1. Complete the following sentences using the words and expressions given below

1. The CPU processes collection of bits called ....

2. If the same program can run on two different computer ... they are said to be compatible.

3. A byte is the number of switches or bits that the CPU can receive from RAM/ROM at one ....

4. Comparison operations allow a program to make decisions based on its ... data.

5. Companies are now developing three-dimensional structures on the chips at nanotechnology ....

6. It is possible for many CPU's to share computing ... in one computer.

7. The ALU takes data from the ... storage area inside the CPU named registers.

responsibilities temporary bytes input scale brands time

2. Fill in the prepositions if necessary

The CPU is centrally located on the motherboard. The processor is responsible ... everything your computer does. For example, the CPU runs... the operating system, the software programs installed on your computer, and device peripherals such as printers and flatbed scanners. Since the CPU carries ... a large share of the work in the computer, data pass continually ... it. After processing, the data is sent back to the RAM and the units. The CPU continually receives instructions to be executed. Each type of CPU is designed to understand a specific group ... instruction called the instruction set. The work itself consists mostly ... calculations and data transport. Many types of personal computers can execute instructions in less than one-millionth of a second; supercomputers can execute instructions in less than one-billionth of a second. Each central processing unit has an internal clock (or system clock), which produces pulses ... a fixed rate to synchronise all computer operations. A single machine cycle instruction is made ... of a number of subinstructions, each of which must take ... least one clock cycle. The faster the clock speed, the more instructions it can execute.

3. Answer the following questions

1. How are the operations a microprocessor performs called?

2. What does the instruction set determine?

3. What computers are called compatible?

4. What are the functions of the CPU?

5. What units does the CPU consist of?

6. What operations can the ALU perform?

7. Where are the registers situated? What are their functions?

8. What operations does the control unit perform?

9. What is the speed at which a computer carries out its operations referred to?

10.What are the advances of nanotechnology?

11. What approach does greatly reduce electrical power and management costs?

12. How are computer chips divided?

4. Read the text

We can visualize the central processing unit as a clerk (the control unit) with a calculator (the arithmetic-logic unit). The clerk carries out computations with the aid of the calculator, following a detailed set of instructions (the program) written on a chalkboard (main memory). The clerk also uses the chalkboard for temporary data storage. Values to be saved are copied onto the board from the calculator; when they are needed later in the calculation, they are entered into the calculator from the board. Bv telephone (the bus), the clerk instructs assistants (drive controllers) to transfer data between filing cabinets (auxiliary memory) and the chalkboard. S'nce the assistants transfer data directly to and from the chalkboard, rather than going through the clerk for each transfer, their activities correspond to direct memory access. An assistant can also obtain data (input) from those for whom the calculations are being performed and supply them with

results (output).

When an assistant finishes an assigned task, he or she telephones the clerk for further instructions (interrupt request). After marking his or her place in the program, the clerk carries out a set of special instructions for answering telephone calls (interrupt handler). These instructions, which are also written on the chalkboard, specify what orders are to be given to the assistant. When the assistant has been properly instructed, the clerk resumes executing the program from the point at which it was interrupted when the telephone rang.

Now say with what functions of the CPU the given words can be compared:

a clerk a calculator

a set of instructions a chalkboard

telephone assistants

filing cabinets direct memory access

to obtain data to supply with results

further instructions

a set of special instructions for answering telephone calls