1. Lesson 3 0x003 011 Hardware Components
Modified and presented by : Mohamed Zaki

2. Topics Simple Computer Architecture CPU Architecture CPU Registers
Executing instruction
Instruction set types
Memory Devices
Bus Systems
Input / Output Architecture

3. COMPUTER ARCHITECTURE Von Neumann Architecture
CPU/
Processor
Address Bus
Main
Memory
Data Bus
Control Bus
Input & Output Devices

4. Examples of CPUs Based on the manufacturer: Intel: Celeron Pentium I.
Pentium MMX. ( Multimedia Extension)
Pentium II.
Pentium III.
Pentium 4.
Centrino. ( Mobile Technology)
Core 2 DUO
Dual core
Quad core
Core i series (Laptop, Desktop, and Mobile Device Processors)
Xeon (Server and Workstation Processors)
AMD.
ARM
Dual Core A4,A5, A6
ARM Cortex-A9 MPCore (for iPad & iPhone and others)

5. CPU Architecture The clock: CPU: CPU Components:
CPU : Central Processing Unit. Also called Processor
CPU:
Is the part of a computer in which arithmetic and logical operations are performed and instructions are decoded then executed.
CPU Components:
ALU ( Arithmetic and Logic Unit)
CU (Control Unit)
Registers:
Are high speed & small in size temporary memory storage areas used during data manipulation ( calculation , comparison , etc..)
The clock:
It is a circuit for generating pulses that enable computer components to work in an ordered manner .

6. Main Memory / RAM / Primary Memory GENERAL PURPOS REGISTER
CPU Architecture
Main Memory / RAM / Primary Memory
ALU
101010
100001
001010
010100 ؟
Control Unit
GENERAL PURPOS REGISTER
CIR
MAR
Program Counter
Register
MBR
Bus : set of wires

7. CPU Registers General purpose registers: Special Purpose Registers:
are used to hold data before and after it is manipulated. Also used for many operation such addition, subtraction multiplication and logic operations
Special Purpose Registers:
Program counter PC:
it is loaded with the address in memory of the first instruction location of a program. After fetching, it is increased to point to the next location.
Memory Buffer register MBR:
all data and instructions pass in and out from the main storage through MBR.
Current instruction register CIR:
an instruction to be performed will be taken from the main storage via the MBR and placed in register IR.
Memory address register MAR :
prior to each transfer between the MBR and main storage , the exact source or destination of data in the main storage must be specified by MAR.

8. Executing a Software Program
The chart shows the steps that the CPU uses to execute a software
Copy PC contents into MAR & Initiate a memory read
Increment the PC
Copy the instruction
Which is in the MBR into CIR
Decode the CIR
Execute the instruction

9. Instruction set types Arithmetic and Logic inst. Set:
Each CPU has a set of instructions
Arithmetic and Logic inst. Set:
Such as addition, subtraction, multiplication, Increment, decrement, and logical operations, Such as add, sub,mul.
I/O instructions:
To transfer data between peripherals and memory, or between peripherals and accumulator, Such as mov
Processor reference instructions:
To stop the microprocessor activities. Such as halt.
Fetch (Load) and store instruction:
To transfer the data between accumulator and memory, Such as load
Memory reference instructions:
To access the memory during their execution, it is both Load + store instructions.
Transfer of control, or branch instruction: (Executing a Program)
To change the program sequence. Such as jmp

10. Memory Devices
Any memory is constructed from a collection of memory cells, each having unique address.
Each cell contains a combination of binary data(0 or 1).
Types of Memory:
RAM.
ROM.
Cache Memory.

11. Random Access Memory (RAM)
It also called Main or Primary Memory.
Programs & Data are stored there before processing .
The larger amount of RAM, the quicker programs will run.
More than one type of RAMs are used in modern PCs, like DRAM(Dynamic RAM) and SDRAM(Synchronous DRAM)
The data will be lost if the power is cut (Volatile Memory).

12. Read Only Memory (ROM) It holds the firmware program (BIOS).
It starts the POST “ power on self test” program
It contains auto-startup program that will load the necessary OS programs in RAM.
The information remains in the ROM when the computer turned off. ( Nonvolatile Memory)

13. The Differences between ROM and RAM:
ROM (Read Only Memory)
RAM (Random Access Memory)
Used to store part of O.S. by the factory.
ROM can be used for read only, we can't write or modify any thing on the ROM.
Not volatile memory (i.e. the information remains in the ROM when the computer turned off)
Used to store programs such as accounting program, games, word processor by the user.
We can use the RAM for read and write data.
Volatile memory (i.e. the information in the RAM is removed when the power turned off)

14. Cache Memory Is a small memory, located close to the processor?
Some processors are built with internal cache memory.
It has much shorter access time than the RAM. Therefore, it is used to hold instructions and data that has recently been accessed.
There are two types of cache memory: L1 and L2.
L1 ( Level 1) internal cache, built in with in the CPU.
L2 ( Level 2) external cache, built in with in the Motherboard, L2 is lager than L1. ( A+ Book p 131)

15. CPU, RAM, and Cache Diagram
Write through cache.
Write back cache.
Cache
RAM

16. Hard Disk

17. Hard Disk is a data storage device used for storing and retrieving digital information using rapidly rotating discs (platters) coated with magnetic material.
A magnetic heads arranged on a moving arm to read and write data to the surfaces.

18. Disk Organization Sector Track
Magnetic polarity determines the bit value (1,0)
Sector
Bit Value is 1
Bit Value is 0
Track
The Format Command is used to create Tracks and Sectors

19. Other Storage Devices
Flash Memory
DVD Disks
Magnetic Tapes

20. Storage Device Hierarchy
Size
Bytes
M Bytes
G Bytes
G – T Bytes
T Bytes
Speed
1 nsec
10 nsec
100 nsec
msec
sec -min
Registers
Cache
Main Memory
Flash Memory
Hard Disks
Magnetic Tapes
Hard Disk and Tapes have mechanical movements
Others do not have and called Solid Sate Devices (SSD)

21. Bus Systems (Connecting them together )
Is a collection of parallel electrical lines which connect the computer components.
The buses used to transfer:
Data signals.
Address signals.
Control signals.
Power.

22. Bus Systems Address Bus Size of memory that can be addressed= 2L
The address bus is the set of wires carrying the addressing information used to describe the memory location, which the data is being sent or retrieved.
The size of the address bus indicates the maximum amount of RAM that a chip can address.
Size of memory that can be addressed= 2L
Were L = No. of Lines in address bus ( Size of address bus)

23. Bus Systems Address Bus Size of address bus Size of memory 1 21 16
216 ~= 64 KB 2
22 =4 20
220 ~= 1 MB 3
23=8 30
220=1 GB 4
24 =16 32
232=4 GB
: : 10
210 =1024=1KB 11
211=210x21=2 KB 12
212=210x22=4 KB

24. Bus Systems
Address Bus
Examples:
1) how many addresses can be built by 3 digits (3 lines):
2n = 23 = 8 address bus locations from
( 000 to ) 2): how many addresses can be built by 3 digits (3 lines):
2n = 23 = 8 address bus locations from ( 000 to 111 )

25. Input / Output Architecture
The computer has the ability to send and receive data to and from other devices.
We can transfer data in parallel and serial lines.
When the CPU wishes to send data to a particular I/O devices it places a unique identity code ( address ) onto the address line.
Only the device that recognizes that code will respond to the command that is placed on the control line.