1.2.1
CISC & RISC
CISC & RISC Processors
CISC & RISC Processors
Processors usually fall under one of two categories: CISC or RISC.
![Illustrative background for CISC](https://image-v2.cdn.app.senecalearning.com/2018-06/73312df4-77a7-4995-890c-01991e5f528f/shutterstock_1008152356,h_400,q_80,w_640.jpg)
![Illustrative background for CISC ?? "content](https://image-v2.cdn.app.senecalearning.com/2018-06/73312df4-77a7-4995-890c-01991e5f528f/shutterstock_1008152356,h_400,q_80,w_640.jpg)
CISC
CISC
- CISC stands for Complex Instruction Set Computer.
- CISC processors have a large instruction set built into it.
![Illustrative background for CISC instruction set](https://image-v2.cdn.app.senecalearning.com/courseImages/chemistry/7.2.3 Synthetic and naturally occurring polymers/checklist-1766064_640-min,h_400,q_80,w_640.png)
![Illustrative background for CISC instruction set ?? "content](https://image-v2.cdn.app.senecalearning.com/courseImages/chemistry/7.2.3 Synthetic and naturally occurring polymers/checklist-1766064_640-min,h_400,q_80,w_640.png)
CISC instruction set
CISC instruction set
- The large instruction set allows programmers of assembly language to use fewer instructions as the instruction set built-in would deal with the additional needed steps.
- Most of the built-in instructions are made up of multiple simple instructions.
- Only about 20% of the built-in instructions were used in the average program.
![Illustrative background for RISC](https://image-v2.cdn.app.senecalearning.com/2020-08/2a39a800-4632-40aa-ae93-c843fa621e49/gpu-cpu,h_400,q_80,w_640.jpg)
![Illustrative background for RISC ?? "content](https://image-v2.cdn.app.senecalearning.com/2020-08/2a39a800-4632-40aa-ae93-c843fa621e49/gpu-cpu,h_400,q_80,w_640.jpg)
RISC
RISC
- RISC stands for Reduced Instruction Set Computer.
- A RISC processor has a small number of essential instructions built-in.
- Each of these instructions can be completed in a single clock cycle.
- This reduced instruction set means assembly programmers have to code more lines of code to achieve more complex results.
![Illustrative background for CISC vs RISC](https://image-v2.cdn.app.senecalearning.com/2019-05/18db7257-a020-4f61-81ab-037f894914a3/opposite-thumb-,h_400,q_80,w_640.jpg)
![Illustrative background for CISC vs RISC ?? "content](https://image-v2.cdn.app.senecalearning.com/2019-05/18db7257-a020-4f61-81ab-037f894914a3/opposite-thumb-,h_400,q_80,w_640.jpg)
CISC vs RISC
CISC vs RISC
- RISC processors have a library of simple efficient instructions whereas a CISC processor has a large library of complex instructions made up of simpler instructions.
- A RISC processor has few addressing modes where a CISC processor has many addressing modes.
- CISC processors are more expensive than RISC processors.
1Components of a Computer
1.1Structure & Function of the Processor
1.2Types of Processors
2Software & Software Development
2.1Systems Software
2.2Applications Generation
2.3Software Development
3Exchanging Data
3.1Compression, Encryption & Hashing
3.3Networks
4Data Types, Data Structures & Algorithms
4.1Data Types
5Legal, Moral, Cultural & Ethical Issues
5.1Computing Related Legislation
6Elements of Computational Thinking
6.1Thinking Abstractly
6.2Thinking Procedurally
6.3Thinking Logically
7Problem Solving & Programming
7.1Programming Techniques
7.2Programming Construction
Jump to other topics
1Components of a Computer
1.1Structure & Function of the Processor
1.2Types of Processors
2Software & Software Development
2.1Systems Software
2.2Applications Generation
2.3Software Development
3Exchanging Data
3.1Compression, Encryption & Hashing
3.3Networks
4Data Types, Data Structures & Algorithms
4.1Data Types
5Legal, Moral, Cultural & Ethical Issues
5.1Computing Related Legislation
6Elements of Computational Thinking
6.1Thinking Abstractly
6.2Thinking Procedurally
6.3Thinking Logically
7Problem Solving & Programming
7.1Programming Techniques
7.2Programming Construction
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