The Central Processing Unit (CPU) performs the valid processing of data. The data it processes is obtained through the system bus from the main memory. Results from the CPU are then sent back to main memory through the system bus and also the CPU controls and co-ordinates the operation of the other major components.
The Three Main Components Are
The Main Memory
The Control Unit
The Arithmetic/Logical Unit (ALU)
Main Memory (Primary Memory)
Main Memory is also known as primary memory or internal memory is the working memory of the CPU with fast access and limited numbers of bytes being transferred.
The memory can hold program instructions, data values, and the intermediate results of calculations.
All the information on memory is encoded in fixed size cells called bytes. A byte can hold a small amount of information, such as a single character or a numeric value between 0 and 255. Is the immediate access memory and of a limited in capacity and temporary in nature. The standard base memory is 640K or KB. It may enhance up to 1MB, 2MB, 8MB, 16MB, 32MB, 64MB, and 128MB depending on the need of the user.
The main memory is constructed from integrated circuits and needs to have electrical power in order to maintain its information. When power is lost, the information is also lost.
Types Of Main Memory
ROM – Read Only Memory
RAM – Read Access Memory
PROM – Programmable Read Only Memory
EPROM – Erasable Programmable Read Only Memory
EEPROM – Electronic Erasable Programmable Read Only Memory
RAM – Is identical to core memory in function and is a read / write memory.
Data can be stored in the RAM by addressing one RAM cell. The data and instructions fed in via input device which are stored in the RAM so it may called as user’s memory. RAM instructions are temporary in nature and can be updated.
Continue: Central Processing Unit – Part 2