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Verbs to remember



to modify

to place

to be termed

to provide

to run

 

Task 1Form the verbs:

Example: processing – to process

development – to develop

difference – to differ

Improvement – execution – provision – programming – operation – generation – discussion – translation – resistance –  

Task 2 Read the text and answer the following questions.

1 How do you understand the term «interleaving»?

2 What kind of instructions do second-generation computers have?

3 What were two important features of second-generation machines?

4 What is parallel processing technique?

5 What kind of characteristics became feasible with second generation computers?

Task 3 Explain the following in English:

1 Interleaving

2 I/O programs

3 Batch processing

4 Parallel processing

Task 4 Prepare a short talk on the following.

a) One of the important improvements of second generation computers was batch processing. What kind of mode operation was termed batch processing?

b) Why was parallel processing technique so important?

c) What kind of characteristics of second generation computers you think to be the most important?

Task 5 Write down 5-7 questions about the text.

Task 6 Sum up the text “The second generation: 1957-1964”.

TEXT 1 SECOND GENERATION COMPUTERS HISTORY OF DEVELOPMENT (PART 1)

 

Scientists at Bell Telephone Laboratories, led by John Bardeen, Walter Brattain, and William Shockley, developed in 1948 the first junction transistor. The potential advantage of the transistor over the vacuum tube was almost as great as that of the vacuum tube over the relay. The invention of the transistor made computers more widespread because of its dependability, small size, and lower power requirements. Therefore, the second generation was characterized mainly by the change from vacuum tube to transistor technology. Several other important developments also occurred.

Second-generation computers were faster, had increased storage capacity, and required less power to operate. Cathode ray tube and delay line memories of first-generation computers were replaced by ferrite cores as the primary internal storage medium. Cores are very small doughnut-shaped rings of magnetic material on which thin wires are wound. An electrical current passing through the wires magnetizes the core to represent either an ON or OFF state. In this way, groups of cores store instructions and data that can be located and retrieved for processing in a few mil­liseconds—much faster than with magnetic drum storage.

In many second-generation systems, the main memory of the computer was supplemented by using magnetic tapes for external, or auxiliary, storage. Substituting magnetic tapes for punched cards or punched paper tapes increased I/O processing speeds by a factor of at least 50. Other significant changes that occurred during this period were the development of magnetic disk storage, modular hardware, and improved I/O devices. The main advantage of disk storage is that it enables the user to locate a particular record on a set of disks, rotating at high speeds, in a fraction of a second. Unlike a magnetic tape, records on a disk do not have to be processed sequentially. The computer can go directly to the record it needs without having to read everything that comes before it. Thus disks provide direct, or random, access to records in a file.

The modular hardware concept involved using a building-block approach to the design of electronic circuits. With this approach, complete modules (breadboards) could be replaced, thus simplifying maintenance tasks. The improvement in I/O devices could be seen in faster printing speeds and automatic detection and correction of I/O errors. These advances allowed the devices to be connected directly (online) to the computer without significantly lowering the overall efficiency of the system. Special I/O processors were introduced to supervise I/O operations, thus freeing the CPU from many time-consuming bookkeeping functions. The use of an index register and floating-point arithmetic hardware became widespread.




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