Dive into the world of embedded systems as we explore the distinctions between a microprocessor and a microcontroller. While both are the brains behind electronic devices, a microprocessor is the computational powerhouse driving general-purpose computers, whereas a microcontroller combines processing power with input/output peripherals, making it a self-contained system ideal for dedicated tasks.
Both microprocessors and microcontrollers are designed for real-time computing applications, and indeed they share many similar features. However, there are also very significant differences between the two in both conceptual and application levels.
What Is a Microprocessor?
In a nutshell, a microprocessor is an integrated circuit (IC) that is responsible for performing the necessary tasks and instructions of computer processing. All computers must have at least one microprocessor, that acts as the central unit that manages and executes all the logical tasks and instructions.
A microprocessor’s task is to execute computational and logical operations such as addition, subtraction, multiplication, inter-processes, device communications, input/output management, and so on. We can most certainly say that a microprocessor is the most important element of any computer. Without it, the computer simply can’t do its function.
Key Takeaway: a microprocessor is something small (micro) that processes data, instructions, and tasks (processor)
What Is a Microcontroller?
A microcontroller is a compact circuit that is designed to control or govern specific operations in an embedded system — a combination of hardware and software that is designed for specific functions, mainly as a part of a larger system.
A microcontroller typically consists of a microprocessor, i/o (input/output) devices, and memory on a single chip. We can say that a microcontroller is a computer on its own that is only able to do specific tasks (most often, only one specific task).
Microcontrollers are typically embedded inside another device, so it can control specific actions of the device. This is why a microcontroller is often called “embedded controller”. They are ideally suited for a dedicated low power application.
Key Differences: Microprocessor vs. Microcontroller
Memory Module and Data Storage
While microprocessors and microcontrollers differ in their architectures, the key difference lies in data storage. Microprocessors, relying on external memory, operate with a more extensive storage setup.
Microcontrollers, on the other hand, store program memory and data memory on the same chip, enhancing efficiency in embedded systems applications.
Clock Speed and Robust Computational Capacity
Microprocessors boast higher clock speeds, excelling in executing basic functions reliably and handling complex operating systems. Microcontrollers, operating at lower clock speeds, are champions in low power consumption scenarios, showcasing their robust computational capacity for specific applications.
Addressing the Buzzwords: Microprocessor vs. Microcontroller
Harvard Architecture and Address Bus
Microcontrollers often adopt the Harvard architecture, integrating an address bus for efficient data handling in embedded systems applications. This architecture enhances the processing capabilities of electronic systems in various modern electronic equipment.
Control Bus and External Operation
Microprocessors leverage control buses for external operation, managing the flow of data between internal registers and external components. This control mechanism makes them versatile in controlling a wide array of electronic systems, from desktop computers to different modern electronic equipment.
Decoding the Microprocessor Magic for Personal Computers
Processing Power and Versatile Computing Operations
At the core of personal computers lies the microprocessor, a robust central processing unit (CPU) that executes complex operating systems with versatile computing operations. These powerhouses, connected externally to various components, exemplify the epitome of computing power.
External Components and Total Power Consumption
Microprocessors, with their reliance on external components like data buses and external memory, offer unparalleled processing power. However, their total power consumption is something to consider, especially in desktop computers that demand robust computational capacity.
Unveiling Microcontroller Marvels in Embedded Systems
Compact Systems and Single-Chip Wonders
Embedded systems, found in electronic devices like washing machines, are governed by microcontrollers—a dedicated controlling unit within a single integrated circuit. Their internal controlling bus ensures efficient data flow within the same chip, making them perfect for compact systems.
Power Saving Mode and Dedicated Low Power Applications
Microcontrollers shine in power-saving mode, making them the go-to solution for dedicated low-power applications. Imagine controlling electronic devices with precision using just a small battery, thanks to the power-saving features embedded in microcontrollers.
Applications of a Microprocessor and Microcontroller
Microprocessors are the brains behind almost every electronic device we use today. Here is a breakdown of important microprocessor applications in various categories:
- In Personal Computers
- This includes PCs, laptops, tablets, smart phones and single-board computers (SBCs) to supercomputers.
- Other examples include gaming consoles, Smart TVs, digital cameras, printers, wearable devices and more.
- In Household Appliances
- Smart appliances and devices like a smart thermostat, smart doorbell, and smart security camera all employ sensors that are controlled by at least one microprocessor.
- Premium refrigerators, washing machines, coffee makers, and other similar appliances also contain a microprocessor.
- Transportation Industry
- Modern vehicles and public transportation use a microprocessor technology, for example, to access GPS systems, regulate its function, and so on.
- Health Industry
- Various medical devices are controlled by microprocessors to perform various purposes like collecting information from biosensors, analyzing health information from patients, and storing data.
Various devices and appliances rely on microcontrollers to perform specific operations, such as:
- Consumer appliances: Any automatic home appliances like microwave, washing machine, etc., also in children’s toys and cameras.
- Medical instruments: ECG, Accu-check, etc.
- Measurement instruments: multimeter, current tester, oscilloscopes, etc.
- Communication devices: smartphones, answering machines, telephone, fax, etc.
- Automotive and transportation: speedometer, ABS system, etc.
- Other equipment: MP3 player, printer, PDAs, etc.
Is the Raspberry Pi a Microcontroller?
It’s a common misconception to call the popular Raspberry Pi a microcontroller (and in some cases, some people might mistake it as a microprocessor). However, technically the Raspberry Pi is NOT a microcontroller, but rather it’s more accurate to call it a single-board computer or small board computer (SBC).
What Is an SBC?
In a layman’s term, a single board computer is a complete computer that is built on just one circuit board (often referred to as a single chip computer). It is a completely self-contained or embedded computer that is designed differently from standard general-purpose computers and can integrate more than one microprocessor, memory units, and input/output (I/O) peripherals.
An SBC is significantly different from a microcontroller mainly due to how an SBC is able to execute more than one or two specific operations and act more like a general-purpose computer. An SBC, however, can also perform as a microcontroller to control or govern specific functions when needed.
Below, we will discuss some of the popular SBCs available in the market today, their unique advantages and disadvantages, and key facts you might want to know.
The Raspberry Pi is arguably one of the most popular single-board computers available today, mainly due to its versatility, fairly complete set of features, and surprisingly powerful capabilities.
Also, the Raspberry Pi is among the easiest to use compared to other SBCs and has a fairly shallow learning curve. This is also due to Raspberry Pi’s huge community with hundreds of projects available, from simple ones like smart mirrors, to very complex ones like tablets and even functional robots.
- Broadcom BCM2712 2.4GHz quad-core 64-bit Arm Cortex-A76 CPU, with cryptography extensions, 512KB per-core L2 caches, and a 2MB shared L3 cache
- VideoCore VII GPU, supporting OpenGL ES 3.1, Vulkan 1.2
- Dual 4Kp60 HDMI display output with HDR support
- 4Kp60 HEVC decoder
- LPDDR4X-4267 SDRAM
- Dual-band 802.11ac Wi-Fi
- Bluetooth 5.0 / Bluetooth Low Energy (BLE)
- microSD card slot, with support for high-speed SDR104 mode
- 2x USB 3.0 ports, supporting simultaneous 5Gbps operation
- 2x USB 2.0 ports
- Gigabit Ethernet, with PoE+ support (requires separate PoE+ HAT)
- 2× 4-lane MIPI camera/display transceivers
- PCIe 2.0 x1 interface for fast peripherals (requires separate M.2 HAT or other adapter)
- 5V/5A DC power via USB-C, with Power Delivery support
- Real-time clock (RTC), powered by an external battery
If you want to learn more about how to use Raspberry Pi 4 in your project, we’d recommend Exploring Raspberry Pi: Interfacing to the Real World by Derek Molloy as your starting point.
Is the Beagleboard a Microprocessor and Microcontroller?
The BeagleBone Black is admittedly a relatively new SBC among its competitors and is originally developed as a low-cost, high I/O count SBC. Because of the sheer number of I/O points and raw power of this board, I simply love it!
- AM335x 1GHz ARM® Cortex-A8 processor
- 512MB DDR3 RAM
- 4GB 8-bit eMMC onboard flash storage
- 3D graphics accelerator
- NEON floating-point accelerator
- 2x PRU 32-bit microcontrollers
- USB client for power & communications
- USB host, Ethernet, HDMI connectivity
- 2x 46 pin headers for expandability
We recommend Exploring BeagleBone: Tools and Techniques, again written by Derek Molloy, if you want to learn more about BeagleBone SBCs — and especially BeagleBone Black.
Is Arduino a Microcontroller or Microprocessor?
Arduino and Raspberry Pi are often confused with each other for several reasons. Both of them are two of the most popular SBCs available today, they both began in as affordable budget hardware and STEM education, and they performed very similarly to each other.
However, they are actually very different from each other at their architecture level.
Arduino is based on microcontrollers, while a Raspberry Pi is actually a microprocessor integrated with on-board RAM and other peripherals. The Arduino is arguably easier to use than Raspberry Pi in building electronic prototypes, but the Pi is more versatile and can be used as a full desktop computer.
- 5V operating voltage
- 7-12 V recommended input voltage, 6-20 V lower and upper limits
- 14 digital I/O pins
- 6 PWM I/O pins
- 6 analog input pins
- 20 mA DC current per I/O Pin
- 50 mA DC current for 3.3V pin
- 32 KB Flash memory, 2KB SRAM, 1KB EEPROM
- 16 MHz Clock Speed
If you want to learn further about using Arduino in building your electronic projects, I’d recommend Exploring Arduino: Tools and Techniques for Engineering Wizardry, because of Jeremy Blum’s engineering first approach.
Making Sense of Microprocessors and Microcontrollers
Understanding the key differences between microprocessors and microcontrollers is crucial for navigating the tech terrain. Whether you’re working on personal computers or embedded systems applications like washing machines, the choice between these components shapes the efficiency and functionality of the entire system.
So, as you explore the world of processor cores, digital signals, and binary data, remember the power-saving features, processing power, and the intricate dance between internal and external components. Happy navigating the tech terrain!