Journey of Computer and

1. Journey of Computer and Information Technology Volume 1 2.7 Central Processing Unit

2. A. Basic Components of a Central Processing Unit (CPU) a single microprocessor  Many magazines introduce the latest models of CPUs

3. Three Basic Components of CPU (a) Control Unit (CU)  extract the instructions from the main memory, decodes them and executes them (b) Arithmetic and Logic Unit (ALU)  perform all arithmetic computations and all logic operations (c) Register  store temporary data for use

4. CPU Memory chips Bus B. Bus Connections a collection of wires through which data is transmitted from one part of a computer to another

5. Three Types of Buses (a) Address bus  identify particular memory addresses (b) Control bus  control instructions between the CPU and other internal devices (c) Data bus  carry actual data that is being processed

6. Free the operating system and its application programs from learning the hardware addresses so they need not be changed when the device details change. CPU BIOS Boot up a computer system. Manage data transfer between the operating system ad attached hardware devices. Determine all attachments are in place and optional. Load the operating system (from the hard disk or floppy disk) into RAM. C. Functions of the CPU (1) Booting Up a Computer System

7. Registers Control Unit Main Memory Registers Registers ALU 0000 LDA 2000 0004 ADD 2004 0008 JPN 300C 000C SUB 2008 Registers (2) Running Program Instructions

8. Discussion Intel Celeron, Intel Pentium and AMD are three common types of CPU. State their differences and compare their advantages and disadvantages.

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