RISC( Reduced instruction set computer ) A microprocessor that executes fewer types of computer instructions , come of 80 Chronological MIPS host ( Namely RISC machine ),RISC Microprocessors used in the machine are collectively referred to as microprocessors RISC processor .


thus , It can perform operations faster ( Executing millions more instructions per second , Namely MIPS).


Because the computer needs additional transistors and circuit elements to execute each instruction type , The larger the computer instruction set, the more complex the microprocessor will be , The operation will also be slower .


Performance characteristics I : Since the instruction set is simplified , Pipelining and common instructions can be executed by hardware ;

Performance characteristics II : Use a large number of registers , Enables most instruction operations to be performed between registers , Improved processing speed ;

Performance characteristics III :
Adopt cache — host — External memory three-level storage structure , Separate fetching and saving instructions , Enable the processor to do as much work as possible , The processing speed is not slowed down by accessing information from the memory . among ARM/MIPS/PowerPC They are based on the architecture of reduced instruction set machine processor ;X86 It is based on complex instruction set architecture ,Atom yes x86 Or x86 Compact version of instruction set .


According to various news ,Android Current status of supporting various processors :


ARM+Android Earliest development , Perfect support , Mainly in the mobile phone market , Netbook , Smart and other markets ;

X86+Android There is a relatively perfect development . yes atom+Android My netbook , And branch

Atom+Android and Atom+Window7 Dual system ;

MIPS+Android Currently in transplantation , In the process of improvement ;

Powpc+Android Currently in transplantation , In the process of improvement .


ARM Series processor


ARM framework , It used to be called an advanced reduced instruction set machine (Advanced RISC Machine, Earlier called :Acorn RISC
Machine), It's a 32 Bit reduced instruction set (RISC) Processor architecture , It is widely used in many embedded system designs .


Due to the characteristics of energy saving ,ARM The processor is very suitable for mobile communication , In line with its main design goal of low power consumption .


Today ,ARM The family has everything 32 Bit embedded processor 75% Proportion of , Make it the largest in the world 32 One of the bit architectures .


ARM Processors can be found in many consumer electronics products , From portable device (PDA, Mobile phone , Multimedia player , Handheld video game , And computers ) To computer peripherals ( Hard disk , Desktop router ), He even exists in military facilities such as missile borne computers .


Here are some based on ARM Derivative products of design , Important products also include Marvell of XScale Architecture and Texas Instruments OMAP series .


advantage : Low price , Low energy consumption ;

ARM Authorization method :ARM The company itself does not manufacture or sell by its own design CPU , Instead, the processor architecture is licensed to interested manufacturers .


ARM Provides a variety of licensing terms , Including items such as selling price and dissemination . For the Licensor ,ARM Provided ARM
Integrated hardware description of kernel , Contains complete software development tools ( compiler ,debugger,SDK), And for inclusion ARM CPU Right to sell silicon chips .


For licensors without fabs , It hopes to ARM The kernel is integrated into their own chip design , It is usually only aimed at obtaining a production ready smart core technology (IP Core) authentication .


For these customers ,ARM The selected will be released ARM Gate circuit diagram of core , Together with abstract simulation model and test program , To assist in design integration and verification .


Demand more customers , Including integrated component manufacturers (IDM) And wafer manufacturers , Select the composable RTL( Register transfer level , as Verilog) Form to obtain the intellectual property rights of the processor (IP).


Through integrable
RTL, Customers have the ability to optimize and strengthen the architecture . This approach allows designers to achieve additional design goals ( Such as high oscillation frequency , Low energy consumption , Instruction set extension, etc ) It will not be limited by the circuit diagram that cannot be changed .


although ARM The Licensor is not authorized to sell again ARM Architecture itself , However, the Licensor can sell the products at will ( Such as chip components , Evaluation board , Complete system, etc ).


Commercial Fabs are a special example , Because they can not only sell ARM Core silicon crystal finished product , For other customers , They usually retain reproductions ARM Kernel rights .


x86 series /Atom processor


x86 or 80x86 It's indale Intel First, a general term for microprocessor architecture developed and manufactured .


x86 Architecture is important for variable instruction length CISC( Complex instruction set computer ,Complex Instruction Set Computer).


Atom( chinese : AToM , Development code :Silverthorne) yes Intel An ultra low voltage processor family . Processor adoption 45 Nano process manufacturing , integrate 4700 Ten thousand transistors .L2 Cache as 512KB, support SSE3 Instruction set , and VT Virtualization Technology ( Some models ).


Now ,Atom Processor family 6 Models , All belong to Z500 series . They are Z500,Z510,Z520,Z530,Z540 and Z550. Lowest end Z500 The kernel frequency is 800MHz,FSB then is 400MHz. And the highest speed Z550, The kernel frequency is 2.0GHz,FSB then is 533MHz.


from Z520 start , All processors support hyper threading technology , But only less than 10% Power consumption of . Dual kernel version is N series , Still use 945GC Chipset .


The dual kernel version will still support hyper threading technology , So the system will show 4 Logical processor . The two kernels in this version are not designed locally , Just simply encapsulate two single cores .




MIPS Series processor


MIPS It is a very popular one in the world RISC processor .MIPS I mean “ Microprocessor without interlocked pipedstages ”(Microprocessor without
interlocked piped stages), The mechanism is to avoid data related problems in the pipeline by using software as much as possible .


It was first in 80 By Stanford in the early S (Stanford) university Hennessy Developed by a research team led by a professor .MIPS Corporate R Series is developed on this basis RISC Microprocessors for industrial products . These series of products are used by many computer companies to form various workstations and computer systems .


MIPS Technology company is a famous chip design company in the United States , It adopts reduced instruction system computing structure (RISC) To design the chip . And Intel's complex instruction system computing architecture (CISC) comparison ,RISC With simpler design , Shorter design cycle, etc , And more advanced technologies can be applied , Develop faster next-generation processors .


MIPS Is the earliest commercial RISC One of the architecture chips , The new architecture integrates all the original MIPS Instruction set , And added many more powerful functions .MIPS Do it yourself CPU Design of , Then authorize the design scheme to the customer , Enables customers to produce high-performance CPU.


1984 year ,MIPS Establishment of computer company , Start design RISC processor ;

1986 Launched in R2000 processor .

1992 year ,SGI Acquired MIPS Computer company .

1988 Annual push R3000 processor .

1991 First introduced in 64 Bit commercial microprocessor R4000; Then it was launched one after another R8000( to 1994 year ),R10000( to 1996 year ) and R12000( to 1997 year ) Equal model .


1998 year ,MIPS be divorced from SGI, become MIPS Technology company ; subsequently ,MIPS The company's strategy has changed , Focus on Embedded Systems ;1998 year -MIPS Technology stocks are publicly listed on the Nasdaq Stock Exchange .


1999 year ,MIPS Company release MIPS32 and MIPS64 Architecture standard , For the future MIPS It lays the foundation for the development of processor . The new architecture integrates all the original NIPS Instruction set , And added many more powerful functions .MIPS The company has successively developed high-performance products , Low power consumption 32 Bit processor core (core)MIPS324Kc And high performance 64 Bit processor core MIPS64

2000 year ,MIPS The company issued MIPS32 4Kc Version of and 64 position MIPS 64 20Kc Processor core .

2007 year 8 month 16 day -MIPS Technology announcement , The Godson CPU of the Computer Research Institute of the Chinese Academy of Sciences obtained its processor IP All patents and buses , Instruction set authorization .

2007 year 12 month 20 day -MIPS Technology announcement , Yangzhi technology has obtained its customized system single chip designed for advanced multimedia (SoC) core “MIPS32 24KEc Pro” to grant authorization .


PowerPC Series processor


PowerPC Is a reduced instruction set (RISC) CPU architecture (CPU), Its basic design comes from IBM( International Business Machines Corporation ) of IBM PowerPC 601
microprocessor POWER framework . 1990s ,IBM( International Business Machines Corporation ),Apple( Apple Inc ) and Motorola( Motorola ) Company development PowerPC Chip success , And manufactured based on PowerPC Multiprocessor computer .PowerPC The architecture is characterized by good scalability , Convenient and flexible .


PowerPC Processors have a wide range of implementations , Including from such as Power4 High end servers like that CPU To embedded CPU market ( Nintendo Gamecube Used
PowerPC).PowerPC The processor has very strong embedded performance , Because it has excellent performance , Lower energy loss and lower heat dissipation . In addition to integration like serial and Ethernet controllers
I/O, The embedded processor and “ Desktop ”CPU There is a very significant difference .


Real time (Real Time)DSP framework


DSP It is a kind of microprocessor , This microprocessor has extremely high processing speed . Because the application of this kind of processor requires high real-time performance (Real
Time). For example, call through mobile phone , If the processing speed is not fast, you can only wait for the other party to stop talking , This party can talk .


If both sides talk at the same time , Because the speed of digital signal processing is not enough , You can only turn off the signal connection . stay DSP Before the emergence of digital signal processing can only rely on MPU( microprocessor ) To complete . but MPU Low processing speed can not meet the requirements of high-speed real-time .


therefore , until 70 years , Someone put forward DSP Theoretical and algorithmic basis of . At that time DSP Just stay in textbooks , Even developed DSP The system is also composed of discrete components , Its application is limited to military , Aerospace sector .


90 years DSP Fastest development , The fourth and fifth generations have emerged one after another DSP device . current DSP It belongs to the fifth generation product , Compared with the fourth generation , Higher system integration , take DSP The core and peripheral components are integrated on a single chip . This highly integrated DSP The chip is not only in communication , Show your skills in the computer field , And gradually penetrated into the field of people's daily consumption .