Introduction:

Nowadays, days of the technology age, the vast majority of people are familiar with computers, laptops, smart phones, add to that the software related to each mentioned item, so as result, people give special interest to the core of the previous modern devices, that core is the microprocessor.

So, almost every person is familiar with the term microprocessor, but from technical point of view, what is the microprocessor? And what is the term microcontroller that appeared in the title? And how are microcontrollers and microprocessors are related?

 What is the microprocessor (µP)?

The µP is an integrated circuit that is contained in a single chip, it performs the central processing and internal functions of a computer, the µP is the dominant controller in the computer, it governs and synchronizes all the task in the machine, the µP is a high speed chip, sometimes it is called CPU (Central Processing Unit), it can be classified based on many properties such as speed, internal structure, address buss number (which is an old classification).

When executing a task, the µP repeatedly goes through a three stages: fetching, decoding, executing, each contains many details to be discussed which is not the aim of this text, but generally speaking, the µP performs one task each instant.

Despite of the µP high performance, but it suffers from some drawbacks, it performs a single task each instant, also the µP can’t be used alone to control a device or a machine, it is dummy device, so it must be supplied with an external devices such as RAM’s, ROM’s, ADC’s and DAC’s to help it doing its job.

Talking about µP contains many deeper details, but they are Irrelevant to our text, but reader may construct a concept if referred to the address buss, fetching, decoding, executing, articles.

What is the microcontroller (µC)?

The µC is a single chip integrated circuit that is designed to function as an embedded system (contains a CPU, RAM, ROM, ADC’s, I/O ports and timers), the µC’s are intended for controlling user designed applications not computers, the µC also can synchronize its tasks, the applications that µC can control depends on its size, and as in the µP, µC can be classified based on many properties such as speed, internal structure, size/type of internal memory, Input/output number, sometimes the µC is called (computer in chip) because external components used in µP are embedded (build in) in the case of µC, so µC almost does not need an external components to make it work.

When executing a task, the µC repeatedly goes through the same three stages as the µP, but in a different manner, but generally speaking, the manner µC works is better, it performs two tasks each instant.

Despite that µC is smaller and slower than µP, but it can perform two tasks each instant, and it is easier to use as a hardware and software, it’s main feature is that no need for many external components to make it function.

 Then what is the relation between µC and µP?

The µC is basically a µP but in a smaller scale, in other words, µC can be considered as a small µP with special and different design and requirements, both µC and µP contains logic circuits inside, so they are logic IC’s, both are used for controlling things, they are programmable, despite the differences between them, but they are related in the things we mentioned.