System bus model
![]() | It has been suggested that this article be merged into Von Neumann architecture. (Discuss) Proposed since October 2010. |
![]() | It has been suggested that this article be merged into System bus. (Discuss) Proposed since May 2011. |

The system bus model is a streamlined version of the von Neumann model of computer architecture.[1] Its main feature is that it interconnects the processor, memory, and I/O subsystems by a single bus, divided in 3 components: data bus, address bus, control bus.[2] Contemporary computer systems use several buses for cost-performance tradeoff reasons.[3]
Communications
The system bus models divides the computer into three individual subunits which are the CPU, memory and input/output. The system bus model deviates from the von Neumann model by combining the arithmetic logic unit (ALU) and the central processing unit (CPU) into a single unit.[2]
The system bus is composed of the data bus, address bus, control bus, power bus and sometimes an I/O bus.[2]
The data bus is used for transfer of data between subunits while the address bus is used to transmit location information between units such as where the data is going or coming from.[2]
The control bus is used to provide information as to how data is being sent.[2]
The power bus is often not graphically depicted on models but is understood to exist. Furthermore, some more complex architectures may also incorporate a separate I/O bus for transfer of data between input/output devices.[2]
References
- ^ Linda Null; Julia Lobur (2006). The essentials of computer organization and architecture (2 ed.). Jones & Bartlett Learning. ISBN 9780763737696.
- ^ a b c d e f Murdocca, Miles J. (2000). Principles of Computer Architecture. Prentice-Hall. p. 5. ISBN 0-201-43664-7.
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suggested) (help) - ^ William Stallings (2009). Computer organization and architecture: designing for performance (8th ed.). Prentice Hall. pp. 66 & 87-89. ISBN 9780136073734.