Searches , social queries for OPCODE
Search references for OPCODE. Phrases containing OPCODE
See searches and references containing OPCODE!
Search references for OPCODE. Phrases containing OPCODE
See searches and references containing OPCODE!OPCODE
Part of a machine instruction
In computing, an opcode (abbreviated from operation code) is an enumerated value that specifies the operation to be performed. Opcodes are employed in
Opcode
Part of a computer instruction
an opcode prefix is a numeric prefix code that alters the function of a following opcode. On some instruction set architectures multiple opcode prefixes
Opcode_prefix
Instructions directly executable by a computer
possible through opcode-level programming to deliberately arrange the resulting code so that two code paths share a common fragment of opcode sequences. These
Machine_code
Undocumented CPU instruction that has an effect
In computer science, an illegal opcode, also called an unimplemented operation, unintended opcode or undocumented instruction, is an instruction to a
Illegal_opcode
American music software company
Opcode Systems, Inc. was an American music software company founded in 1985 by Dave Oppenheim and based in and around Palo Alto, California, USA. Opcode
Opcode_Systems
Visual representation of all opcodes in an instruction set
An opcode table (also called an opcode matrix) is a visual representation of all opcodes in an instruction set. It is arranged such that each axis of
Opcode_table
Low-level programming language family
Assembly language uses mnemonics to represent low-level machine instructions (opcodes), directives, and usually architectural registers and flags. Some of the
Assembly_language
List of x86 microprocessor instructions
(6 bits for opcode C1 if it is encoded with a 64-bit operand-size under x86-64) On 80186 and later, sub-opcode /6 for the shift-opcodes C0/C1/D0/D1/D2/D3
List_of_x86_instructions
Set of x86 processor instructions
The Intel BCD opcodes are a set of six x86 instructions that operate with binary-coded decimal numbers: AAA, DAA, AAS, DAS, AAM, and AAD. Most arithmetic
Intel_BCD_opcodes
Computer assembly language instruction
SIGTRAP. The opcode for INT3 is 0xCC, as opposed to the opcode for INT immediate8, which is 0xCD immediate8. Since the dedicated 0xCC opcode has some desired
INT_(x86_instruction)
Computer network protocol
and opcode ≠ 0. A fragmented message consists of one frame with FIN = 0 and opcode ≠ 0, followed by zero or more frames with FIN = 0 and opcode = 0,
WebSocket
Programmable machine that processes data
code or opcode for short). The command to add two numbers together would have one opcode; the command to multiply them would have a different opcode, and
Computer
Combinational digital circuit
called operands, and a code indicating the operation to be performed (opcode); the ALU's output is the result of the performed operation. In many designs
Arithmetic_logic_unit
CPU optimization unit
Fetching the instruction opcodes from program memory well in advance is known as prefetching and it is served by using a prefetch input queue (PIQ). The
Prefetch_input_queue
36-bit computer by Digital (1966–1983)
general instructions, the leftmost 9 bits, 0 to 8, contain an instruction opcode. Many of the possible 512 codes are not defined in the base model machines
PDP-10
Interpreted programming language
the semantics of a few of the opcodes, and SCHIP continued to use those new semantics in addition to changing other opcodes. Many online resources about
CHIP-8
Single chip microcontroller series by Intel
initial opcode byte, followed by up to 2 bytes of operands. 1⁄4 of the opcode bytes, x0–x3, are used for irregular opcodes. 3⁄4 of the opcode bytes, x4–xF
Intel_MCS-51
Microprocessor instruction set
single byte opcodes (the "root instructions"), most of which are inherited from the 8080. The four remaining codes are used extensively as opcode prefixes:
Z80_instruction_set
Computer security testing tool
against a remote target machine. Other important sub-projects include the Opcode Database, shellcode archive and related research. The Metasploit Project
Metasploit
Protocol
assigned by the program that generates any kind of query. QR - Query/Response. OPCODE - A 4-bit field that specifies the kind of query in this message. This value
Link-Local Multicast Name Resolution
Link-Local_Multicast_Name_Resolution
Basic instruction cycle in a computer
operations based on specific opcodes in the instruction. For example, in RISC-V architecture, funct3 and funct7 opcodes exist to distinguish whether an
Instruction_cycle
Machine instruction that indicates to a computer to do nothing
effects; for example, on the Motorola 68000 series of processors, the NOP opcode causes a synchronization of the pipeline. Listed below are the NOP instruction
NOP_(code)
Processor executing one instruction in minimal clock cycles
conclusions worked in concert; removing instructions would allow the instruction opcodes to be shorter, freeing up bits in the instruction word which could then
Reduced instruction set computer
Reduced_instruction_set_computer
64-bit RISC instruction set architecture
It has a 6-bit opcode field, a 5-bit Ra field, a 5-bit Rb field and a 16-bit displacement field. Branch instructions have a 6-bit opcode field, a 5-bit
DEC_Alpha
8-bit microprocessor from 1975
instruction operation codes (opcodes) are 8 bits long and have the general form AAABBBCC, where AAA and CC define the opcode, and BBB defines the addressing
MOS_Technology_6502
Type of computer instructions
sign-extension and points out the potential is much greater. Intel BCD opcodes Power ISA has a large range of bit manipulation instructions, largely due
Bit_manipulation_instructions
8-bit microprocessor
registers. The binary opcodes (machine language) were identical, but preceded by a new opcode prefix. Zilog published the opcodes and related mnemonics
Zilog_Z80
Aspect of the instruction set architecture of CPUs
particular operand. Keeping the addressing mode specifier bits separate from the opcode operation bits produces an orthogonal instruction set. Even on a computer
Addressing_mode
Computer machine code instruction
design flaw was discovered by programmers. Due to incomplete opcode decoding, two illegal opcodes, 0x9D and 0xDD, will cause the program counter on the processor
Halt and Catch Fire (computing)
Halt_and_Catch_Fire_(computing)
Machine instruction executing another instruction repeatedly
repeat instructions (REP(∅/E/Z/NE/NZ)) which are called "repeat string opcode prefixes" and may only be applied to a small number of string instructions
Repeat_instruction
Microprocessor produced by Western Digital
ever produced. When a standard WD16 processor executes opcodes F500 to FFFF, the reserved opcode trap is taken, loading PC from 001A. The high-order ten
WD16
Series of 16-bit computers by Texas Instruments
of program SVC DATA >0000 R3 - Open I/O opcode DATA >0B00 R4 - Write I/O opcode DATA >0100 R5 - Close I/O opcode DATA STRING R6 - Message address DATA STRLEN
TI-990
Instruction set architecture
(immediate), and J (jump). Every instruction starts with a 6-bit opcode. In addition to the opcode, R-type instructions specify three registers, a shift amount
MIPS_architecture
Communications protocol for lighting control
the same on all Art-Net packets, while the green portion is variable. The opcode (given in little endian) tells the recipient this is a packet containing
Art-Net
Instruction for x86 processors
flags are set to 0, while AF flag is undefined. There are 9 different opcodes for the TEST instruction depending on the type and size of the operands
TEST_(x86_instruction)
Model that describes the programmable interface of a computer processor
instructions. On the processing architecture, a given instruction may specify: opcode (the instruction to be performed) e.g. add, copy, test any explicit operands:
Instruction_set_architecture
Instruction set architecture developed by Digital Equipment Corporation
as defined above. This group of instructions takes up 75% of available opcodes. The ADD and SUB instructions use word addressing, and have no byte-oriented
PDP-11_architecture
8-bit microcontroller product lines from STMicroelectronics
addressing modes (X) and (Y). The instruction set consists of one byte of opcode, followed by up to two one-byte operands. The instruction set can be summarized
ST6_and_ST7
Assembly languages for the RISC-V computer architecture
with one or more operands to translate into one or more bytes known as an opcode. RISC-V processors feature a set of registers that serve as storage for
RISC-V_assembly_language
has a single opcode. In others, some instructions have an opcode and one or more modifiers. E.g., on the IBM System/370, byte 0 is the opcode but when byte
Comparison of instruction set architectures
Comparison_of_instruction_set_architectures
Instruction set architecture extension for microprocessors
high-order bits set to four, which replaces sixteen opcodes numbered 0x40–0x4F. Previously, those opcodes were individual INC and DEC instructions for the
REX_prefix
64-bit x86 register
In x86-64 mode, RDTSC also clears the upper 32 bits of RAX and RDX. Its opcode is 0F 31. Pentium competitors such as the Cyrix 6x86 did not always have
Time_Stamp_Counter
Electronic test instrument that measures multiple signals from a circuit
timing diagrams, protocol decodes, state machine traces, opcodes, or may correlate opcodes with source-level software. Logic analyzers have advanced
Logic_analyzer
Instruction in computer program
Machine code General concepts Instruction set Opcode Illegal opcode Opcode table Opcode prefix Operand Addressing mode Instructions NOP Branch Indirect
Branch_(computer_science)
Family of backward-compatible assembly languages
human-readable compared to raw machine code. Each machine code instruction is an opcode which, in assembly, is replaced with a mnemonic. Each mnemonic corresponds
X86_assembly_language
Esoteric programming language
carriage returns. The language uses 10 opcodes and each word in the source code is translated into an opcode by adding all the digits in the word together
Leet_(programming_language)
8-bit microcontroller family
rarely used branch instructions have had their opcodes changed to require a 90 prefix, and the unprefixed opcodes reassigned to signed branches which depend
STM8
of JMP (opcodes E9 and FF /4), CALL (opcodes E8 and FF /2), RET (opcodes C2 and C3), and the short/near forms of the Jcc instructions (opcodes 70..7F and
List of discontinued x86 instructions
List_of_discontinued_x86_instructions
performed by these opcodes is the same for Intel and AMD. This documentation difference applies only to the MMX/SSE forms of these opcodes — for VEX/EVEX-encoded
List_of_x86_SIMD_instructions
Instruction for x86 microprocessors
In the x86 architecture, the CPUID instruction (identified by a CPUID opcode) is a processor supplementary instruction (its name derived from "CPU Identification")
CPUID
Anomaly in computer security and programming
The Metasploit Project, for example, maintains a database of suitable opcodes, though it lists only those found in the Windows operating system. A buffer
Buffer_overflow
Assembly language and bytecode for web browsers
concatenation of the SIMD prefix, plus an opcode that is valid after the SIMD prefix, forms each SIMD opcode. The SIMD opcodes bring an additional 236 instructions
WebAssembly
Data transfer protocol designed for mobile devices
Opcode Operation Name Explanation 0x9805 GetObjectPropList Metadata transfer 0x9806 SetObjectPropList 0x1019 MoveObject Rename a file or directory 0x101B
Media_Transfer_Protocol
Computer network protocol
request or response header containing an opcode that determines the associated operation, any relevant opcode-specific information (such as which ports
Port_Control_Protocol
Comprehensive list of features of x86-based computers
structures, CMOS settings, memory and port addresses, as well as processor opcodes for x86 machines from the 1981 IBM PC up to 2000 (including many clones)
Ralf_Brown's_Interrupt_List
System to identify resources on a network
follows: QR: 1 bit Indicates if the message is a query (0) or a reply (1). OPCODE: 4 bits The type can be QUERY (standard query, 0), IQUERY (inverse query
Domain_Name_System
Abstract machine that uses only one instruction
that uses only one instruction – obviating the need for a machine language opcode. With a judicious choice for the single instruction and given arbitrarily
One-instruction_set_computer
Computer instruction executing another instruction
Machine code General concepts Instruction set Opcode Illegal opcode Opcode table Opcode prefix Operand Addressing mode Instructions NOP Branch Indirect
Execute_instruction
Programming language with hardware abstraction
if any, language elements that translate directly to a machine's native opcodes. Other features, such as string handling, object-oriented programming features
High-level programming language
High-level_programming_language
8-bit microprocessor
the regular encoding of the MOV instruction (using a quarter of available opcode space), there are redundant codes to copy a register into itself (MOV B
Intel_8080
CLASS { &opcode INTEGER UNIQUE, &InvocationParsType, &ResponseParsAndResultType, &ExceptionList ERROR OPTIONAL } WITH SYNTAX { OPCODE &opcode REQUEST ARGUMENTS
Information Object Class (ASN.1)
Information_Object_Class_(ASN.1)
Type of random-access memory
Description Bit Description ↓ RQ11 0 0 COL opcode 0 COLX opcode 0 ROWP opcode 0 ROWA opcode 1 COLM opcode ↓ RQ10 0 0 0 0 1 M3 Write mask low bits ↓ RQ9
XDR_DRAM
Type of computer memory
CID0–2 H V Column C3–10 V AP V CID3 Vref CA L H H L L L Opcode OP0-6 L V Vref CS L H H L L L Opcode OP0-6 H V Refresh management L H H L L H CID3 Bank V
DDR5_SDRAM
Graphics file format
version 2. This version featured 16-bit opcodes and numerous changes which enhanced its utility. PICT 1 opcodes were supported as a subset for backward
PICT
CPU register that is always zero
benefit on performance. Some architectures accomplish this with dedicated opcodes, specialized variations of their basic instructions. Implementing these
Zero_register
Unconditional jump instruction in x86 assembly language
execution by changing the program counter. There are a number of different opcodes that perform a jump; depending on whether the processor is in real mode
JMP_(x86_instruction)
Design flaw in 1993-1997 Intel processors
compare and exchange of 8 bytes in register EAX). The bug also applies to opcodes ending in C9 through CF, which specify register operands other than EAX
Pentium_F00F_bug
Central processing unit
the undocumented Z80 instructions were made official, including all the opcodes for instructions dealing with IX and IY as 8-bit registers (IXH, IXL, IYH
R800
Macintosh multimedia software
Open Music System (OMS) was a virtual studio management application by Opcode for the Classic Mac OS. Similar to FreeMIDI by Mark of the Unicorn and Audio
Open_Music_System
Digital circuit
prediction by using 4 semantically equivalent branch opcodes to represent each branch operator type. The opcode used indicated the history of that particular
Branch_predictor
Process virtual machine developed by Meta
Zend Engine transforms PHP source code into opcodes that serve as a form of bytecode, and executes the opcodes directly on the Zend Engine's virtual CPU
HHVM
Open-source CPU instruction set architecture
compensate, RISC-V's 32-bit instructions are actually 30 bits; 3⁄4 of the opcode space is reserved for an optional (but recommended) variable-length compressed
RISC-V
Instruction set architecture extension for microprocessors
previously existing instruction codes. This serves the following purposes: The opcode map is extended to make space for future instructions. It allows instruction
VEX_prefix
Instruction for x86 processors
FCMOV is a floating point conditional move opcode of the Intel x86 architecture, first introduced in Pentium Pro processors. It copies the contents of
FCMOV
1964 British computer specification
format: FF [Q] nnn m FF, the "order number", was the numerical instruction opcode. Q indicated the query function, and nnn and m were three-digit and one-digit
City_&_Guilds_Mnemonic_Code
1960s decimal computer
201–332. The 1401's instruction format is Opcode with [A-or-I-or-unit-address [B-address]] [modifier] word mark Opcodes are one character. Memory addresses
IBM_1401
CMOS microprocessor in the 6502 family
addressing modes, produce a total of 151 opcodes of the possible 256 8-bit opcode patterns. The remaining 105 unused opcodes are undefined, with the set of codes
WDC_65C02
Free and open-source virtual private network software
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 0 0 Opcode KeyID Session ID 4 32 Session ID 8 64 Session ID HMAC 12 96 HMAC ⋮ ⋮ 24
OpenVPN
Feature of HDMI
is acknowledged, the device tries another address. The second byte is an opcode which specifies the operation to be performed, and the number and meaning
Consumer_Electronics_Control
8-bit microprocessor
were based on the same core as the 6502, and are opcode compatible, including undocumented opcodes. The parallel port was provided by using several formerly
MOS_Technology_6510
Visual programming language
Max Software and Ben Austin moved to Opcode Systems, which became the publisher of record for Max. Although Opcode launched its commercial version named
Max_(programming_language)
Type of computer
code (sometimes called p-code), instructions will frequently have only an opcode commanding an operation, with no additional fields identifying a constant
Stack_machine
Instruction encoding rule for the x86 instruction set
set. 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
ModR/M
Family of instruction set architectures
encoding space, most registers are expressed in opcodes using three or four bits, the latter via an opcode prefix in 64-bit mode, while at most one operand
X86
instructions in the instruction set of the Common Intermediate Language bytecode. Opcode abbreviated from operation code is the portion of a machine language instruction
List_of_CIL_instructions
Type of program control instruction
Machine code General concepts Instruction set Opcode Illegal opcode Opcode table Opcode prefix Operand Addressing mode Instructions NOP Branch Indirect
Indirect_branch
Mechanism that ensures threads are not executed in parallel
"""Execute bytecode.""" lock = Lock() for (opcode, args) in bytecode: lock.acquire() INSTRUCTION_TABLE[opcode](args) lock.release() Free-Threaded Build
Global_interpreter_lock
Software that executes source code directly
particular code segment is executed the interpreter simply loads or jumps to the opcode mapping in the template and directly runs it on the hardware. Due to its
Interpreter_(computing)
Computer programmer
but a 1 was carried into the bits from which the opcode would be read—in this case changing the opcode to "jump to" so that the full instruction became
The_Story_of_Mel
CPU architecture
microprocessor, with a very small number of basic operations and corresponding opcodes, together forming an instruction set. Such sets are commonly stack-based
Minimal instruction set computer
Minimal_instruction_set_computer
Serial bus connecting MAC devices with the Ethernet physical layer
always contains the combination '01'. OP The Opcode consists of 2 bits. There are two possible opcodes, read '10' or write '01'. PA5 5 bits, PHY address
Management_Data_Input/Output
1984 video game
Opcode Mnemonic Argument(s) Action 0 DAT B A non-executable instruction used to store the data value B. 1 MOV A, B Move the contents of A to location B
Core_War
8-bit microprocessor
Instructions are one to three bytes long. The instruction format is an opcode byte, followed by up to two bytes of operands. Operands can be an address
Intel_8008
Mainframe computer, 1960s
the IBM 709: A three-bit opcode (prefix), 15-bit decrement (D), three-bit tag (T), and 15-bit address (Y) A twelve-bit opcode, two-bit flag (F), four unused
IBM_7090
Topics referred to by the same term
a security framework ASCII adjust after addition, one of the Intel BCD opcodes for working with binary-coded decimal on x86 .aaa, the American Automobile
AAA
Olivetti programmable calculator launched in 1964
Instruction Opcode Operation Sum + A = A + Chosen Register (hereinafter "CR") Subtraction - A = A - CR Multiplication x A = A * CR Division : A = A : CR
Programma_101
Central computer component that executes instructions
combination of bits, known as the machine language opcode. While processing an instruction, the CPU decodes the opcode (via a binary decoder) into control signals
Central_processing_unit
Type of simple executable file
works on all three processors.) C9h is an invalid opcode on the 8088/8086, however it is the opcode for LEAVE since the 80188/80186. Albeit possible,
COM_file
8-bit microprocessor
Z80 clocked at 150 MHz if fast memory is used (i.e. no wait states for opcode fetches, for data, or for I/O) or even higher in some applications (a 16-bit
Zilog_eZ80
64-bit extension of x86 architecture
Intel 64. The 0F 0D /r opcode with the ModR/M byte's Mod field set to 11b is a Reserved-NOP on Intel 64 but will cause #UD (invalid-opcode exception) on AMD64
X86-64
travel, tourism, insurance
OPCODE
OPCODE
OPCODE
OPCODE
OPCODE
OPCODE
OPCODE
OPCODE
OPCODE
travel, tourism, insurance