Computer Registers

Computer registers are very fast computer memory type, used to store data/instruction.

A computer Register is a group of flip-flops with each flip-flop capable of storing one bit of information. An n-bit register has a group of n flip-flops and is capable of storing binary information of n-bits.

A register consists of a group of flip-flops and gates. The flip-flops hold the binary information and gates control when and how new information is transferred into a register. Various types of registers are available commercially. The simplest register is one that consists of only flip-flops with no external gates.

Following are some commonly used registers:

1. Accumulator: This is the most common register, used to store data taken out from the memory.
2. General Purpose Registers: This is used to store data intermediate results during program execution. It can be accessed via assembly programming.
3. Special Purpose Registers: Users do not access these registers. These registers are for the Computer system,

• MAR: Memory Address Register are those registers that holds the address for memory unit.
• MBR: Memory Buffer Register stores instruction and data received from the memory and sent from the memory.
• PC: Program Counterpoints to the next instruction to be executed.
• IR: Instruction Register holds the instruction to be executed.