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NOP (code)
In computer science, a NOP, no-op, or NOOP (pronounced "no op"; short for no operation) is a machine language instruction and its assembly language mnemonic, programming language statement, or computer protocol command that does nothing. Machine language instructions Some computer instruction sets include an instruction whose purpose is to not change the state of any of the programmer-accessible registers, status flags, or memory. It often takes a well-defined number of clock cycles to execute. In other instruction sets, there is no explicit NOP instruction, but the assembly language mnemonic NOP represents an instruction which acts as a NOP; e.g., on the SPARC, sethi 0, %g0. A NOP must not access memory, as that could cause a memory fault or page fault. A NOP is most commonly used for timing purposes, to force memory alignment, to prevent hazards, to occupy a branch delay slot, to render void an existing instruction such as a jump, as a target of an execute i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Science
Computer science is the study of computation, information, and automation. Computer science spans Theoretical computer science, theoretical disciplines (such as algorithms, theory of computation, and information theory) to Applied science, applied disciplines (including the design and implementation of Computer architecture, hardware and Software engineering, software). Algorithms and data structures are central to computer science. The theory of computation concerns abstract models of computation and general classes of computational problem, problems that can be solved using them. The fields of cryptography and computer security involve studying the means for secure communication and preventing security vulnerabilities. Computer graphics (computer science), Computer graphics and computational geometry address the generation of images. Programming language theory considers different ways to describe computational processes, and database theory concerns the management of re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Motorola 68000
The Motorola 68000 (sometimes shortened to Motorola 68k or m68k and usually pronounced "sixty-eight-thousand") is a 16/32-bit complex instruction set computer (CISC) microprocessor, introduced in 1979 by Motorola Semiconductor Products Sector. The design implements a 32-bit instruction set, with 32-bit registers and a 16-bit internal data bus. The address bus is 24 bits and does not use memory segmentation, which made it easier to program for. Internally, it uses a 16-bit data arithmetic logic unit (ALU) and two more 16-bit ALUs used mostly for addresses, and has a 16-bit external data bus. For this reason, Motorola termed it a 16/32-bit processor. As one of the first widely available processors with a 32-bit instruction set, large unsegmented address space, and relatively high speed for the era, the 68k was a popular design through the 1980s. It was widely used in a new generation of personal computers with graphical user interfaces, including the Macintosh 128K, Amiga, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intel 8085
The Intel 8085 ("''eighty-eighty-five''") is an 8-bit microprocessor produced by Intel and introduced in March 1976. It is software-binary-code compatibility, binary compatible with the more-famous Intel 8080. It is the last 8-bit microprocessor developed by Intel. The "5" in the part number highlighted the fact that the 8085 uses a single +5-volt (V) power supply, compared to the 8080's +5, -5 and +12V, which makes the 8085 easier to integrate into systems that by this time were mostly +5V. The other major change was the addition of a serial port, with separate input and output pins. This was often all that was needed in simple systems and eliminated the need for separate integrated circuits to provide this functionality, as well as simplifying the computer bus as a result. The only changes in the instruction set compared to the 8080 were instructions for reading and writing data using these pins. The 8085 is supplied in a 40-pin Dual in-line package, DIP package. Given the n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intel 8080
The Intel 8080 is Intel's second 8-bit computing, 8-bit microprocessor. Introduced in April 1974, the 8080 was an enhanced successor to the earlier Intel 8008 microprocessor, although without binary compatibility.'' Electronic News'' was a weekly trade newspaper. The same advertisement appeared in the :File:Intel 8080 Advertisement May 1974.jpg, May 2, 1974, issue of ''Electronics'' magazine. Originally intended for use in Embedded system, embedded systems such as calculators, cash registers, computer terminals, and industrial robots, its robust performance soon led to adoption in a broader range of systems, ultimately helping to launch the microcomputer industry. Several key design choices contributed to the 8080’s success. Its 40‑pin package simplified interfacing compared to the 8008’s 18‑pin design, enabling a more efficient data bus. The transition to NMOS logic, NMOS technology provided faster transistor speeds than the 8008's PMOS logic, PMOS while also simplifyin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MCS-51
The Intel MCS-51 (commonly termed 8051) is a single-chip microcontroller (MCU) series developed by Intel in 1980 for use in embedded systems. The architect of the Intel MCS-51 instruction set was John H. Wharton.. Intel's original versions were popular in the 1980s and early 1990s, and enhanced binary compatible derivatives remain popular today. It is a complex instruction set computer with separate memory spaces for program instructions and data. Intel's original MCS-51 family was developed using N-type metal–oxide–semiconductor ( NMOS) technology, like its predecessor Intel MCS-48, but later versions, identified by a letter C in their name (e.g., 80C51) use complementary metal–oxide–semiconductor (CMOS) technology and consume less power than their NMOS predecessors. This made them more suitable for battery-powered devices. The family was continued in 1996 with the enhanced 8-bit MCS-151 and the 8/ 16/32-bit MCS-251 family of binary compatible microcontrollers. Whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intel 8008
The Intel 8008 ("''eight-thousand-eight''" or "''eighty-oh-eight''") is an early 8-bit microprocessor capable of addressing 16 KB of memory, introduced in April 1972. The 8008 architecture was designed by Computer Terminal Corporation (CTC) and was implemented and manufactured by Intel. While the 8008 was originally designed for use in CTC's Datapoint 2200 programmable terminal, an agreement between CTC and Intel permitted Intel to market the chip to other customers after Seiko expressed an interest in using it for a calculator. History In order to address several issues with the Datapoint 3300, including excessive heat radiation, Computer Terminal Corporation (CTC) designed the architecture of the 3300's planned successor with a CPU as part of the internal circuitry re-implemented on a single chip. Looking for a company able to produce their chip design, CTC co-founder Austin O. "Gus" Roche turned to Intel, then primarily a vendor of memory chips. Roche met with Bob Noyce, who ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ModR/M
The ModR/M byte is an important part of instruction encoding for the x86 instruction set. Description Opcodes in x86 are generally one-byte, though two-byte instructions and prefixes exist. ModR/M is a byte that, if required, follows the opcode and specifies zero, one, or two operands for the instruction. The format is: The "reg" field, if specifying an operand, encodes the three least-significant bits of a register index. Which register (general purpose, AVX, etc.) depends on the instruction being executed.register mapping (with various columns depending on type)? --> Instructions which take only one operand typically do not use this field, but instead repurpose the bits as an "opcode extension", allowing eight instructions to share a single opcode byte. In opcode listings, these are specified by following the opcode with a slash () and a digit 0-7. For example, the opcode for byte increment is , while for byte decrement it is . The "mod" field specifies the addressing mode ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentium Pro
The Pentium Pro is a sixth-generation x86 microprocessor developed and manufactured by Intel and introduced on November 1, 1995. It implements the P6 (microarchitecture), P6 microarchitecture (sometimes termed i686), and was the first x86 Intel CPU to do so. The Pentium Pro was originally intended to replace the original Pentium (original), Pentium in a full range of applications. Later, it was reduced to a more narrow role as a server and high-end desktop processor. The Pentium Pro was also used in supercomputers, most notably ASCI Red, which was the first computer to reach over one teraFLOPS in 1996 and held the number one spot in the TOP500 list from 1997 to 2000. ASCI Red used two Pentium Pro CPUs on each computing node. While the Pentium and Pentium MMX had 3.1 and 4.5 million transistors, respectively, the Pentium Pro contained 5.5 million transistors. It was capable of both dual- and quad-processor configurations and only came in one form factor, the relatively l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Processing Unit
A central processing unit (CPU), also called a central processor, main processor, or just processor, is the primary Processor (computing), processor in a given computer. Its electronic circuitry executes Instruction (computing), instructions of a computer program, such as arithmetic, logic, controlling, and input/output (I/O) operations. This role contrasts with that of external components, such as main memory and I/O circuitry, and specialized coprocessors such as graphics processing units (GPUs). The form, CPU design, design, and implementation of CPUs have changed over time, but their fundamental operation remains almost unchanged. Principal components of a CPU include the arithmetic–logic unit (ALU) that performs arithmetic operation, arithmetic and Bitwise operation, logic operations, processor registers that supply operands to the ALU and store the results of ALU operations, and a control unit that orchestrates the #Fetch, fetching (from memory), #Decode, decoding and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intel
Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California, and Delaware General Corporation Law, incorporated in Delaware. Intel designs, manufactures, and sells computer components such as central processing units (CPUs) and related products for business and consumer markets. It is one of the world's List of largest semiconductor chip manufacturers, largest semiconductor chip manufacturers by revenue, and ranked in the Fortune 500, ''Fortune'' 500 list of the List of largest companies in the United States by revenue, largest United States corporations by revenue for nearly a decade, from 2007 to 2016 Fiscal year, fiscal years, until it was removed from the ranking in 2018. In 2020, it was reinstated and ranked 45th, being the List of Fortune 500 computer software and information companies, 7th-largest technology company in the ranking. It was one of the first companies listed on Nasdaq. Intel supplies List of I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Opcode
In computing, an opcode (abbreviated from operation code) is an enumerated value that specifies the operation to be performed. Opcodes are employed in hardware devices such as arithmetic logic units (ALUs), central processing units (CPUs), and software instruction sets. In ALUs, the opcode is directly applied to circuitry via an input signal bus. In contrast, in CPUs, the opcode is the portion of a machine language instruction that specifies the operation to be performed. CPUs Opcodes are found in the machine language instructions of CPUs as well as in some abstract computing machines. In CPUs, an opcode may be referred to as an instruction machine code, instruction code, instruction syllable, instruction parcel, or opstring. For any particular processor (which may be a general CPU or a more specialized processing unit), the opcodes are defined by the processor's instruction set architecture (ISA). They can be described using an opcode table. The types of operations may in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
