- Fastest memory / high speed
- It holds the data for immediate processing / temporary
- Less access time
- A group of flip flop is called register
- Data holding capacity is very less
Types of register
- MAR(Memory Address Register): It contains the address in memory of the word to be written from or read into the MBR.
- MBR(Memory Buffer Register): It contains of a word to be stored in memory or is used to received a word from memory.
- IR(Instruction Register): Contains the 8-bit op-code instruction being executed.
- IBR(Instruction Buffer Register): It is used to temporary hold the instruction from a word in memory.
- PC(program Counter): contains the address of the next instructions to be executed. It holds 16 bits data
- Accumulator: Stores the result of arithmetic and logic operations. It holds 8 bit data and accessible to the programmer.