CPU design

CPU design - 1950s: early designs. Each of the computer designs of the early 1950s was a unique design; there were no upward-compatible machines or computer architectures with multiple, differing implementations. Programs written for one machine would not run on another kind, even other kinds from the same company. This was not a major drawback at the time because there was not a large body of software developed to run on computers, so star ...

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CPU design, CPU design - Goals of CPU design, CPU design - History of general purpose CPUs, CPU design - 1950s: early designs, CPU design - 1960s: the computer revolution and CISC, CPU design - 1970s: large scale integration, CPU design - Early 1980s: the lessons of RISC, CPU design - Mid-1980s to today: exploiting instruction level parallelism, CPU design - 1990 to today: looking forward, CPU design - Embedded design, CPU design - Other design issues, CPU design - Design concepts, CPU design - RISC, CPU design - Instruction pipelining, CPU design - Cache, CPU design - Superscalar designs, CPU design - Out-of-order execution, CPU design - Speculative execution, CPU design - Multiprocessing and Multithreading

Read more here: » CPU design: Encyclopedia II - CPU design - History of general purpose CPUs

CPU design - 1950s: early designs. Each of the computer designs of the early 1950s was a unique design; there were no upward-compatible machines or computer architectures with multiple, differing implementations. Programs written for one machine would not run on another kind, even other kinds from the same company. This was not a major drawback at the time because there was not a large body of software developed to run on computers, so star ...

See also:

CPU design, CPU design - History of general purpose CPUs, CPU design - 1950s: early designs, CPU design - 1960s: the computer revolution and CISC, CPU design - 1970s: large scale integration, CPU design - Early 1980s: the lessons of RISC, CPU design - Mid-1980s to today: exploiting instruction level parallelism, CPU design - 1990 to today: looking forward, CPU design - Embedded design, CPU design - Other design issues, CPU design - Design concepts, CPU design - RISC, CPU design - Instruction pipelining, CPU design - Speculative execution, CPU design - Cache, CPU design - Out-of-order execution, CPU design - Superscalar designs, CPU design - Simultaneous multithreading

Read more here: » CPU design: Encyclopedia II - CPU design - History of general purpose CPUs

Central processing unit - Integer precision. The way a CPU represents numbers is a design choice that affects the most basic ways in which the device functions. Some early digital computers used an electrical model of the common decimal (base ten) numeral system to represent numbers internally. A few other computers have used more exotic numeral systems like ternary (base three). Nearly all modern CPUs represent numbers in binary form, with each digit being represented by some two-valued physical quantity such as a "high" or "low" voltage. ^{See also:}

Central processing unit, Central processing unit - History, Central processing unit - Discrete transistor and IC CPUs, Central processing unit - Microprocessors, Central processing unit - CPU operation, Central processing unit - Design and implementation, Central processing unit - Integer precision, Central processing unit - Clock rate, Central processing unit - Parallelism, Central processing unit - Vector processors and SIMD, Central processing unit - Notes

Read more here: » Central processing unit: Encyclopedia II - Central processing unit - Design and implementation

A central processing unit (CPU), or sometimes simply processor, is the component in a digital computer that interprets and executes instructions and data contained in software. CPUs provide the fundamental digital computer trait of programmability, and are one of the core components found in almost all modern microcomputers, along with primary storage and input/output facilities. In a similar vein, microprocessors are a type of CPU that is manufactured on an integrated circuit, often as a single-chip package. Since the m ...

Including:

• Central processing unit - History
• Central processing unit - Discrete transistor and IC CPUs
• Central processing unit - Microprocessors
• Central processing unit - CPU operation
• Central processing unit - Design and implementation
• Central processing unit - Integer precision
• Central processing unit - Clock rate
• Central processing unit - Parallelism
• Central processing unit - Vector processors and SIMD
• Central processing unit - Notes

Read more here: » Central processing unit: Encyclopedia - Central processing unit

In computer science, computer architecture is the conceptual design and fundamental operational structure of a computer system. It is a blueprint and functional description of requirements (especially speeds and interconnections) and design implementations for the various parts of a computer —focusing largely on the way by which the CPU performs internally and accesses addresses in memory. "Architecture" hence typically refers to the fixed internal structure of the CPU (ie. electronic switches to represent logic gates) to per ...

Including:

• Computer architecture - Design goals
• Computer architecture - Cost
• Computer architecture - Performance
• Computer architecture - Virtual memory
• Computer architecture - Computer architecture on a future horizon

Read more here: » Computer architecture: Encyclopedia - Computer architecture

A Complex Instruction Set Core (CISC) is a microprocessor instruction set architecture (ISA) in which each instruction can execute several low-level operations, such as a load from memory, an arithmetic operation, and a memory store, all in a single instruction. The term was coined in contrast to Reduced Instruction Set Computer (RISC). Before the first RISC processors were designed, many computer architects tried to bridge the "semantic gap" - to design instruction sets to support high-level programming languages by providing ...

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Virtual memory or virtual memory addressing is a memory management technique, used by multitasking computer operating systems wherein non-contiguous memory is presented to a software application (aka process) as contiguous memory. The contiguous memory is referred to as the virtual address space. Virtual memory addressing is typically used in paged memory systems. This in turn is often combined with memory swapping, whereby memory pages stored in primary storage are written to secondary storage, thus freei ...

Including:

• Virtual memory - Background
• Virtual memory - Segmentation
• Virtual memory - Basic operation
• Virtual memory - Details
• Virtual memory - Paging and virtual memory
• Virtual memory - Additional details
• Virtual memory - History
• Virtual memory - Windows example
• Virtual memory - Misconceptions about the Windows page file
• Virtual memory - Virtual Memory in Linux

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Most computers possess four kinds of memory: registers in the CPU, CPU caches (generally some kind of static RAM) both inside and adjacent to the CPU, main memory (generally dynamic RAM) which the CPU can read and write to directly and reasonably quickly; and disk storage, which is much slower, but also much larger. CPU register use is generally handled by the compiler and this isn't a huge burden as data doesn't generally stay in them very long. The decision of when to use cache and when to use main memory is generally dealt with by hardware so generally both are regarded together ...

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Virtual memory, Virtual memory - Background, Virtual memory - Segmentation, Virtual memory - Basic operation, Virtual memory - Details, Virtual memory - Paging and virtual memory, Virtual memory - Additional details, Virtual memory - History, Virtual memory - Windows example, Virtual memory - Misconceptions about the Windows page file, Virtual memory - Virtual Memory in Linux

Read more here: » Virtual memory: Encyclopedia II - Virtual memory - Background

Prior to the advent of machines that resemble today's CPUs, computers such as ENIAC had to be physically rewired in order to perform different tasks. These machines are often referred to as "fixed-program computers," since they had to be physically reconfigured in order to run a different program. Since the term "CPU" is generally defined as a software (computer program) execution device, the earliest devices that could rightly be called CPUs c ...

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Central processing unit, Central processing unit - History, Central processing unit - Discrete transistor and IC CPUs, Central processing unit - Microprocessors, Central processing unit - CPU operation, Central processing unit - Design and implementation, Central processing unit - Integer precision, Central processing unit - Clock rate, Central processing unit - Parallelism, Central processing unit - Vector processors and SIMD, Central processing unit - Notes

Read more here: » Central processing unit: Encyclopedia II - Central processing unit - History

The most common goals in computer architecture revolve around the tradeoffs between cost and performance (i.e. speed), although other considerations, such as size, weight, reliability, feature set, expandability and power consumption, may be factors as well. Computer architecture - Cost. Generally cost is held constant, determined by either system or commercial requirements, and speed and storage capacity are adjusted to meet the cost target. ...

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Computer architecture, Computer architecture - Design goals, Computer architecture - Cost, Computer architecture - Performance, Computer architecture - Virtual memory, Computer architecture - Computer architecture on a future horizon

Read more here: » Computer architecture: Encyclopedia II - Computer architecture - Design goals

This is an example NASM-syntax self-modifying x86-assembly algorithm that determines the size of the PIQ: code_starts_here: xor cx, cx ; zero register cx xor ax, ax ; zero register ax mov dx, cs ; change dx to edx for protected mode. mov [code_segment], dx ; "calculate" codeseg in the far jump below (edx here too) around: cmp ax, 1 ; check if ax has been alterd je found_size mov [nop_field+cx], 0x90 ; 0x90 = opcode "nop" (NO oPerati ...

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Prefetch input queue, Prefetch input queue - x86 example code, Prefetch input queue - Example program to detect the size of the PIQ

Read more here: » Prefetch input queue: Encyclopedia II - Prefetch input queue - Example program to detect the size of the PIQ

The earliest Pentiums were released at the clock speeds of 66 MHz and 60 MHz. Later on 75, 90, 100, 120, 133, 150, 166, 200, and 233 MHz versions gradually became available. 266 and 300 MHz versions were later released for mobile computing. Pentium OverDrive processors were released at speeds of 63 and 83 MHz as an upgrade option for older 486-class computers. Pentium - P5 P54 P54C. The original Pentium microprocessor had the internal code name P5, and was a pipelined in-order superscalar microprocessor, p ...

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Pentium, Pentium - Major changes from the 486, Pentium - Models, Pentium - P5 P54 P54C, Pentium - P55C Tillamook, Pentium - Other uses of Pentium trademark

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The earliest Pentiums were released at the clock speeds of 66 MHz and 60 MHz. Later on 75, 90, 100, 120, 133, 150, 166, 200, and 233 MHz versions gradually became available. 266 and 300 MHz versions were later released for mobile computing. Pentium OverDrive processors were released at speeds of 63 and 83MHz as an upgrade option for older 486-class computers. Pentium - P5 P54 P54C. The original Pentium microprocessor had the internal code name P5, and was a pipelined in-order superscalar microprocessor, pr ...

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Pentium, Pentium - Major changes from the 486, Pentium - Models, Pentium - P5 P54 P54C, Pentium - P55C Tillamook, Pentium - Other uses of Pentium trademark

Read more here: » Pentium: Encyclopedia II - Pentium - Models

Microprocessor - The first microprocessors. As with many advances in technology, the microprocessor was an idea whose time had come. Three projects arguably delivered a complete microprocessor at about the same time, Intel's 4004, Texas Instruments' TMS 1000, and Garrett AiResearch's Central Air Data Computer. In 1968, Garrett was invited to produce a digital computer to compete with electromechanical systems then under development for the main flight control computer in the US Navy's new F-14 Tomcat fight ...

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Microprocessor, Microprocessor - History, Microprocessor - The first microprocessors, Microprocessor - Notable 8-bit designs, Microprocessor - 16-bit designs, Microprocessor - 32-bit designs, Microprocessor - 64-bit microchips on the desktop, Microprocessor - RISC, Microprocessor - Special-purpose microprocessors, Microprocessor - Design concepts, Microprocessor - Market statistics, Microprocessor - Common µPs; architectures, Microprocessor - Notes

Read more here: » Microprocessor: Encyclopedia II - Microprocessor - History

Central processing unit - Integer precision. The way a CPU represents numbers is a design choice that affects the most basic ways in which the device functions. Some early digital computers used an electrical model of the common decimal (base ten) numeral system to represent numbers internally. A few other computers have used more exotic numeral systems like ternary (base three). Nearly all modern CPUs represent numbers in binary form, with each digit being represented by some two-valued physical quantity such as a "h ...

See also:

Central processing unit, Central processing unit - History, Central processing unit - Discrete transistor and IC CPUs, Central processing unit - Microprocessors, Central processing unit - CPU operation, Central processing unit - Design and implementation, Central processing unit - Integer precision, Central processing unit - Clock rate, Central processing unit - Parallelism, Central processing unit - Vector processors and SIMD, Central processing unit - Notes

Read more here: » Central processing unit: Encyclopedia II - Central processing unit - Design and implementation

code_starts_here: mov eax, ahead mov [eax], 0x9090 ahead: jmp near to_the_end ; Some other code to_the_end: This self-modifying program will overwrite the jmp to_the_end with two NOPs (which is encoded as 0x9090). The jump jmp near to_the_end is assembled into two bytes of machinecode, so the two NOPs will just overwrite this jump and nothing else. (That is, the jump is replaced with an do-nothing-code.) Because the machine code of the jump is already read into the PIQ, and probably also ...

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Prefetch input queue, Prefetch input queue - x86 example code, Prefetch input queue - Example program to detect the size of the PIQ

Read more here: » Prefetch input queue: Encyclopedia II - Prefetch input queue - x86 example code

The fundamental operation of most CPUs, regardless of the physical form they take, is to execute a sequence of stored instructions called a program. Discussed here are devices that conform to the common Von Neumann architecture. The program is represented by a series of numbers that are kept in some kind of computer memory. There are four steps that nearly all Von Neumann CPUs use in their operation: fetch< ...

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Central processing unit, Central processing unit - History, Central processing unit - Discrete transistor and IC CPUs, Central processing unit - Microprocessors, Central processing unit - CPU operation, Central processing unit - Design and implementation, Central processing unit - Integer precision, Central processing unit - Clock rate, Central processing unit - Parallelism, Central processing unit - Vector processors and SIMD, Central processing unit - Notes

Read more here: » Central processing unit: Encyclopedia II - Central processing unit - CPU operation

A control unit is the part of a CPU or other device that directs its operation. The outputs of the unit control the activity of the rest of the device. A control unit can be thought of as a finite state machine. At one time control units for CPUs were ad-hoc logic, and they were difficult to design. Now they are often implemented as a microprogram that is stored in a control store. Words of the microprogram are selected by a microsequencer and the bits from those words directly control the different parts of the device, includi ...

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The VIA C3 is an x86 central processing unit for personal computers produced by VIA Technologies. Although the predecessor to the VIA C3 was called the "VIA Cyrix III," both it and the VIA C3 are based on the CPU design technology of Centaur Technology, makers of the WinChip C6. VIA bought Centaur from IDT. As of March 2004 the fastest edition currently available works at the speed of 1.4 GHz with a 133 MHz front side bus on a Socket 370 motherboard or factory soldered EBGA on Mini-ITX mainboards. Both fanless and fan ...

Including:

• VIA C3 - Core development
• VIA C3 - Processor table
• VIA C3 - Roadmap changes
• VIA C3 - Comparative die size
• VIA C3 - Design methodology
• VIA C3 - Contracts

Read more here: » VIA C3: Encyclopedia - VIA C3

Prior to the advent of machines that resemble today's CPUs, computers such as ENIAC had to be physically rewired in order to perform different tasks. These machines are often referred to as "fixed-program computers," since they had to be physically reconfigured in order to run a different program. Since the term "CPU" is generally defined as a software (computer program) execution device, the earliest devices that could rightly be called CPUs came with the advent of the stored-program computer. The idea of a stored-program computer wa ...

See also:

Central processing unit, Central processing unit - History, Central processing unit - Discrete transistor and IC CPUs, Central processing unit - Microprocessors, Central processing unit - CPU operation, Central processing unit - Design and implementation, Central processing unit - Integer precision, Central processing unit - Clock rate, Central processing unit - Parallelism, Central processing unit - Vector processors and SIMD, Central processing unit - Notes

Read more here: » Central processing unit: Encyclopedia II - Central processing unit - History