Microcontroller and Microprocessor are the brain and heart of the embedded system. Are you looking for a way to find out which one is the best one?
To understand the difference between the two, we need to understand the development of the processor and their positioning.
As the core accessory of a computer, the central processing unit (CPU) is mainly composed of a controller and an arithmetic unit to realize the interpretation of computer instructions and data processing in computer software.
With the iterative update of processor architecture design and the continuous improvement of integrated circuit technology, DSP, MCU, and MPU was born. MCU and MPU are actually two devices optimized to meet two different needs. The MCU mainly performs the management and control functions of hardware devices, and usually integrates a small-capacity memory inside a single chip in a monolithic way to realize the "monolithic cation" of the system. The MPU mainly executes complex and diverse large-scale programs and requires relatively powerful computing processing capabilities.
MCU is generally used in remote control, consumer electronics, and on various occasions with high real-time requirements. MPUs are used more in applications that require a large amount of computation, high-speed interconnection, or graphics interaction.
MCU vs MPU
What is Microcontroller?
A microcontroller is a single integrated circuit that integrates FLASH, RAM, and some peripherals, usually for a specific application and designed to perform certain tasks.
The microprocessor mainly completes "control" related tasks. MCUs generally do not require a large memory capacity. It has a single task type and only needs to complete some simple stimulus-response tasks without running a large operating system to support complex multitasking management.
Mainstream MCUs are mainly divided into 8-bit, 16-bit, and 32-bit. Early on, MCUs were built on a Harvard architecture that drove innovation through manufacturers such as Intel, Motorola, Microchip (PIC Microcontroller), and Atmel. ARM's 32-bit MCU has gradually replaced the popular 8/16-bit MCU in the past. At present, the leading manufacturers of MCUs are STMicrroelectronics (STM32), Microchip, NXP, and so on.
MCUs are programmable and operate by executing program instructions stored in non-volatile dual inline memory modules (NVDIMMs).
For example, a temperature display controller connects a temperature sensor and an LCD screen display to the MCU, and the MCU takes the sampled temperature value as an analog input and converts it to a numerical value, which is then displayed on the LED display through the correct command logic.
What is Microprocessor?
The Microprocessor is a programmable special integrated circuit. When used to process general-purpose data, it is a central processing unit, such as an Intel Pentium CPU. Dedicated to image data processing, it is Graphics Processing Unit, such as Nvidia Geforce 7X0 GPU. For audio data processing, it is called Audio Processing Unit, such as Creative emu 10k1 APU.
The MPU mainly performs processing functions and requires high data processing and computing power. Different from MCU, MPU is equivalent to a miniaturized central processing unit. It needs to run a larger operating system to realize complex task processing, so it requires a higher frequency. The MPU frequency of the early classic Arm9 system is 200MHz to 400MHz, and the high-end MPU used in mobile phones now reaches 3GHz.
Intel X86, TI AM335X, etc. all belong to MPU. MPU evolved to 32-bit processors very early, and now 64-bit is also more and more popular. Its most influential manufacturer is ARM.
In order to support the powerful computing power of the MPU, it is often necessary to integrate storage mechanisms and hardware such as high-performance storage controllers and storage management units.
The Boundary Between MCU and MPU is Getting Blurred
From the morphological point of view, the MCU often only needs to use the small memory integrated on the chip, while the MPU generally needs external memory to run because it needs to run large-scale programs that require complex processing capabilities.
However, with the continuous evolution of technology, the boundaries between today's MCU and MPU have gradually blurred. The main frequency of the MCU is constantly improving, and the peripherals are increasing. For example, the MCU with the main frequency of 1GHz and powerful computing power introduced by NXP. The advancement of 3D packaging and Chiplet technology, it has also promoted the realization of "monolithic integration" of large-capacity memory in the form of advanced packaging.
When performance and memory are no longer the bottlenecks of the MCU, it means that the MCU will move closer to the low-end MPU. Many ARM Cortec-M7-based MCUs offer over 100 Dhrystone MIPS, or over 2000 points in CoreMark. Many of these devices also have very large built-in memory or provide a fast interface to connect external memory.
It is not comprehensive enough to distinguish MCU and MPU from any point of view. Therefore, instead of distinguishing them, it is better to consider which device is more suitable for the realization of the target application from the usage scenario.