Microprocessor

What is a microprocessor?

A microprocessor is a microchip that executes the tasks in a computer system. It’s the sole unit that performs every instruction that passes through it. A microprocessor is commonly referred to as the central processing unit (CPU), a logic chip, or just a "processor." They can be designed using a computer with printed circuit board (PCB) design software.

Microprocessors are critical computer components designed to execute simple and complex tasks. They comprise integrated circuits that hold multiple transistors.

A microprocessor’s power depends upon the number of instructions it can read and run within a specific period. Advancements in technology allowed computer engineers to develop microcomputers, small but powerful computers that perform business, industrial, and scientific jobs.

These days, microprocessors are used in laptops, home computers, industrial automation, and even mobile phones. Two examples of microprocessors are the Intel 4004 chip, one of the first processors, and the AMD Ryzen 5, a modern-day 64-bit microprocessor. 

Types of microprocessors

Based on their capability to run instruction sets, the three most common types of microprocessors are CISC, RISC, and EPIC.

CISC

CISC, or complex instruction set computer, can perform multiple sets of instructions at one time. It makes a single instruction perform the loading, evaluation, and storing operations. This approach reduces the number of instructions executed per program, but a single instruction performs many functions. Some examples of the CISC microprocessor chip are the Intel 486, Intel Pentium 2, and the Intel Pentium Pro.

RISC

RISC stands for reduced instruction set computer. Its purpose is to execute instructions very quickly. RISC’s core idea is to simplify the hardware by using an instruction set with only a few steps for loading, evaluating, and storing operations. Examples of RISC include DEC Alpha and IBM.

EPIC

EPIC, or explicitly parallel instruction computing, uses compilers and lets instructions run parallel. It encodes instructions in 128-bit loads. EPIC uses instruction-level parallelism (ILP) techniques such as speculation and predication. IA-64 is an example of an EPIC microprocessor.

How does a microprocessor work?

Microprocessors are manufactured using metal oxide semiconductor technology; they consume low power. Regardless of their power, size, or complexity, every microprocessor follows this basic sequence of actions: fetch, decode, and execute.

More simply, the instructions that must pass through the microprocessor are stored in sequence. It then “fetches” these instructions from memory, “decodes” them, and “executes” the instructions.

These instructions are first processed through a microprocessor’s arithmetic logical unit (ALU), which performs arithmetical and logical operations. Then the instructions go through the processor’s control unit and a register array. The latter sifts through data through multiple registers that act as quick access memory. The control unit manages the flow of this data.

Basic terms related to a microprocessor

Common terms related to a microprocessor are frequently discussed, such as:

• Bus refers to a set of conductors that pass data or take care of the control information. Microprocessors contain three buses: the address bus, the control bus, and the data bus.
• The instruction set is the number of commands a microprocessor can understand simultaneously. It bridges the gap between the hardware and the software.
• Cache is the component that stores the frequently processed instructions for quickness. It increases the speed of a processor since it allows it to access data quickly.
• Word length is the number of bits inside the microprocessor’s data bus. For example, if the word length of a processor is 16-bits, it can process 16-bits at a time, with 16-bit registers and a 16-bit data bus.
• Data types make up microprocessors. Different data types include American Standard Code for Information Interchange (ASCII), binary-coded decimal (BCD), and signed and unsigned numbers.
• Clock speed is the rate at which a microprocessor runs instructions. The measurement rate for all microprocessors is Hertz, and, depending on the speed, it can be expressed in short as “Hz.” For example, if a microprocessor runs at eight gigahertz, it can be expressed as 8 GHz. On the other hand, megahertz is expressed as “MHz.”

Benefits of a microprocessor

From small to large supercomputers, microprocessors are highly beneficial in many ways for use on various systems. 

• Size: Microprocessors were initially large and very impractical to use. The size has been highly reduced due to advancements in large-scale and ultra-large-scale integration technologies. The smaller the processor, the smaller the computer system. This makes it easier for original equipment manufacturers (OEMs) to fit more useful components into a computer system while also making it smaller.
• Speed: Microprocessors are known for high speed. High speed was only possible for personal computers or supercomputers, but because of technological advancements, portable devices such as smartphones today house ultra-fast processors. These processors can execute even a trillion instructions per second.
• Cost: The presence of integrated circuits and improvements in semiconductor manufacturing makes microprocessors available at low prices. This means that the overall cost of a computer system or a smartphone is greatly reduced.
• Accuracy: Microprocessors execute instructions at high levels of accuracy and efficiency.
• Power consumption: Good microprocessors consume low power while effectively executing instructions. This also means that they generate less heat.
• Built-in GUI: Modern microprocessors come with graphical user interfaces (GUI) built into the system. This means that there’s no need for a separate GUI, and in turn, this reduces the overall size of the device.
• Universal nature: Microprocessors’ many applications make them versatile, allowing different systems such as computers and smartphones to use them.

Microcontroller vs. microprocessor

On the surface, it seems like microprocessors and microcontrollers have much in common. Both single-chip integrated circuits have boosted computer technology and are found in many electronic devices worldwide.

At the core, however, they differ.

Microcontrollers are less expensive than microprocessors. The latter is typically used with more expensive devices that use external peripherals.

Microprocessors are meant to perform more complex functions, while a microcontroller usually performs only a dedicated function. This is one of the reasons why processors require a reliable external memory source to support complex tasks. Microcontrollers require less memory, less computing power, and are less complex than microprocessors.