A multiprocessor system on a chip (, ' or ) is a

system on a chip A system on a chip or system-on-chip (SoC ; pl. ''SoCs'' ) is an integrated circuit that integrates most or all components of a computer or other electronic system. These components almost always include a central processing unit (CPU), memory ...

(SoC) which includes multiple microprocessors. As such, it is a

multi-core A multi-core processor is a microprocessor on a single integrated circuit with two or more separate processing units, called cores, each of which reads and executes program instructions. The instructions are ordinary CPU instructions (such a ...

system on a chip. MPSoCs are usually targeted for embedded applications. It is used by platforms that contain multiple, usually

heterogeneous Homogeneity and heterogeneity are concepts often used in the sciences and statistics relating to the uniformity of a substance or organism. A material or image that is homogeneous is uniform in composition or character (i.e. color, shape, siz ...

, processing elements with specific functionalities reflecting the need of the expected application domain, a memory hierarchy and I/O components. All these components are linked to each other by an on-chip interconnect, such as

buses A bus (contracted from omnibus, with variants multibus, motorbus, autobus, etc.) is a road vehicle that carries significantly more passengers than an average car or van. It is most commonly used in public transport, but is also in use for cha ...

and Networks on chip (NoCs). These architectures meet the performance needs of multimedia applications, telecommunication architectures, network security and other application domains while limiting the power consumption through the use of specialised processing elements and architecture.

Structure

A multiprocessor system on a chip must by definition have multiple processor cores. MPSoCs often contain multiple logically distinct

processor Processor may refer to: Computing Hardware * Processor (computing) **Central processing unit (CPU), the hardware within a computer that executes a program *** Microprocessor, a central processing unit contained on a single integrated circuit (I ...

modules as well. Additionally, MPSoCs typically contain: * Memory blocks, often using

scratchpad RAM Scratchpad memory (SPM), also known as scratchpad, scratchpad RAM or local store in computer terminology, is a high-speed internal memory used for temporary storage of calculations, data, and other work in progress. In reference to a microprocess ...

and

direct memory access Direct memory access (DMA) is a feature of computer systems and allows certain hardware subsystems to access main system memory independently of the central processing unit (CPU). Without DMA, when the CPU is using programmed input/output, it is ...

* timing sources to generate clock signals to control execution of SoC functions **

crystal oscillators A crystal oscillator is an electronic oscillator circuit that uses a piezoelectric crystal as a frequency-selective element. The oscillator frequency is often used to keep track of time, as in quartz wristwatches, to provide a stable clock s ...

and

phase-locked loops A phase-locked loop or phase lock loop (PLL) is a control system that generates an output signal whose phase is related to the phase of an input signal. There are several different types; the simplest is an electronic circuit consisting of a ...

are popular clock generators. * peripherals including counters and

power-on reset A power-on reset (PoR, POR) generator is a microcontroller or microprocessor peripheral that generates a reset signal when power is applied to the device. It ensures that the device starts operating in a known state. PoR generator In VLSI d ...

generators * external

interfaces Interface or interfacing may refer to: Academic journals * ''Interface'' (journal), by the Electrochemical Society * ''Interface, Journal of Applied Linguistics'', now merged with ''ITL International Journal of Applied Linguistics'' * '' Inte ...

, typically for

communication protocols A communication protocol is a system of rules that allows two or more entities of a communications system to transmit information via any kind of variation of a physical quantity. The protocol defines the rules, syntax, semantics and synchroniza ...

** These are often based upon industry standards such as

USB Universal Serial Bus (USB) is an industry standard that establishes specifications for cables, connectors and protocols for connection, communication and power supply ( interfacing) between computers, peripherals and other computers. A broa ...

FireWire IEEE 1394 is an interface standard for a serial bus for high-speed communications and isochronous real-time data transfer. It was developed in the late 1980s and early 1990s by Apple in cooperation with a number of companies, primarily Sony a ...

Ethernet Ethernet () is a family of wired computer networking technologies commonly used in local area networks (LAN), metropolitan area networks (MAN) and wide area networks (WAN). It was commercially introduced in 1980 and first standardized in ...

USART A universal synchronous and asynchronous receiver-transmitter (USART, programmable communications interface or PCI) is a type of a serial interface device that can be programmed to communicate asynchronously or synchronously. See universal asynchron ...

SPI SPI may refer to: Organizations * Indian Protection Service (''Serviço de Proteção ao Índio''), Brazil * Shotmed Paper Industries, an Egyptian paper manufacturers * Simulations Publications, Inc., a former US board game publisher * Sony P ...

HDMI High-Definition Multimedia Interface (HDMI) is a proprietary audio/video interface for transmitting uncompressed video data and compressed or uncompressed digital audio data from an HDMI-compliant source device, such as a display controll ...

I²C I2C (Inter-Integrated Circuit, ), alternatively known as I2C or IIC, is a synchronous, multi-controller/multi-target (master/slave), packet switched, single-ended, serial communication bus invented in 1982 by Philips Semiconductors. It is w ...

, etc. ** each interface is typically to one given core or logical unit on the MPSoC *a

network on a chip A network on a chip or network-on-chip (NoC or )This article uses the convention that "NoC" is pronounced . Therefore, it uses the convention "a" for the indefinite article corresponding to NoC ("a NoC"). Other sources may pronounce it as a ...

(NoC) to communicate and share data between the processors and functional units of the MPSoC

Applications

MPSoCs are used when

microcontrollers A microcontroller (MCU for ''microcontroller unit'', often also MC, UC, or μC) is a small computer on a single VLSI integrated circuit (IC) chip. A microcontroller contains one or more CPUs ( processor cores) along with memory and programmab ...

or systems-on-chip must have

multiprocessing Multiprocessing is the use of two or more central processing units (CPUs) within a single computer system. The term also refers to the ability of a system to support more than one processor or the ability to allocate tasks between them. There ar ...

capabilities. This can include

smartphone A smartphone is a portable computer device that combines mobile telephone and computing functions into one unit. They are distinguished from feature phones by their stronger hardware capabilities and extensive mobile operating systems, whic ...

devices,

embedded systems An embedded system is a computer system—a combination of a computer processor, computer memory, and input/output peripheral devices—that has a dedicated function within a larger mechanical or electronic system. It is ''embedded'' ...

digital signal processors A digital signal processor (DSP) is a specialized microprocessor chip, with its architecture optimized for the operational needs of digital signal processing. DSPs are fabricated on MOS integrated circuit chips. They are widely used in audio sig ...

and other various applications.

Examples

This section is a short list of multiprocessor systems-on-chip. *

Cell processor Cell is a multi-core microprocessor microarchitecture that combines a general-purpose PowerPC core of modest performance with streamlined coprocessing elements which greatly accelerate multimedia and vector processing applications, as well as ...

Adapteva Zero ASIC Corporation, formerly Adapteva, Inc., is a fabless semiconductor company focusing on low power many core microprocessor design. The company was the second company to announce a design with 1,000 specialized processing cores on a single ...

's Epiphany architecture *

Xilinx Xilinx, Inc. ( ) was an American technology and semiconductor company that primarily supplied programmable logic devices. The company was known for inventing the first commercially viable field-programmable gate array (FPGA) and creating the fi ...

Zynq UltraScale

Design considerations

Benchmarks

MPSoC

research and development Research and development (R&D or R+D), known in Europe as research and technological development (RTD), is the set of innovative activities undertaken by corporations or governments in developing new services or products, and improving existi ...

often compares many options. Benchmarks, such as COSMIC, are developed to help such evaluations.

References

External links

MPSoC - Annual Conference on MPSoC

Annual Symposium
{{compu-hardware-stub Microprocessors System on a chip