Register is a special- purpose memory. This memory is vital for moving data in and out of the main memory and to process the data. When CPU executes the instructions, there is a transfer of information between various units of the computer system. CPU uses these registers to handle the process of execution effectively and efficiently. They are a part of the central processing unit but can not be considered as a part of main memory. They can hold only one piece of data at a time. Registers receive the information, hold it temporarily and pass it on as directed by the control unit. The number of registers varies from computer to computer, each one designed to perform a specific function. Registers have a specific storage capacity normally 14 registers are present in a microcomputer. The most commonly used registers are:
Accumulator: stores the result of the last processing step of the ALU.
Instruction register: holds the instruction while it is being executed.
Address register: holds the location of the next piece of data.
Storage register: holds the information on its way to and from the main memory.
Program counter: holds the address of the next instruction to e executed.
Input/output register: communicates with the input/output devices.
The central processing unit contains a number of memory locations which are individually addressable and reserved for specific purpose. These memory locations are called registers. Some of theses registers are accessible to the programmer while some others are for the exclusive use of CPU. This latter set of registers is used for storage, interpretation and execution of instructions and the intermediate results. Total number of these registers varies among different computers. Widely used microprocessors have got eighteen 32-bit data registers which are used for storing instructions and operand of various sizes. One of these seven are 32-bit general purpose registers.
These registers are accessible to the programmer and are used for holding addresses or as index registers for indexed memory addressing. We describe below some important central processing registers. The first one is the program counter. This is 16-bit register. Its only function is to hold the memory address of the next instruction to be fetched, after executing the current instruction it is also called instructions address register, control register or sequence control register. The second one is instruction registers. It is 32-bit register. It is used to store the current instructions which are being executed. These registers are the part of the computer.
Registers are the group of flip flops. Flip flogs are the storage elements of storing one bit information. Register also have some combinational circuits that perform data processing tasks. Group of flip flops and gates form a registers. Simple registers consist of only flip flops. Registers are used to speed up the execution of computer programs. Different types of register are available in market. User visible registers, data registers, address registers, conditional registers, general purpose registers, floating point registers, accumulator, constant registers, vector registers, special purpose registers and control and status registers are different types of registers. User visible register are divided into to types data registers and address registers.
Data registers is basically used to store data. Accumulator register is special data register. Address registers are used to hold memory registers. Index register used to store the index of memory address. Condition registers are used to determine whether this instruction should execute or not. General purpose register hold the data and addresses. Floating point registers are the type of data register that store floating point numbers. Constant registers are used to store read only values. Special purpose register is used to store the status of the program. It consist of program counter, stack pointer and status registers.
Registers or Processor Registers are part of the computer architecture. It is a small storage space that is available on the CPU which can be used more quickly than any other storage capacity available on the computer. Most of the computer systems these days, have this rule of moving data from main memory to the register, then operating on them and moving them back to the main memory.
There are a number of types of registers in a computer each having their own specific purpose. Such as :
- User-Accessible Register: It is divided into data register and address resgisters. - Data Registers: They hold numeric values. An example is Accumulator. - Address Register: They hold addressed. - Special Purpose Registers: They have the program count and hold program state. - Control and Status register: It is used for getting information from RAM. - Vector Register: It is a register that has data for vector processing.
There are different numbers of registers in different CPUs. For instance, in a 8086CPU, there are 14 types of register, including segment registers, general purpose registers, index registers and code registers.
Registers are temporarily storage devices made of up of group of flip-flops. While processing the different type of jobs are made through these registers data is transfered from main memory to any out put devices like computer monitor via registers. There are different types of registers like General purpose register, program counter registers etc
Most of the registers in the machine have two-way copy capability; that is, you can copy to them from another register, and you can copy from them to another register. Name the register that works in this manner in relation to the read and write operation. Explain clearly why this is so.
There are a number of types of registers in a computer each having their own specific purpose. Such as :
- User-Accessible Register: It is divided into data register and address registers. - Data Registers: They hold numeric values. An example is Accumulator. - Address Register: They hold addressed. - Special Purpose Registers: They have the program count and hold program state. - Control and Status register: It is used for getting information from RAM. - Vector Register: It is a register that has data for vector processing.
CPU register is a memory address for a specific amount of data. And instructions in CPU are executed by using these memory addresses. And they are used to locate some memory saved in Central Processing Unit.
