How CPUs Work?

The use and importance of computer, whether in home or professional use, cannot be understated. This machine has completely changed the world and is definitely here to stay. It has completely changed the people’s lives in whatever they do. From daily tasks to business activities, everything has changed all because of computers. Thus, it is necessary to know how the computer can really do its tasks. This essay discusses how the computer’s brain – the Central Processing Unit (CPU) works.
The CPU or the Central Processing Unit is considered as the brain of the computer (InetDaemon 2009). Without the CPU, the computer would not be capable of doing any of the tasks it is capable of doing. On the whole, the CPU is a chip responsible for handling the transfer and processing of data. With every upgrade of the CPU, it becomes more powerful and faster. Reliability and speed is usually the name of the game when CPU chips in new computers are being compared. For some people, the CPU brand is major consideration. The more powerful and the faster the CPU is, the more it will sell.
The CPU is found in the center of the motherboard. Because it carries out the largest share of works in the computer, pieces of data pass through it continuously. These pieces of data are from the Random Access Memory (RAM) and units such as drives, keyboards, etc. After processing, the pieces of data are transmitted back to Random Access Memory (RAM and the units (Torres 2005). The CPU continuously receives orders and commands to be executed. Each instruction or command is an order for data processing. The function itself consists usually of data transport and calculations.

The Data Types the CPU Handles
The CPU handles two data types at a certain time (Young 2002). One has to be processed while the other serves as the program coded connected to the given data. The programming code is the list of instructions pertaining to how the data is handled and processed using a language the CPU can read and interpret. This code also contains the system bus route for the data. Because the other components of the computer are not able to understand this programming code, it is the job of the CPU to read and interpret the instructions for those components. The CPU then continuously handles both types of data until they are no longer needed. This is when the program has been stopped or closed or when the user is no longer accessing the hardware.
The CPU Components
To fully understand how the CPU works, it is important to identify the components that make up the CPU (CPU 2009). These are the Control Unit and the Arithmetic/Logic Unit. The CPU’s control unit contains a circuitry that utilizes electrical signals to instruct the whole computer system to carry out and execute the stored instructions of the program. It is important to note that the control unit is not capable of executing program instructions. It just directs the other components of the computer system to do so. With this regard, the control unit is required to establish communication with the memory and the arithmetic/logic unit.
The Arithmetic/Logic Unit, on the other hand, contains an electronic circuitry that is responsible for the execution of all logical and arithmetic operations. This component can carry out four different kinds of mathematical calculations or arithmetic operations. These are addition, subtraction, multiplication, and division. The Arithmetic/Logic Unit also carries out logical operations which are usually a comparison. It is capable of comparing letters, numbers, and special characters.
Based on the output of the comparison, the computer system can take actions. This is an important capability. It is through the comparison that the computer system can tell, for example, whether some seats on an airplane are still unfilled, whether credit-card customers have already exceeded or maxed out their credit limits, or whether a candidate for Presidency has earned more votes than other candidates. The logical operations can be tested for three conditions (How Computers Work: The CPU and the Memory 2003):
·         Equal-to Condition – In this condition, the computer system compares values to check if the values are equal.
·         Less-than Condition – In this condition, the computer system compares values to check if one is less than the other.
·         Greater-than Condition – In this condition the computer system compares values to check if one is greater than the other.
The CPU’s Instruction-Execution Cycle
There are many types of computers capable of executing instructions and commands as fast as one-millionth of a second. There are also supercomputers capable of executing instructions as fast as one-billionth of a second. For both types of computers, the CPU performs the following steps to execute a certain instruction (King 1999):