This document discusses the components and functions of a basic computer system. It lists five group members and then describes how the central processing unit (CPU), memory, and input/output devices work together. The CPU consists of a control unit and arithmetic logic unit (ALU) and follows a four-step machine cycle of fetch, decode, execute, and store to process instructions. The control unit directs this cycle and communicates with the ALU and memory, while the ALU performs arithmetic and logical operations.

1. Member Of Group
 Hestu Aji Prihanditya (4611414007)
 Devi Tri Widyanti (4611414014)
 M. Anbiya Nur Islam (4611414022)
 Feroza Rosalina Devi (4611414024)
 Kusmahendra Agung Pambudi (4611414037)

2. Storage
(Pimary/Secondary Memory)
Storage
(Pimary/Secondary Memory)
Input OutputProcesorProcesor
HOW THESE COMPUTER WORKS?
Monitor,
Printer
CPU must be connected to input device, output
device and storage device to carry out the
activities
DataData InformationInformation
INFORMATION PROCESSING CYCLE
DataData InformationInformation

4. The Central processing Unit
• The CPU interprets instructions to the computer, performs
the logical and arithmetic processing operations, and causes
the input and output operations to occur.
• Consists of hundreds of thousands or millions of electronic
circuits.
• In today's PCs the CPU is contained in a single silicon chip
called a microprocessor chip
• It is considered the “brain” of the computer.
• Also called the CPU as PROCESSOR &
MICROPROCCESSOR

5. Intel Pentium D AMD Athlion 64 Intel Pentium M

6. Pentium D
Pentium I-IV
Pentium M
Celeron
Core i7
Core 2 Duo

7. AMD
Athelon 64 X2
Athelon 64
Turion 64
Sempron

8. Processor / CPU
The Control processing unit (CPU) controls all
activities within the system. For every
instruction, the control unit repeats a set of four
basic operations called the MACHINE
CYCLE
a CPU consists of two subcomponents:-
1. Control Unit (CU)
2.Arithmetic Logic Unit (ALU).

9. Control Unit
Control Unit’s main function in CPU to process data.
1. The Control Unit extracts instructions from
memory and decodes and executes them.
2. Manages all resources of a computer
3. Manages a 4-step basic operation which is called a
machine cycle or processing cycle.

10. The Arithmetic-Logic Unit and Control
Unit
• An arithmetic logic unit (ALU) and control unit is one
of the core components of all central processing units.
• Arithmetic operations: e.g., add, subtract, multiply, divide,
square root, cosine, etc.
• Logical operations: e.g., compare two numbers to see
which is greater, check whether a true/false statement is
true, etc.
• Comparison operation : e.g:AND, OR, NOT, NAND,
NOR, XOR and equacalence (=)

11. Signals
An ALU has a variety of input and output nets, which are the
shared electrical connections used to convey digital signals between
the ALU and external circuitry. When an ALU is operating, external
circuits apply signals to the ALU inputs and, in response, the ALU
produces and conveys signals to external circuitry via its outputs.
Data
A basic ALU has three parallel data buses consisting of two
input operands (A and B) and a result output (Y). Each data bus is a
group of signals that conveys one binary integer number.

12. Opcode
The opcode input is a parallel bus that conveys to the ALU an
operation selection code, which is an enumerated value that specifies
the desired arithmetic or logic operation to be performed by the
ALU.
Status
The status outputs are various individual signals that convey
supplemental information about the result of an ALU operation.
These outputs are usually stored in registers so they can be used in
future ALU operations or for controlling conditional branching.

13. General-purpose ALU commonly have status signals such as:
a. Carry-out, which conveys the carry resulting from an addition
operation, the borrow resulting from a subtraction operation, or the
overflow bit resulting from a binary shift operation.
b. Zero, which indicates all bits of the Y bus are logic zero.
c. Negative, which indicates the result of an arithmetic operation is
negative.
d. Overflow, which indicates the result of an arithmetic operation has
exceeded the numeric range of the Y bus.
e. Parity, which indicates whether an even or odd number of bits on
the Y bus are logic one.

14. Function of Control Unit
• The control unit directs the entire computer system to carry out
stored program instructions.
• The control unit must communicate with both the arithmetic logic
unit (ALU) and main memory.
• The control unit instructs the arithmetic logic unit that which
logical or arithmetic operation is to be performed.
• The control unit co-ordinates the activities of the other two units
as well as all peripherals and auxiliary storage devices linked to
the computer.

15. Machine Cycle
15
FETCHING
EXECUTING
STORING DECODING

16. Machine Cycle
4 step in Machine Cycle :
• Step 1: Fetch – retrieve an instruction from memory
Fetch is dealing with retrieving an instruction from main
memory. After an instruction is fetched, the PC is
incremented in memory locations.
•Step 2: Decode – translate instruction in a form ALU can
understand (command )
Decoder fetches data is broken up into parts which are
related to other portions of the CPU, this is termed as
opcode, indicates which operation to perform.

17. Step 3: Execute – Carry out instruction
After decode steps, the execute step is performed. During this step,
various portions of the CPU are connected so they can perform the
desired operation.
Step 4: Store – copy results to Memory

18. Processor
Control Unit
MEMORY
ALU
How it’s work ?
Step 1. Fetch
Calls an instruction into
memory. User want to
calculate 2 +2
Step 2.
Decode
Translate
instruction into
commands (to
binary form)
Eg : 1110000
Step 4. Store
Write result to memory
Step 3. Execute
Does the decoded
instruction
Add 2+2
 Four operations of the CPU comprise a machine cycle

19. Factors Affecting Processing Speed
• Clock rate of the CPU
• Computer word size
• Bus speed
• Main memory size
• Cache memory size
• instruction set complexity
• Number of processing units

20. TERIMAKASIH