1. Chapter 2 content Basic organization of computer What is motherboard
What is cpu
Components of CPU ( ALU, CU, MU<cache>)
Primary Storage (RAM)
Secondary Storage (Hard Disk, CD , Fash drive)
What is ROM
What is Computer Bus ( Data Bus, Control Bus, Address Bus)
Input Devices and Ouput Devices

2. BASIC ARCHITECTURE OF COMPUTER SYSTEM CHAPTER - II
Basic Organization of a Computer System is called Computer Architecture.
Different computer have different architecture.
But, basic organization remains the same for all computer systems.
E.g. CPU, MEMORY, INPUT/OUTPUT Devices
Motherboard: In personal computers, a motherboard is the central printed circuit board (PCB) and in many modern computers and holds many of the crucial components of the system, providing connectors for other peripherals (input/output devices).

3. Hardware Devices Analogy: A Paper-Based Office
Register Storage
Output
Primary Storage
Secondary Storage
Input
Logically there is no difference between a Computer and a Human
Principles of Information Systems, Eighth Edition

4. A Computer Hardware System
Figure 3.1: Hardware Components
Principles of Information Systems, Eighth Edition

8. Microprocessor /Processor/ CPU
The Central Processing Unit (CPU) carries out all the computer program instructions.
Choosing the right CPU has a great impact on performance.
Two very popular choices of CPU for use in a PC are:
The Pentium series from Intel
The Athlon series from AMD

9. CPU…. Continue CPU stands for central processing Unit.
Each CPU has a set of pins through which all its communication takes place with the other devices.
CPU consists of two units
ALU (Arithmetic and Logic Unit)
CU (Control Unit)
CPU located on motherboard.

10. 1. Arithmetic and Logic Unit (ALU)
All arithmetic and logical operations are performed in ALU.
Asthmatic Operations such as
(+, *, -, %, /)
Logical Operations such as
(>, <, >=, <=, !=, =, ==)
No processing occurs in primary storage.
Data move from primary storage to ALU or vice versa.

11. Control Unit (CU) Act as a supervisor of the computer.
The control unit is the circuitry that controls the flow of information through the processor, and coordinates the activities of the other units within it.
In a way, it is the "brain within the brain", as it controls what happens inside the processor, which in turn controls the rest of the PC.
The control unit is one of the most important parts of a microprocessor for the reason that it is in charge of the entire process, that is the machine cycle. The CPU deals with each instruction it is given in a series of steps. Each step is repeated for each instruction.

12. Control Unit (CU)
This series of steps is called the machine cycle (fetch-decode-execute cycle). It involves:
fetching an instruction from memory;
decoding the instruction;
transferring the data;
executing the instruction.
The control unit makes sure that all of those actions are carried out. It also manages all the other components on the CPU.

13. Memory Unit (MU) CPU has its own memory to store data. (Cache)
Like L1, L2, L3 (A shared Memory )
Instructions are also stored in this memory/CPU registers.
These are the fastest storage area in a computer.

14. MU vs Mail Box Example
The location in memory for each instruction and each piece of data is identified by an address.
That is, each location has an address number, like the mailboxes in front of an apartment house. And, like the mailboxes, the address numbers of the locations remain the same, but the contents (instructions and data) of the locations may change. That is, new instructions or new data may be placed in the locations when the old contents no longer need to be stored in memory.

15. MEMORY A typical computer contains numerous types of memory including
In computing, memory refers to the physical devices used to store programs (sequences of instructions) or data (e.g. program state information) on a temporary or permanent basis for use in a computer or other digital electronic device.
A typical computer contains numerous types of memory including
RAM (Random Access Memory)
ROM (Read Only Memory)
Virtual Memory

16. RAM
RAM is the most common type of memory found in computers and other devices, such as printers.
There are two different types of RAM: DRAM (Dynamic Random Access Memory) and SRAM (Static Random Access Memory).
The two types differ in the technology they use to hold data, with DRAM being the more common type. In terms of speed, SRAM is faster. DRAM needs to be refreshed thousands of times per second while SRAM does not need to be refreshed, which is what makes it faster than DRAM. DRAM supports access times of about 60 nanoseconds, SRAM can give access times as low as 10 nanoseconds.
Despite SRAM being faster, it's not as commonly used as DRAM because it's so much more expensive.
Both types of RAM are volatile, meaning that they lose their contents when the power is turned off.
In common usage, the term RAM is synonymous with main memory, the memory available to programs.

17. ROM
ROM (read-only memory) refers to special memory used to store programs that boot the computer and perform diagnostics. Most personal computers have a small amount of ROM (a few thousand bytes). In fact, both types of memory (ROM and RAM) allow random access. To be precise, therefore, RAM should be referred to as read/write RAM and ROM as read-only RAM.

18. Read Only Memory (ROM) Types
There are five basic ROM types:
ROM - Read Only Memory
PROM - Programmable Read Only Memory
EPROM - Erasable Programmable Read Only Memory
EEPROM - Electrically Erasable Programmable Read Only Memory

19. Each type has unique characteristics, but all types of  ROM memory have two things in common:
Data stored in these chips is non-volatile -- it is not lost when power is removed.
Data stored in these chips is either unchangeable or requires a special operation to change. 

20. Computer/System Bus
A collection of wires which data is transmitted from oe part of a computer to another.
Think, Bus as a highway
The size of a bus, known as its width , for example 16-bit bus
Internal Bus .

22. Computer Bus …… Continue
Data needs to move around the computer, for example:
The CPU needs to move information in and out of memory
Data needs to move between the hard disk and the CPU.
Data needs to move between the graphics card and the CPU
Data needs to move between the CDROM / DVD and the CPU
The way that data is moved from one place to another is via a 'bus'.
A 'bus' is a set of wires or copper tracks that are built into the motherboard. 

23. A 16 bit bus can transfer 16 bits in one cycle - 1 bit per wire.
A bus usually contains between 1 to 64 wires (or more), the number of wires equals the number of  'bits' that can be transferred in one clock cycle.
An 8 bit bus has 8 wires - it can transfer 8 bits in one go, with 1 bit on each wire.
A 16 bit bus can transfer 16 bits in one cycle - 1 bit per wire.
Current PCs have 32 bit buses and the newer generation are going to use 64 bit wide buses.

24. Types of Computer Bus Data Bus Address Bus Control Bus
Used to carry data signals
E.g numbers which we want to add or the string which we want to compare.
Transfer data from main memory (Ram) to CPU and vice versa or other part of computer.
Address Bus
Used to carry address signals
E.g address of memory location or a port(interface – where an input or output device is attached.
Control Bus
It used to carry control signals
E.g read/write , enable / disable etc.