PROCESSORS

The processor of a computer is considered to be the heart of the system. Processors house sections for storage, arithmetic and logic, and control. The storage or memory function of a processor is responsible for input data storage, working storage space, output storage, and program storage. Data fed into the input storage area are held in memory until ready to be processed. The working storage space is like a sheet of scratch paper. It is used to hold data being processed and any intermediate result of processing. The output storage area is designed to hold the finished results of the processing operation until they can be released. The program storage area is responsible for holding all of the internal instructions of the processor. These functions of the processor are not fixed by built-in boundaries, but can vary from one application to another. A specific storage area may be called on to store input data in one application, output results in another, and processing instructions in a third. The program of the unit determines how storage space is utilized for a specific application. The arithmetic-logic unit (ALU) and control section of a processor are combined to form the CPU. Essentially, all calculations are performed and all comparisons or decisions are made in the ALU of the CPU. Once data are fed into input storage, they are held and transferred as needed to the ALU where processing takes place. No processing occurs in the input storage area. Any intermediate results generated in the ALU are temporarily placed in the working storage area. These data may

move from primary storage to the ALU and back again to the working storage area many times before processing is finished. Once the operation is complete, the final results are supplies to the output storage section and ultimately transferred to the output device. The type and number of ALU operations performed by the computer are determined by design of the CPU.

The control section of a computer is responsible for selecting, interpreting, program instructions, maintaining order, and directing system operations. The control section doesn’t process data, it acts like a central nervous system for other data-manipulating components of the computer. When processing begins, the first program instruction is selected and fed into the control section from

program storage area. It it then interpreted and sent to other components to execute the necessary action. Further program instructions are selected and executed on a continuous basis until the processing is completed.

8. Look through the 1 part of the text again and answer the following questions:

1. What does “computer” term mean?

2. What functions can computer perform?

3. What is a program?

4. What is the function of a program?

5. What is bit and byte?

6. What is the function of input device?

7. What types of input devices you know?

9. Read 2 part of the text and answer the questions:

1. What is a processor?

2. What is the function of processor?

3. What is the storage of a processor responsible for?

4. What is the function of ALU?

5. What determines the type and number of ALU operations performed by computer?

6. What is the function of the control section?

10. Read the 2 part of the text again and speak on processing using the words and word combinations given below:

Processor: the storage section, arithmetic and logic section, control section.

Storage section: input data storage, working storage space, output storage, program storage, to hold intermediate results, finished results, internal instructions of the processor, specific storage area, unit program.

ALU: CPU, calculations and comparisons, to transfer, processing takes place, operation is completed, final results, output storage section.

Control section: selecting, interpreting, executing program instructions, maintain order, to direct system operations, central nervous system, to select, to send, to execute.

TEXT B

MEMORY

1. Read the text and answer the questions:

1.In what way can the limited storage capacity be extended?

2. Describe the way of a secondary memory unit operation.

3. What types of computer memory do you know?

4. What happens to the hard-disk memory in case the disk is removed from the system?

To supplement the limited capacity of the primary storage section, most computers have a secondary or auxiliary memory unit. Memory devices of this type are connected directly to the processor. This is considered to be an on-line operation. The memory unit accepts and retains data and/or program instructions from the processor. It then writes data back to the processor as needed to complete the processing task. On-board or chip memory is usually built into the assembly board of a personal computer. In addition, a computer can have soft-disk memory and hard-disk memory that extends the memory of the system to an unlimited capacity. This memory remains intact after the disc is removed from the system. Since the processor no longer has direct and unassisted access to this memory, its storage capability is considered to be off line.

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