3.1.3
Registers of the Central Processing Unit (CPU)
Registers of the Central Processing Unit (CPU)
Registers of the Central Processing Unit (CPU)
Registers that have a predetermined purpose in the central processing unit are known as special purpose registers.
![Illustrative background for Program Counter (PC)](https://image-v2.cdn.app.senecalearning.com/2018-03/c77cef8f-f89c-4652-9850-73d3e25e1400/shutterstock_96602686,h_400,q_80,w_640.jpg)
![Illustrative background for Program Counter (PC) ?? "content](https://image-v2.cdn.app.senecalearning.com/2018-03/c77cef8f-f89c-4652-9850-73d3e25e1400/shutterstock_96602686,h_400,q_80,w_640.jpg)
Program Counter (PC)
Program Counter (PC)
- Holds the memory location address of the next instruction to be performed by the CPU.
![Illustrative background for Accumulator (ACC)](https://image-v2.cdn.app.senecalearning.com/2018-08/464298b9-9086-4c79-807f-556d74d95868/counting,h_400,q_80,w_640.jpeg)
![Illustrative background for Accumulator (ACC) ?? "content](https://image-v2.cdn.app.senecalearning.com/2018-08/464298b9-9086-4c79-807f-556d74d95868/counting,h_400,q_80,w_640.jpeg)
Accumulator (ACC)
Accumulator (ACC)
- Holds the result of calculations and operations performed by the arithmetic logic unit (ALU).
![Illustrative background for Memory Address Register (MAR)](https://image-v2.cdn.app.senecalearning.com/2018-06/f5ce1516-cbc4-4b4d-a8c5-bbc41cdbd3fc/reg,h_400,q_80,w_640.jpeg)
![Illustrative background for Memory Address Register (MAR) ?? "content](https://image-v2.cdn.app.senecalearning.com/2018-06/f5ce1516-cbc4-4b4d-a8c5-bbc41cdbd3fc/reg,h_400,q_80,w_640.jpeg)
Memory Address Register (MAR)
Memory Address Register (MAR)
- Holds the address of the location in memory where data is to be retrieved or stored.
![Illustrative background for Memory Data Register (MDR)](https://image-v2.cdn.app.senecalearning.com/2018-07/696268e7-bbc5-4981-bd2d-939f0ee913d2/MDR-Register-Computer-Computing-,h_400,q_80,w_640.jpg)
![Illustrative background for Memory Data Register (MDR) ?? "content](https://image-v2.cdn.app.senecalearning.com/2018-07/696268e7-bbc5-4981-bd2d-939f0ee913d2/MDR-Register-Computer-Computing-,h_400,q_80,w_640.jpg)
Memory Data Register (MDR)
Memory Data Register (MDR)
- Holds the data that has been retrieved from memory, or that is about to be stored in memory.
1Computational Thinking & Algorithms
1.1Computational Thinking
1.2Algorithms
1.2.1Algorithms
1.2.2Pseudocode
1.2.3Flow Diagrams
1.2.4Logical Reasoning & Debugging
1.2.5Reading Algorithms
1.2.6Correcting Algorithms
1.2.7Complete the Algorithm
1.2.8Search Algorithms
1.2.9Linear Search
1.2.10Binary Search
1.2.11Sort Algorithms
1.2.12Bubble Sort
1.2.13Insertion Sort
1.2.14End of Topic Test - Algorithms
2Programming
2.1Programming Fundamentals
2.1.1Variables & Constants
2.1.2Comments
2.1.3Input & Output
2.1.4Arithmetic Operators
2.1.5Relational Operators
2.1.6Boolean Operators
2.1.7Sequence
2.1.8Selection
2.1.9Iteration
2.1.10Subroutines
2.1.11Scope
2.1.12Data Types
2.1.13Casting
2.1.14Arrays
2.1.152D Arrays
2.1.16Lists
2.1.172D Lists
2.1.18Strings
2.1.19Syntax Errors
2.1.20Logic Errors
2.1.21Runtime Errors
2.1.22End of Topic Test - Programming
2.2Designing Code
3Hardware & Software
3.1Hardware
3.2Software
4Data
5The Internet
6Online Safety & Security
6.1Protecting Yourself Online
Jump to other topics
1Computational Thinking & Algorithms
1.1Computational Thinking
1.2Algorithms
1.2.1Algorithms
1.2.2Pseudocode
1.2.3Flow Diagrams
1.2.4Logical Reasoning & Debugging
1.2.5Reading Algorithms
1.2.6Correcting Algorithms
1.2.7Complete the Algorithm
1.2.8Search Algorithms
1.2.9Linear Search
1.2.10Binary Search
1.2.11Sort Algorithms
1.2.12Bubble Sort
1.2.13Insertion Sort
1.2.14End of Topic Test - Algorithms
2Programming
2.1Programming Fundamentals
2.1.1Variables & Constants
2.1.2Comments
2.1.3Input & Output
2.1.4Arithmetic Operators
2.1.5Relational Operators
2.1.6Boolean Operators
2.1.7Sequence
2.1.8Selection
2.1.9Iteration
2.1.10Subroutines
2.1.11Scope
2.1.12Data Types
2.1.13Casting
2.1.14Arrays
2.1.152D Arrays
2.1.16Lists
2.1.172D Lists
2.1.18Strings
2.1.19Syntax Errors
2.1.20Logic Errors
2.1.21Runtime Errors
2.1.22End of Topic Test - Programming
2.2Designing Code
3Hardware & Software
3.1Hardware
3.2Software
4Data
5The Internet
6Online Safety & Security
6.1Protecting Yourself Online
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