Computer architecture
Describes how a computer is designed and built to function, including how parts of the computer are designed, organised, and connected.
# von Neumann computer architecture
There may be many kinds of computer architecture, but a popular one (that is used in current studies) is the von Neumann computer architecture. The architecture describes a computer with the following components:
- a central processing unit with both an arithmetic logic unit and registers;
- control units that include an instruction register and program counter;
- memory to store data and instructions;
- external secondary storage; and
- input and output mechanisms.
Generally, the architecture also defines the use of buses (collections of wires used as a medium to transport data from one part of a computer to another). There are three buses that are used in this architecture:
- Data bus: A bidirectional (two-way) bus that is mainly used to transport data between the memory, I/O devices, and processor
- Address bus: A unidirectional (one-way) bus that is mainly used to transport address information usually from the processor to memory
- Control bus: A bidirectional (two-way) bus that is mainly used to transport control signals and clock pulses