1. Interaction between CPU, memory &
input/output device, functions of CPU
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2. Objective
On completion of this period, you would be able
to learn:
Blocks of Computer System
Interaction between functional blocks
Functions of CPU
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3. Recap
What is a computer?
It is an electronic device which processes the data
Functional units of a computer
Input unit
Memory unit
ALU
CU
Output unit
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4. Prerequisites
What are parts of the computer?
Input Unit
Memory Unit
CPU
Output Unit
What is CPU?
Central Processing Unit
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5. Interaction between functional blocks
data To user
INPUT UNIT
INPUT UNIT MEMORY UNIT
MEMORY UNIT OUTPUT UNIT
OUTPUT UNIT
(Result)
instruction read write
operand result
CONTROL UNIT
CONTROL UNIT ALU
ALU
Control
signals
___ data flow
------Control flow
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6. Interaction between Functional Blocks
Data is supplied to the computer through an input
device.
The data is then transferred to memory under the
supervision of the control unit.
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7. Interaction between functional blocks
(contd)
Each instruction is interpreted before execution
Control unit informs the ALU of the precise
operation to be performed and
Directs the transfer of operands to the ALU
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8. Interaction between functional blocks (contd)
The ALU then performs all calculations and
comparisons needed
And the results are then passed unto the
memory unit, from there to the output unit
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10. CPU
CPU is the heart and brain of a computer.
It receives data as input.
Follows instruction, and processes data
accordingly.
Presents the information as out put to the user.
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11. CPU (contd)
Its primary function is to execute programs.
it controls & coordinates all components such as
memory, input and output devices.
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13. CPU (Central Processing Unit)
ALU (Arithmetic & Logical Unit)
It performs two types of operations
1. Arithmetic Operations.
2. Logical Operations.
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15. Logical Operations
Logical AND
Logical OR
Logical NOT
Logical EXCLUSIVE OR
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16. CU (Control Unit)
Controls the operations that takes place in
various parts of a computer by sending
electronic signals.
Supervises the flow of data in various parts of
computer such as input device, output device,
and memory devices.
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18. Functions of CPU
CPU performs everything in binary form
It takes the information and process it
according to instructions.
It performs all calculations.
It takes all decisions.
It controls all units of computer.
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19. Summary
In this class, you have learnt about
Blocks of CPU
Functions of CPU
Interaction among the functional
blocks
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20. Questions
1. Explain the interaction between CPU, memory
and I/O devices?
2. Describe the functions of CPU?
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21. Quiz
1. The control unit, together with the ALU
and memory unit, form
a. control unit
b. memory
c. CPU (central processing unit)
d. ALU
Answer: c
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22. Quiz (Contd...)
2. The program’s instructions and data are
transferred under the control of
a. CPU
b. Control Unit
b. ALU
d. Memory Unit
Answer: b
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23. Quiz (Contd...)
3. ALU handles
a. arithmetic operations
b. logical operations
c. arithmetic operations and logical operations
d. None of the above
Answer: c
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24. Assignment
• Open a CPU cabinet with the help of your
teacher (expert), and try to understand the
connections and working of various components
in side.
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