Computers as we know them were first built in the 1940s and two of the early pioneers were Alan Turing and John von Neumann. The von Neumann architecture specifies the basic components of the computer and processor in which a shared memory and bus are used for both data and instructions.
The stored program concept:
A program must be resident in the main memory to be executed.
Machine code instructions are fetched, one after another, from main memory in sequence and are executed, one at a time, in the processor.
Virtually all computers today are built on this principle, and so the general structure as shown in the figure below is sometimes referred to as the von Neumann machine.
How data is stored in computer memory?
All data and instructions are stored in the Main Memory.
Data is stored in memory in binary code.
Central Processing Unit (CPU)
Central Processing Unit is a brain of computer.
Control Unit is the part of the processor that manages the execution of instructions.
ALU is the part of the processor that processes and manipulates data, carries out two types operation – arithmetic (+,-,*,/) and logic (AND, OR, NOT, etc).
Registers - the section of high speed memory within the CPU that stores data to be processed.
Describe the Von Neumann model of computer architecture. (5 marks)
The computer has a memory that can hold data and the program (1) (nowadays called RAM).
The control unit manages the process of moving the data (1) and program between memory and storage is called the "accumulator" in the von Neumann design. (1).
The ALU is the calculator in the model (1). It also operates relative calculations such as "less than".
The bus indicates the flow of data (1) between each component and is shown as arrows on the diagram.
Central Processing Unit is a brain of computer.