Registers are temporary memory unit.
Registers are used for holding various types of informations like data, intermediate results, instructions and addresses.
Features of Registers
Registers are high speed memory used for special purpose.
Registers are used to hold the informations on which CPU is currently working on. Hence Registers can be thought of as CPU's working memory.
Registers work under the direction of control unit.
Under control unit's instruction Registers accept, hold and transfer data while performing arithmetic or logical operations at very high speed.
Computers contain registers within CPU for faster operations
The number of registers in a computer differs from processor to processor.
Following types of Registers are available:
Accumulator: Accumulator is one of the most frequently used registers by CPU. Number of accumulators in CPU varies from computer to computer.
General-purpose registers: General-purpose registers are used for storing data and intermediate results during program execution.
Special-purpose registers: There are numerous special-purpose registers in CPU for various purposes. Some of the commonly used special-purpose registers are Program Counter, Instruction Registers, Stack Pointer, Memory Address Register, etc. They are used for holding address of the next instruction to be executed. It can hold operation code that is currently getting executed. It holds the starting address of the memory stack and many more such tasks are performed by them.
Register Transfer Language (RTL) is the symbolic notation that is commonly used to represent the micro-operation transfer between two registers.