Opcode Prefix
In computing, an opcode prefix is an numeric value that alters the function of a following opcode. On some instruction set architectures multiple opcode prefixes are allowed sequentially, with all combining to alter the subsequent opcode. The opcode prefix is a portion of a larger machine language instruction that specifies the operation to be performed. In addition to the opcode, some instructions specify the operands the operation will act upon. Opcode prefixes may alter the number or size of the operands. RISC processors do not use opcode prefixes. Types of prefixes Opcode prefixes generally fall into two categories: # Opcode prefixes that alter subsequent opcode functions. # Opcode prefixes that enable an alternate set of opcodes. This is analogous to the shift key on a keyboard. In this way, instruction sets can be extended by adding a subset of new instructions by reusing existing reserved opcodes. Example opcode prefixes The following is not intended to be an exhaustiv ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Computing
Computing is any goal-oriented activity requiring, benefiting from, or creating computer, computing machinery. It includes the study and experimentation of algorithmic processes, and the development of both computer hardware, hardware and software. Computing has scientific, engineering, mathematical, technological, and social aspects. Major computing disciplines include computer engineering, computer science, cybersecurity, data science, information systems, information technology, and software engineering. The term ''computing'' is also synonymous with counting and calculation, calculating. In earlier times, it was used in reference to the action performed by Mechanical computer, mechanical computing machines, and before that, to Computer (occupation), human computers. History The history of computing is longer than the history of computing hardware and includes the history of methods intended for pen and paper (or for chalk and slate) with or without the aid of tables. ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Binary-code Compatibility
Binary-code compatibility (binary compatible or object-code compatible) is a property of a computer system, meaning that it can run the same executable code, typically machine code for a general-purpose computer central processing unit (CPU), that another computer system can run. Source-code compatibility, on the other hand, means that recompilation or interpretation is necessary before the program can be run on the compatible system. For a compiled program on a general operating system, binary compatibility often implies that not only the CPUs ( instruction sets) of the two computers are binary compatible, but also that interfaces and behaviours of the operating system (OS) and application programming interfaces (APIs), and the application binary interfaces (ABIs) corresponding to those APIs, are sufficiently equal, i.e. "compatible". A term like backward-compatible usually implies object-code compatibility. This means that newer computer hardware and/or software has (pra ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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AMD Opteron
Opteron is AMD's x86 former server and workstation processor line, and was the first processor which supported the AMD64 instruction set architecture (known generically as x86-64). It was released on April 22, 2003, with the ''SledgeHammer'' core (K8) and was intended to compete in the server and workstation markets, particularly in the same segment as the Intel Xeon processor. Processors based on the AMD K10 microarchitecture (codenamed ''Barcelona'') were announced on September 10, 2007, featuring a new quad-core configuration. The last released Opteron CPUs are the Piledriver-based Opteron 4300 and 6300 series processors, codenamed "Seoul" and "Abu Dhabi" respectively. In January 2016, the first ARMv8-A based Opteron-branded SoC was released, though it is unclear what, if any, heritage this Opteron-branded product line shares with the original Opteron technology other than intended use in the server space. Technical description Key capabilities Opteron combines two im ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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X86-64
x86-64 (also known as x64, x86_64, AMD64, and Intel 64) is a 64-bit extension of the x86 instruction set architecture, instruction set. It was announced in 1999 and first available in the AMD Opteron family in 2003. It introduces two new operating modes: 64-bit mode and compatibility mode, along with a new four-level paging mechanism. In 64-bit mode, x86-64 supports significantly larger amounts of virtual memory and physical memory compared to its 32-bit computing, 32-bit predecessors, allowing programs to utilize more memory for data storage. The architecture expands the number of general-purpose registers from 8 to 16, all fully general-purpose, and extends their width to 64 bits. Floating-point arithmetic is supported through mandatory SSE2 instructions in 64-bit mode. While the older x87 FPU and MMX registers are still available, they are generally superseded by a set of sixteen 128-bit Processor register, vector registers (XMM registers). Each of these vector registers ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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AMD64
x86-64 (also known as x64, x86_64, AMD64, and Intel 64) is a 64-bit extension of the x86 instruction set. It was announced in 1999 and first available in the AMD Opteron family in 2003. It introduces two new operating modes: 64-bit mode and compatibility mode, along with a new four-level paging mechanism. In 64-bit mode, x86-64 supports significantly larger amounts of virtual memory and physical memory compared to its 32-bit predecessors, allowing programs to utilize more memory for data storage. The architecture expands the number of general-purpose registers from 8 to 16, all fully general-purpose, and extends their width to 64 bits. Floating-point arithmetic is supported through mandatory SSE2 instructions in 64-bit mode. While the older x87 FPU and MMX registers are still available, they are generally superseded by a set of sixteen 128-bit vector registers (XMM registers). Each of these vector registers can store one or two double-precision floating-point numbers, ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Intel 8088
The Intel 8088 ("''eighty-eighty-eight''", also called iAPX 88) microprocessor is a variant of the Intel 8086. Introduced on June 1, 1979, the 8088 has an eight-bit external data bus instead of the 16-bit bus of the 8086. The 16-bit registers and the one megabyte address range are unchanged, however. In fact, according to the Intel documentation, the 8086 and 8088 have the same execution unit (EU)—only the bus interface unit (BIU) is different. The 8088 was used in the original IBM PC and in IBM PC compatible clones. History and description The 8088 was designed at Intel's laboratory in Haifa, Israel, as were a large number of Intel's processors. The 8088 was targeted at economical systems by allowing the use of an eight-bit data path and eight-bit support and peripheral chips; complex circuit boards were still fairly cumbersome and expensive when it was released. The prefetch queue of the 8088 was shortened to four bytes, from the 8086's six bytes, and the prefe ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Intel 8086
The 8086 (also called iAPX 86) is a 16-bit computing, 16-bit microprocessor chip designed by Intel between early 1976 and June 8, 1978, when it was released. The Intel 8088, released July 1, 1979, is a slightly modified chip with an external 8-bit Bus (computing), data bus (allowing the use of cheaper and fewer supporting Integrated circuit, ICs),Fewer TTL buffers, latches, multiplexers (although the amount of TTL logic was not drastically reduced). It also permits the use of cheap 8080-family ICs, where the 8254 CTC, Intel 8255, 8255 PIO, and 8259 PIC were used in the IBM PC design. In addition, it makes PCB layout simpler and boards cheaper, as well as demanding fewer (1- or 4-bit wide) DRAM chips. and is notable as the processor used in the original IBM Personal Computer, IBM PC design. The 8086 gave rise to the x86 architecture, which eventually became Intel's most successful line of processors. On June 5, 2018, Intel released a limited-edition CPU celebrating the 40th anniv ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Zilog
Zilog, Inc. is an American manufacturer of microprocessors, microcontrollers, and application-specific embedded System on a chip, system-on-chip (SoC) products. The company was founded in 1974 by Federico Faggin and Ralph Ungermann, who were soon joined by Masatoshi Shima. All three had left Intel after working on the Intel 4004, 4004 and Intel 8080, 8080 microprocessors. The company's most famous product is the Zilog Z80, Z80 microprocessor, which played an important role in the evolution of early computing. Backward compatible, Software-compatible with the Intel 8080, it offered a compelling alternative due to its lower cost and increased performance, propelling it to widespread adoption in video game systems and home computers during the late 1970s and early 1980s. The name, pronounced with a long "i" (), is an acronym of ''Z integrated logic'', also thought of as "Z for the last word of Integrated Logic". History Zilog was started in California in 1974 by Federico Faggin and ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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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]   |
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Zilog Z80
The Zilog Z80 is an 8-bit computing, 8-bit microprocessor designed by Zilog that played an important role in the evolution of early personal computing. Launched in 1976, it was designed to be Backward compatibility, software-compatible with the Intel 8080, offering a compelling alternative due to its better Integrated circuit, integration and increased performance. Along with the 8080's seven Processor register, registers and flags register, the Z80 introduced an alternate register set, two 16-bit index registers, and additional instructions, including bit manipulation and block copy/search. Originally intended for use in embedded systems like the 8080, the Z80's combination of compatibility, affordability, and superior performance led to widespread adoption in video game systems and home computers throughout the late 1970s and early 1980s, helping to fuel the personal computing revolution. The Z80 was used in iconic products such as the Osborne 1, TRS-80, Radio Shack TRS-80, Col ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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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]   |