Computer System
37
Learning Activity: The Von Neumann Architecture
Introduction
Over the years computer architecture has undergone incredible changes.
One thing that
has been preserved in the influx of changes over the year is the Von Neumann concept of
computer design. The v
on Neumann architecture
, also known as the von
Neumann
model
and
Princeton architecture
, is the first model to represent
the stored-program
concept that has fundamentally changed computing[1,2,3]. In the 1940s, a mathematician
called John Von Neumann described the basic arrangement (or architecture) of a computer
system. Most computers in use are designed based on the concept described by him although
there are other types of architecture.
The following are characteristics of a Von Neumann-based computer:
√ It uses a single processor.
√ It uses one memory for both instructions and data.
√ It cannot distinguish between data and instructions
in a memory location
√ It distinguishes between data and instructions only because of the location of a
particular bit pattern in RAM.
√ Executes programs by doing one instruction after the next in a serial manner
using a fetch-decode-execute cycle.
Components of the
Von Neumann Architecture
Figure 1- The Von Neumann Architecture (Source: Computer
Architecture and Organization by M. Murdocca & V. Heuring
Fig 1-14 page 10)
The above figure, Figure 1, depicts the
essential features of the
Von Neumann or stored-program architecture
