Harvard Architecture

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Harvard Architecture

Harvard Architecture

Disclaimer: I (Charlotte Turner) am in no way responsible for anything written here

It got worse after I copied and pasted

Von neumann: Most desktop computers

Harvard - used to solve the problem of a bottleneck data bus in the Von Neumann machine

Harvard: Other devices

Pros:

Faster data transfer through CPU.

Parallel access is available.

Instructions executed in one cycle.

Good for small embedded computers

The CPU can read instructions and perform data memory access at the same time

Cons:

Production of a computer with 2 buses is more expensive.

Free data memory cannot be used for instruction.

In Harvard architecture, the data bus and address bus are separate. That means a greater flow of data is possible through the central processing unit, and with that a greater speed of work. Separating a programme from data memory makes it further for instructions not to have to be 8-bit words. For example the Microchip PIC16F84 microcontroller uses 14 bits for instructions which allows for all instructions to be one word instructions. It is also typical for Harvard architecture to have fewer instructions than Von-Neumann's, and to have instructions usually executed in one cycle.