What’s inside a PC system?
The nerve centre of a PC is the ------------------------- or CPU. This unit is built into a single
_________________ – an _________________ (1) which executes program instructions and
supervises the computer’s overall operation. The unit consists of three main parts:
i/ ____________________, which examines the instructions in the user’s program, interprets each
instruction and causes the circuits and the rest of the components – disk drives, monitor, etc. – to be
activated to execute the functions specified;
ii/ __________________ (ALU), which performs mathematical calculations (+, -, etc.) and logical
operations (and, or, etc.);
iii/ __________________, which are high-speed units of memory used to store and control
information. One of these registers is ________________(PC) which keeps track of the next
instruction to be performed in the main memory. Another is ________________(IR) which holds the
instruction (2) that is currently being executed.
One area where microprocessors differ is in the amount of data, the number of bits, (3) they can
work with at a time. There are 16, 32 and 64-bit processors. The computer’s__________________ is
evolving so quickly that the new 64-bit processors are able to address 4 billion times more
information than a 32-bit system
The programs and data which pass through the central processor must be loaded into
______________________ (also called the internal memory) in order to be processed. Thus, when
the user runs an application, the microprocessor looks for (4) it on secondary _______________
(disks) and ____________ a copy of the application into the RAM area. ______ (random access
memory) is temporary, i. e. (5) its information is lost when the computer is turned off. However, the
_________section (read only memory) is permanent and contains instructions needed by the
processor.
Most of today’s computers have internal _________________ (6) that allow users to
___________adapters or expansion boards. Popular adapters include high-resolution graphics
boards, memory expansion boards, and internal modems.
The power and performance of a computer is partly determined by the speed of its microprocessor.
A clock provides pulses at fixed intervals to measure and synchronize circuits and units. The clock
speed is measured in MHz (megahertz) or GHz (gigahertz) and refers to the frequency at which pulses
are emitted. For example, a CPU running at 1,600 MHz (1,600 million cycles per second) will enable
the computer to handle the most demanding applications.
Exercise 2
. Read the text above and then sentences 1 to 8. Decide if the sentences are true or false, and correct
the false ones to make them true
. 1. The CPU directs and coordinates the activities taking place within the computer system.
2. The arithmetic logic unit performs calculations on the data.
3. 32-bit processors can handle more information than 64-bit processors.
4. A chip is an electronic device composed of silicon elements containing a set of integrated circuits.
5. RAM, ROM and secondary storage are the components of the main memory.
6. Information cannot be processed by the microprocessor if it is not loaded into the main memory.
7. “Permanent” storage of information is provided by RAM (random access memory).
8. The speed of the microprocessor is measured in gigahertz or megahertz. One GHz is equivalent to
one thousand MHz One MHz is equivalent to one million cycles per second.
Task3:
What do the words in bold print refer to.
1. ... which executes program instructions and supervises …..
2. ... the instruction that is currently being executed, …
3. ... the amount of data – the number of bits – they can work with at a time
4. ... the microprocessor looks for it on ...
5. … its information is lost when the computer is turned off.
6. ... expansion slots that allow users to install adapters or expansion boards
Task01: choose the correct word
Microprocessor chip –control unit-central processing unit-integrated circuit –
registers –arithmetic logic unit-instruction register-program counter-main
memory –internal architecture- registers-transfers- storage devices-Rom-
expansion slots -Ram-INSTALL.
