?
17. What is advantage of fourth generation computer?
18. What is disadvantage of fourth generation computer?
19. What is fifth generation computer?
20. What is characteristic of fifth generation computer?
21. What is advantage of fifth generation computer?
22. What is disadvantage of fifth generation computer?
23. What is transistor?
24. What is the characteristic of transistors?
25. What is the advantage of transistors?
26. What is the disadvantage of transistors?
27. What are integrated circuits?
28. What is ICs?
29. What is chip?