What is a Microcontroller?
A microcontroller is an integrated circuit that is designed to control the input and output of an electronic device. The first microcontroller was developed back in 1971 by two engineers at Texas Instruments; Gary Boone and Michael Cochran. Boone and his colleagues noticed there was a high demand for an integrated circuit that came in a smaller, more condensed form. After many hours of blueprinting and experimentation, the first microcontroller was born and the rest is history!
How Microcontrollers Work
The microcontroller unit is essentially a mini-computer in a chip. It controls the functions of a device by interpreting data it obtains from peripherals. In case you are not familiar with peripherals, they assist with the input and output of information. An example of a peripheral would be a graphics card or image scanner.
Information that is obtained from the microcontroller is then added to its data storage, and the microprocessors embedded within apple the data to create actions. To illustrate how a microcontroller works, let’s look at a video game controller. The player hits a button to select an option in their game, and the microcontroller takes that input and produces the desired action--selecting the option. Think of it this way; any electronic device that is involved with controlling a system and carrying out subsequent actions most likely has an embedded microcontroller. We will get into more applications later.
The System
There are many three main components to the microcontroller, one of which was mentioned earlier: the processor, memory, and input/output peripherals.
PROCESSOR
Also known as the Central Processing Unit (CPU) the processor is at the heart of the microcontroller’s functionality. It processes and responds accordingly to input and output data, as well as performs data transfers.
2. MEMORY
Much like memory stored in a computer’s hard drive, a microcontroller’s memory stores data obtained from the processor and uses that data to produce actions. There are two types of memory to keep in mind: program memory and data memory. Program memory stores permanent data from the processor. The great thing about this type of memory is it can store information for long periods without a power source. Data memory is a bit more temporary. It stores data while actions are being made, but it can only do so when hooked up to a power source.
3. PERIPHERALS
Input and output peripherals receive and send information to the processor, and the processor then sends instructions based on that information to the output device. From there, the device carries out the desired action.
The Components
Nearly every microcontroller consists of five main components: the CPU, RAM, Digital Converters, Serial Bus Interface, and Input/Output ports. Each component is fairly complex, so we’ll try to break it down in as simple terms as possible.
The CPU - As you may already know, CPU stands for Central Processing Unit. It is the microcontroller’s headquarters, if you want to look at it that way, and it controls all information flowing in and out of the microcontroller. The CPU is made up of two main parts: the Arithmetic Logic Unit (ALU) and the Control Unit (CU). The ALU conducts all arithmetic (aka math) and logic operations, while the CU assists in executing the processor’s instructions.
RAM - You’ve probably heard the term RAM before if you work with computers. RAM, or Random Access Memory, stores data temporarily. The data stored can be accessed quickly, and the RAM allows the microcontroller to process lots of bits of information simultaneously.
Digital Converters - There are two types of converters in a microcontroller, and they are an Analog to Digital Converter (ADC) and a Digital to Analog Converter. (DAC). Both are pretty straightforward; the ADC converts analog signals to digital signals, and the DAC converts digital signals to analog signals. Both converters enable the processor to communicate with external components and devices.
Serial Bus Interface - The Serial Bus Interface connects Integrated Circuit Chips with traces on the Printed Circuit Board embedded within the microcontroller. The purpose of the Serial Bus Interface is to connect all the components. They are the veins of the entire system.
Input/Output Ports - Finally, there are the input and output ports. These are the microcontroller’s connections to external devices. Input ports receive data such as temperature and motion, and send that data to the CPU to interpret. The output port receives those input data signals, and then carries out an action based on the information obtained, such as turning a device off.
Uses
There are hundreds of applications for microcontrollers, and they range from consumer electronics to safety devices. Here’s a shortlist of the most common uses:
Computer keyboard
Computer monitor
Printer
Smartphone
Tablet
Microwave
Security system
Television
DVD player
Car dashboard
Car engine
All in all, microcontrollers are a fundamental and essential component in all electronics and without them, we wouldn’t have half the products we do today. If you are interested in prototyping at home with microcontrollers, we highly recommend picking up these boards from Arduino.
Arduino Uno
The Arduino Uno is by far the most popular board on the market, and is the best one for beginner prototypers. It’s robust, easy to use, and affordable at only $23!
Arduino Nano
The Arduino Nano is everything you could want in a microcontroller board, but in a smaller package. The best feature of the Nano is its breadboard-friendly configuration.