Configuring A Computer - 1.6 - 1.7

1.6 EVOLUTION OF MICROPROCESSOR:

            i)Microprocessor is an integrated circuit on a single chip.

           ii)Single micro processor is equivalent to mainframe computers.

          iii)Some microprocessor companies are Intel, Motorola, Advanced  Micro Devices (AMD), and             Cyrix..

    iv)Intel Corporation is the largest manufacturer of microchips in the world.

         Manufactured Year with the model.

Model                           Year

4004                                1971

8008                              1972

8080                                1974

8086                                1978

80286-80486                 1982 - 1989

Pentium 1 – Pentium 4 1993-2000

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1.7.1 ,MOTHER BOARD

1.7.1.1  Define Motherboard.

              The main circuit board of the computer which contains the CPU, memory, expansion slots, bus,              and video controller. Also called as system board.

 Specify The Components of Motherboard.

1.7.2.1 BUS :  i)a set of electrical conducting lines, through which binary information is transferred.

ii)Types are, internal and External.

iii)The internal bus can be connects the different components inside the case: The CPU, system memory, and all other components on the mother board. Also called as system bus.

iv)The external bus connects the different external devices, peripherals expansion slots, I-O ports and drive connections to the rest of the computer.

1.7.2.2 Communication of ports or I-O   ports:

            Port :  A   socket on the back of the computer used to connect external devices to the computer.

a)      Serial ports :

i)Devices like  mouse, modem, older printers can be attached.

ii)Transfers data serially one bit at a time.

iii)Are also called as RS-232-C  ports or COM  ports.

b)      Parallel    ports

i)Devices like printers and some types of external storage devices can be attached.

ii) Transfers data on parallel path with 8 bits at a time.

iii)Are also called as the printer port, or LPT1 .

          c)  SCSI(small computer system interface)port

i)Devices like hard disks ,high end scanners and CD-ROM drives can be attached.

ii)Transfers data fastly.

          d)  USB (universal Serial Bus)

i)Devices like audio players, joysticks, keyboards, modems, scanners, and printers with USB

can be attached.

ii)a plug and play interface to attach add-on devices.

iii)devices can be added without adding an adapter card or restarting the system.

a)      Game Port

i)Gaming devices like joysticks  can be attached.

ii)Provides for more intense gaming actions.

1.7.2.3 MOTHERBOARD SLOT OR EXPANSION SLOT

            Explanation slot:

           i)The area of the motherboard into which expansion boards are inserted.

ii) An ISA (industrial standard architecture) slot is a 16 bit slot. A PCI slot is 32 bits.  The AGP (accelerated graphics port) slot is for inserting graphics card which make graphics application run faster.

1.7.2.4 Input device ports

            i)All PCs have a keyboard   port connected directly to the mother board.

          ii)Keyboard and mouse are connected with ps/2 connector.

1.7.2.5 RAM slots:

           i) Random Access Memory stores  programs and data currently being by the CPU.

           ii)Types of sockets to install the memory are SIMM(Single inline memory module) sockets and DIMM(Dual inline memory module) sockets.

1.7.2.6 Hard disk controller:

           i) A controller is a device that is responsible for controlling data flow.

           ii)Hard  drive controller is responsible for the following,

1.       Receiving information from the processor and converting or interpreting the information into signals that the hard disk can understand.

2.      Sending information back to the processor and converting the information into signals that the processor can understand.

            iii)The first major standard developed for hard disk controllers is the IDE(integrated digital electronics) standard.

1.7.2.7 : Floppy disk controller :

               Connects the floppy drive to the mother board.

1.7.2.8  Processor slot

                        The processor is usually the largest chip on the system board.

1.7.2.9  Cache memory :

i)Cache memory increases performance by storing frequently used data.

ii)It is faster than RAM.

iii)Types are,

    L1(level-1) cache : cache that is integrated within the processor.

    L2 (level-2) cache: cache that is located outside the processor, like on the mother board.

1.7.2.10 BIOS chip

i)The basic  input output system (BIOS) is low level program code that allows all the system devices to communicate with one another.

ii)Has code which controls the boot process of the system.

iii)Has code which performs  power on self test(POST).

iv)Calls on the master boot record which will load an operating system.

 1.7.2.11 CMOS battery

i)Complementary metal oxide semiconductor (CMOS).

ii)CMOS is a listing of system components, such as the size of the hard disk , the amount of RAM, and the resources used by the serial  and parallel ports.

iii)CMOS RAM should not lose its charge. If so, its content will be lost.

Configuration of Computer - 1.2 - 1.5

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CONFIGURING A COMPUTER

CHAPTER-1

1.2   REVIEW OF THE BLOCK DIAGRAM OF A COMPUTER:

            A  Computer is designed using four basic units. They are:

1.       Input data

2.      Central processing  unit (CPU)

a.        Control unit

b.      Arithmetic and logic unit

3.      Memory  unit

4.      Out put unit

1.       Input unit: 

i)The Input unit basically links the external world or environment to the computer system. .

ii)The keyboard and mouse of a computer are the most commonly used input devices.

2.      Central processing unit (CPU):

i)To interpret the instructions in the program and execute them one by one.

The units are,.

a)      Control unit: Transfers the program instructions and data between various units.

b)      Arithmetic and logic unit (ALU): Arithmetic operations like (+, -,*,^,/), logical operations like(AND, OR, NOT) and relational operations like (<, >,<=,>=) are performed  in this  unit.

c)      Registers: To store the intermediate data.

3.      Memory unit: To store input , intermediate results and the output.

4.      Output data: To print or to display the results.

1.3 GENERAL STRUCTURE OF A CPU:

                       

i.        Program counter: To keep track of the memory address of next instruction which has to be executed.

ii.       Memory address register: i) specifies the address to memory where information can be found  ii)To point to a memory location where information is to be stored.

iii.      Memory data register / Memory buffer register: An interface between the central processing unit and memory.

iv.     Instruction register (IR): The instruction register holds the instruction until it can be decoded.

v.      Timing and control unit (TCU):i) The operations of the CPU should always be performed in a proper sequence.

ii)The timing and control unit is used to generate all internal and external control signals which carries the execution.

vi.    Instruction decoder (ID): i)An electronic hard ware which decodes the instruction .

ii)The instructions are further broken down into a set of micro operations so that they can be executed directly.

vii.  Arithmetic logic unit (ALU):  i)performs arithmetic, logical and relational operations.

ii)Results will be transferred back to the accumulator.

viii.     Accumulator (ACC): To store the initial, the intermediate and the final result of an instruction.

1.4 HOW INSTRUCITON IS EXECUTED?

            A basic instruction execution cycle can be broken down into the following steps:

1.       Instruction cycle

2.       Execution cycle

1.      Instruction cycle:

a.      Instruction Fetch

i)Program Counter holds the memory address of next instruction.

ii)Address transferred to Memory Address Register.

iii)Data transferred to Memory Data register based on CPU’s read request.

iv)Data transferred to Instruction Register.

v)Program Counter incremented to point out address of next data.

b.      Instruction decode:

i)Determines the type of instruction.

ii)Selecting signals accordingly.

2.      Execution cycle: i)Data will be processed by CPU and get stored in accumulator temporarily. ii)Then transferred to the main memory.

1.5 FACTORS AFFECTING THE PROCESSING SPEED

             

i.        Register size : i)Normally the register size in the processor will be of 32 bits.

ii)Smaller size  will reduce the speed.

ii.      Memory size: i)The  amount of RAM or main memory can also affect the speed.

ii)The size of the RAM may vary from 64 megabytes to 4 gigabytes.

iii.    Clock speed: i)The computers system clock sets the pace for the CPU by using a vibrating quartz crystal.

ii)Fast clock  can process more instructions.

. For example 1000MHZ processor performs 1000 million instructions per second.

iv.    Data bus capacity : i)The width of the data bus determines how many bits can be transmitted at a time between the CPU and other devices.

ii)width of the address bus give the amount of address space, which can be accessed at any instance of time.

v.       Cache memory  : i) A  high speed memory that contains the most recent data.

ii)  The cache memory  normally varies 512KB to 1MB.

iii)The more the cache the execution speed will be faster.

vi.    Instruction set: i)The set of basic commands the processor can understand and execute is called the instruction set.

ii)More the number of bits in a processor, the larger the instruction set.

For example, a 16- bit processor has larger instruction set than 8-bit processor.

vii.  Heat and heat dissipation: i)When the processor runs it generates heat and becomes too hot. ii)Installing an adequate cooling system is the solution