What is a Central Processing Unit (CPU)? Definition, Function and More

It is an electronic circuit on chips that performs the instruction of a specific computer software program performed by it. CPU is a very complex system of microprocessors that are found in desktop and laptop computers. A CPU can do various input/output (I/O) operation depending upon the instructions written on the chip. A CPU has different parts and functions that will be discussed further in the following.

The CPU performs different operations like instruction scheduling, execution control, and data storage. Instruction scheduling allows a programmer to give instructions to a CPU and the CPU executes the instruction given on the chip. Executing a particular instruction will allocate an address on the CPU’s memory to execute the instructions that has been stored in the form of an instruction pointer location. Instruction pointer location is found on the upper side of a CPU chip. If any instruction pointer is dereferenced by the CPU, it will result in an invalid operation.

Data storage is another task that is performed by a CPU. It is a system where all instructions, programs, signals, and other resources are stored. Computer software will load instructions or programs into the central processing unit (CPU) of the machine through bus connectors (ATA, PCI, AGP). The CPU will then access a host processing device to retrieve and execute instructions stored in the central processing unit.

An instruction pointer is also referred to as an instruction port. It is a transfer register that gets loaded with a specific instruction to execute. An instruction pointer will point to an instruction resource on the chip where a program will be loaded into the central processing unit. The main part of the CPU that handles instructions is called the microcontroller.

Programmable logic gates are the one that carries out instructions inside the CPU. Every gate has one input and one output. They are programmed using a Programming Unit or ROM. The one instruction that is carried out by a microcontroller is called a program word.

What is a CPU? As the name suggests it is the one who controls the execution of a program. A programmer writes the programs and the microprocessor interpret it into the right form. In the above case, the microprocessor is programmed to carry out instruction word that will carry out a particular instruction. There are also some microprocessors that can carry out more than one instruction at a time. This is known as a multiprogrammable processor or a monolithic computer.