2684719
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Can anyone explain the fetch, decode and execute cycle in simple terms using keywords such as the components and registers? Thanks
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UWS
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(Original post by CountYourBlessings14)
Can anyone explain the fetch, decode and execute cycle in simple terms using keywords such as the components and registers? Thanks
It's been a few years but I'll try to help from what I remember.

It essentially is the process cycle of a computer's central processing unit in retrieving instructions from programs during the computer's operation.

Fetch:
- Instructions pulled from memory and stored in main memory.
- Program Counter (a register) stores the address location of the instruction
- Program Counter and instructions are placed in the Instruction Register (IR)
- Program Counter is incremented by 1

Decode:
- Decoder interprets the opcode/function of the instruction within the IR
- Here the data from main memory are placed into registers (MDR and MAR)

Execute:
- CPU will execute the instructions that are placed inside the registers

Store:
- Store the result in memory (if required)

Rinse and repeat...

As a basic diagram (ALU refers to the arithmetic logic unit)
Image

You can also use this site to help you
http://www.c-jump.com/CIS77/CPU/InstrCycle/lecture.html
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2684719
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(Original post by UWS)
It's been a few years but I'll try to help from what I remember.

It essentially is the process cycle of a computer's central processing unit in retrieving instructions from programs during the computer's operation.

Fetch:
- Instructions pulled from memory and stored in main memory.
- Program Counter (a register) stores the address location of the instruction
- Program Counter and instructions are placed in the Instruction Register (IR)
- Program Counter is incremented by 1

Decode:
- Decoder interprets the opcode/function of the instruction within the IR
- Here the data from main memory are placed into registers (MDR and MAR)

Execute:
- CPU will execute the instructions that are placed inside the registers

Store:
- Store the result in memory (if required)

Rinse and repeat...

As a basic diagram (ALU refers to the arithmetic logic unit)
Image

You can also use this site to help you
http://www.c-jump.com/CIS77/CPU/InstrCycle/lecture.html
Thank you so much!
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StreakyGamerTG
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The Code Is
Fetch:
- Instructions pulled from memory and stored in main memory.
- Program Counter (a register) stores the address location of the instruction
- Program Counter and instructions are placed in the Instruction Register (IR)
- Program Counter is incremented by 1

Decode:
- Decoder interprets the opcode/function of the instruction within the IR
- Here the data from main memory are placed into registers (MDR and MAR)

Execute:
- CPU will execute the instructions that are placed inside the registers

Store:
- Store the result in memory (if required)
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Hunnie1
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thanks for your help!!
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