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<title>Opcode</title>

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Opcode

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</style><table class="sidebar nomobile nowraplinks" style="margin-top: 0.5em;"><tbody><tr><th class="sidebar-title" style="background-color: rgba(51, 153, 255, 0.15); color: inherit;"><a href="Machine_code" title="Machine code">Machine code</a></th></tr><tr><th class="sidebar-heading" style="background-color: rgba(51, 153, 255, 0.15); color: inherit;">

General concepts</th></tr><tr><td class="sidebar-content" style="text-align: left;">

<ul><li><a href="Instruction_set_architecture" title="Instruction set architecture">Instruction set</a></li>

<li>

<ul><li><a href="Illegal_opcode" title="Illegal opcode">Illegal opcode</a></li>

<li><a href="Opcode_table" title="Opcode table">Opcode table</a></li>

<li><a href="Opcode_prefix" title="Opcode prefix">Opcode prefix</a></li></ul></li>

<li><a href="Operand#Computer_science" title="Operand">Operand</a></li></ul></td>

</tr><tr><th class="sidebar-heading" style="background-color: rgba(51, 153, 255, 0.15); color: inherit;">

Instructions</th></tr><tr><td class="sidebar-content" style="text-align: left;">

<li><a href="Branch_(computer_science)" title="Branch (computer science)">Branch</a>

<ul><li><a href="Indirect_branch" title="Indirect branch">Indirect branch</a></li></ul></li>

<li><a href="Repeat_instruction" title="Repeat instruction">Repeat instruction</a></li>

<li><a href="Execute_instruction" title="Execute instruction">Execute instruction</a></li></ul></td>

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In <a href="Computing" title="Computing">computing</a>, an opcode (abbreviated from operation code)<a href="#cite_note-Barron_1978_Opcode-1">[1]</a><a href="#cite_note-Chiba_2007-2">[2]</a> is an <a href="Enumeration" title="Enumeration">enumerated value</a> that specifies the operation to be performed. Opcodes are employed in hardware devices such as <a href="Arithmetic_logic_unit" title="Arithmetic logic unit">arithmetic logic units</a> (ALUs), <a href="Central_processing_units" class="mw-redirect" title="Central processing units">central processing units</a> (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 <a href="Machine_code" title="Machine code">machine language</a> <a href="Instruction_(computer_science)" class="mw-redirect" title="Instruction (computer science)">instruction</a> that specifies the operation to be performed.

Opcodes are found in the machine language instructions of CPUs as well as in some <a href="Virtual_machine#Process_virtual_machines" title="Virtual machine">abstract computing machines</a>. In CPUs, an opcode may be referred to as an instruction machine code,<a href="#cite_note-Intel_1973_MCS-4-3">[3]</a> instruction code,<a href="#cite_note-Intel_1974_MCS-40-4">[4]</a> instruction syllable,<a href="#cite_note-Jones_1988_CISC-5">[5]</a><a href="#cite_note-Domagała_2012-6">[6]</a><a href="#cite_note-Smotherman_2013-7">[7]</a><a href="#cite_note-Jones_2016_CISC-8">[8]</a> instruction parcel, or opstring.<a href="#cite_note-Schulman_2005-9">[9]</a><a href="#cite_note-Chiba_2007-2">[2]</a> For any particular processor (which may be a general CPU or a more specialized processing unit), the opcodes are defined by the processor's <a href="Instruction_set_architecture" title="Instruction set architecture">instruction set architecture</a> (ISA).<a href="#cite_note-Hennessy_2017-10">[10]</a> They can be described using an <a href="Opcode_table" title="Opcode table">opcode table</a>. The types of operations may include <a href="Arithmetic" title="Arithmetic">arithmetic</a>, data copying, <a href="Logical_operation" class="mw-redirect" title="Logical operation">logical operations</a>, program control, and special instructions (e.g., <a href="CPUID" title="CPUID">CPUID</a>).<a href="#cite_note-Hennessy_2017-10">[10]</a>

In addition to the opcode, many instructions specify the data (known as <a href="Operand" title="Operand">operands</a>) the operation will act upon, although some instructions may have implicit operands or none.<a href="#cite_note-Hennessy_2017-10">[10]</a> Some instruction sets have nearly uniform fields for opcode and operand specifiers, whereas others (e.g., <a href="X86" title="X86">x86</a> architecture) have a less uniform, variable-length structure.<a href="#cite_note-Hennessy_2017-10">[10]</a><a href="#cite_note-Mansfield_1983-11">[11]</a> Instruction sets can be extended through <a href="Opcode_prefix" title="Opcode prefix">opcode prefixes</a>, which add a subset of new instructions made up of existing opcodes following reserved byte sequences.

<div class="mw-heading mw-heading3"><h3 id="Sample_opcode_table">Sample opcode table</h3></div>

This table shows opcodes of a simple 8-bit microprocessor, the <a href="Intel_8008" title="Intel 8008">Intel 8008</a> from 1972.

Each opcode is 8 <a href="Bit" title="Bit">bits</a> long. Each is shown as a <a href="Binary_number" title="Binary number">binary</a> pattern of ones and zeros in the Opcode column. Up to two additional fields may be embedded into the opcode. Some 3-bit fields are labeled DDD, SSS, CC, and ALU. The SSS (source) and DDD (destination) fields specify one of the eight possible 8008 <a href="Processor_register" title="Processor register">registers</a> or memory: A, B, C, D, E, H, L, or M. CC specifies a condition that will activate certain JMP, CAL, and RET instructions. ALU specifies one of a possible eight <a href="Arithmetic_logic_unit" title="Arithmetic logic unit">arithmetic logic unit</a> functions to be performed during an instruction, specifically, add, add with carry, subtract, subtract with borrow, logical AND, logical XOR, logical OR, and compare. The X in some fields means that either a 1 or 0 can be inserted with <a href="Don't-care_term" title="Don't-care term">no effect</a>.

The fixed ones and zeros are combined with the parameter fields to build the 8-bit opcode. Additionally, the full instruction might require one or two additional bytes of operands. These are shown in the second major column of the table, labeled Operands. If no operands are required, the column is filled with a dash (—).

Since the ones and zeros are difficult to remember, the Mnemonic column shows a short, easy to remember letter code that an <a href="Assembly_language" title="Assembly language">assembly language</a> programmer may use to invoke the required opcode.

The Description column shows the function performed by the microprocessor when it encounters a specific opcode.

<th colspan="8">Opcode</th>

<th colspan="2">Operands</th>

<th rowspan="2">Mnemonic</th>

<th rowspan="2">Description

</th></tr>

<tr>

<th>b3

</th></tr>

<tr>

<td align="left">Halt

</td></tr>

<tr>

<td align="left">DDD ← DDD + 1 (except A and M)

</td></tr>

<tr>

<td align="left">DDD ← DDD - 1 (except A and M)

</td></tr>

<tr>

<td align="left">A1-7 ← A0-6; A0 ← Cy ← A7

</td></tr>

<tr>

<td align="left">Rcc (RET conditional)</td>

<td align="left">If cc true, P ← (stack)

</td></tr>

<tr>

<td align="left">A ← A [ALU operation] data

</td></tr>

<tr>

<td align="left">(stack) ← P, P ← N x 8

</td></tr>

<tr>

<td align="left">LrI data (Load r with immediate data)</td>

<td align="left">DDD ← data

</td></tr>

<tr>

<td align="left">P ← (stack)

</td></tr>

<tr>

<td align="left">A0-6 ← A1-7; A7 ← Cy ← A0

</td></tr>

<tr>

<td align="left">A1-7 ← A0-6; Cy ← A7; A0 ← Cy

</td></tr>

<tr>

<td align="left">A0-6 ← A1-7; Cy ← A0; A7 ← Cy

</td></tr>

<tr>

<td>addlo</td>

<td>addhi</td>

<td align="left">Jcc add (JMP conditional)</td>

<td align="left">If cc true, P ← add

</td></tr>

<tr>

<td align="left">A ← Port (ports 0-7 only)

</td></tr>

<tr>

<td align="left">Port ← A (ports 8-31 only)

</td></tr>

<tr>

<td>addlo</td>

<td>addhi</td>

<td align="left">Ccc add (CAL conditional)</td>

<td align="left">If cc true, (stack) ← P, P ← add

</td></tr>

<tr>

<td>addlo</td>

<td>addhi</td>

<td align="left">P ← add

</td></tr>

<tr>

<td>addlo</td>

<td>addhi</td>

<td align="left">(stack) ← P, P ← add

</td></tr>

<tr>

<td align="left">A ← A [ALU operation] SSS

</td></tr>

<tr>

<td align="left">DDD ← SSS

</td></tr>

<tr>

<td align="left">Halt

</td></tr>

<tr>

<th>Mnemonic</th>

<th>Description

</th></tr>

<tr>

</th></tr>

<tr>

<th>ALU

</th></tr>

<tr>

<td colspan="2">FC, C false</td>

<td align="left">ADr ADI (A ← A + arg)

</td></tr>

<tr>

<td colspan="2">FZ, Z false</td>

<td align="left">ACr ACI (A ← A + arg + Cy)

</td></tr>

<tr>

<td colspan="2">FS, S false</td>

<td align="left">SUr SUI (A ← A - arg)

</td></tr>

<tr>

<td align="left">SBr SBI (A ← A - arg - Cy)

</td></tr>

<tr>

<td align="left">NDr NDI (A ← A ∧ arg)

</td></tr>

<tr>

<td align="left">XRr XRI (A ← A ⊻ arg)

</td></tr>

<tr>

<td align="left">ORr ORI (A ← A ∨ arg)

</td></tr>

<tr>

<td align="left">CPr CPI (A - arg)

</td></tr>

<tr>

<th>ALU

</th></tr></tbody></table>

<div class="mw-heading mw-heading2"><h2 id="Software_instruction_sets">Software instruction sets</h2></div>

Opcodes can be found in <a href="Bytecode" title="Bytecode">bytecodes</a> and other representations intended for execution by software interpreters. These often employ slightly higher-level data types and operations than those found in hardware opcodes but are nevertheless constructed along similar lines. Examples include the byte code found in <a href="Java_class_file" title="Java class file">Java class files</a>, which are interpreted by <a href="Java_virtual_machine" title="Java virtual machine">Java virtual machines</a>, the byte code used in <a href="GNU_Emacs" title="GNU Emacs">GNU Emacs</a> for compiled <a href="Lisp_(programming_language)" title="Lisp (programming language)">Lisp</a> code, and NET <a href="Common_Intermediate_Language" title="Common Intermediate Language">Common Intermediate Language</a>.<a href="#cite_note-bytecode-12">[12]</a>

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<ul><li><a href="Gadget_(machine_instruction_sequence)" class="mw-redirect" title="Gadget (machine instruction sequence)">Gadget (machine instruction sequence)</a></li>

<li><a href="Illegal_opcode" title="Illegal opcode">Illegal opcode</a></li>

<li><a href="Syllable_(computing)" title="Syllable (computing)">Syllable (computing)</a></li>

<li><a href="Fused_operation" class="mw-redirect" title="Fused operation">Fused operation</a></li></ul>

<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

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</style><cite id="CITEREFBarron1978" class="citation book cs1 cs1-prop-location-test"><a href="David_W._Barron" title="David W. Barron">Barron, David William</a> (1978) [1971, 1969]. "2.1. Symbolic instructions". Written at <a href="University_of_Southampton" title="University of Southampton">University of Southampton</a>, Southampton, UK. In Floretin, J. John (ed.). Assemblers and Loaders. Computer Monographs (3 ed.). New York, USA: <a href="Elsevier_North-Holland_Inc." class="mw-redirect" title="Elsevier North-Holland Inc.">Elsevier North-Holland Inc.</a> p. 7. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>0-444-19462-2</bdi>. <a href="LCCN_(identifier)" class="mw-redirect" title="LCCN (identifier)">LCCN</a> <a rel="nofollow" class="external text" href="https://lccn.loc.gov/78-19961">78-19961</a>.</cite> (xii+100 pages)

</li>

<li id="cite_note-Chiba_2007-2">^ <a href="#cite_ref-Chiba_2007_2-0">a</a> <a href="#cite_ref-Chiba_2007_2-1">b</a> <cite id="CITEREFChiba2007" class="citation web cs1">Chiba, Shigeru (2007) [1999]. <a rel="nofollow" class="external text" href="http://www.docjar.org/html/api/javassist/bytecode/InstructionPrinter.java.html">"Javassist, a Java-bytecode translator toolkit"</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200302185725/http://www.docjar.org/html/api/javassist/bytecode/InstructionPrinter.java.html">Archived</a> from the original on 2020-03-02. Retrieved 2016-05-27.</cite>

</li>

<li id="cite_note-Intel_1973_MCS-4-3"><a href="#cite_ref-Intel_1973_MCS-4_3-0">^</a> <cite class="citation book cs1"><a rel="nofollow" class="external text" href="http://bitsavers.trailing-edge.com/components/intel/MCS4/MCS-4_Assembly_Language_Programming_Manual_Dec73.pdf">"Appendix B - Instruction Machine Codes"</a> (PDF). MCS-4 Assembly Language Programming Manual - The INTELLEC 4 Microcomputer System Programming Manual (Preliminary ed.). Santa Clara, California, USA: <a href="Intel_Corporation" class="mw-redirect" title="Intel Corporation">Intel Corporation</a>. December 1973. pp. B-1 – B-8. MCS-030-1273-1. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200301235541/http://bitsavers.trailing-edge.com/components/intel/MCS4/MCS-4_Assembly_Language_Programming_Manual_Dec73.pdf">Archived</a> (PDF) from the original on 2020-03-01. Retrieved 2020-03-02.</cite>

</li>

<li id="cite_note-Intel_1974_MCS-40-4"><a href="#cite_ref-Intel_1974_MCS-40_4-0">^</a> <cite id="CITEREFRaphael1974" class="citation book cs1">Raphael, Howard A., ed. (November 1974). <a rel="nofollow" class="external text" href="http://bitsavers.trailing-edge.com/components/intel/MCS40/MCS-40_Users_Manual_Nov74.pdf">"The Functions Of A Computer: Instruction Register And Decoder"</a> (PDF). MCS-40 User's Manual For Logic Designers. Santa Clara, California, USA: <a href="Intel_Corporation" class="mw-redirect" title="Intel Corporation">Intel Corporation</a>. p. viii. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200303024244/http://bitsavers.trailing-edge.com/components/intel/MCS40/MCS-40_Users_Manual_Nov74.pdf">Archived</a> (PDF) from the original on 2020-03-03. Retrieved 2020-03-03. <q>[…] Each operation that the processor can perform is identified by a unique binary number known as an instruction code. […]</q></cite>

</li>

<li id="cite_note-Jones_1988_CISC-5"><a href="#cite_ref-Jones_1988_CISC_5-0">^</a> <cite id="CITEREFJones1988" class="citation journal cs1">Jones, Douglas W. (June 1988). <a rel="nofollow" class="external text" href="https://doi.org/10.1145%2F48675.48684">"A Minimal CISC"</a>. ACM SIGARCH Computer Architecture News. 16 (3). New York, USA: <a href="Association_for_Computing_Machinery" title="Association for Computing Machinery">Association for Computing Machinery</a> (ACM): 56–63. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1145%2F48675.48684">10.1145/48675.48684</a>. <a href="S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:17280173">17280173</a>.</cite>

</li>

<li id="cite_note-Domagała_2012-6"><a href="#cite_ref-Domagała_2012_6-0">^</a> <cite id="CITEREFDomagała2012" class="citation book cs1">Domagała, Łukasz (2012). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=e6apNOED26kC">"7.1.4. Benchmark suite"</a>. <a rel="nofollow" class="external text" href="https://books.google.com/books?id=e6apNOED26kC">Application of CLP to instruction modulo scheduling for VLIW processors</a>. Gliwice, Poland: Jacek Skalmierski Computer Studio. pp. 80–83 [83]. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-83-62652-42-6</bdi>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200302192452/https://books.google.de/books?hl=de&id=e6apNOED26kC&jtp=83">Archived</a> from the original on 2020-03-02. Retrieved 2016-05-28.</cite>

</li>

<li id="cite_note-Smotherman_2013-7"><a href="#cite_ref-Smotherman_2013_7-0">^</a> <cite id="CITEREFSmotherman2016" class="citation web cs1">Smotherman, Mark (2016) [2013]. <a rel="nofollow" class="external text" href="https://people.cs.clemson.edu/~mark/330/ilp.txt">"Multiple Instruction Issue"</a>. School of Computing, Clemson University. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20160528142545/https://people.cs.clemson.edu/~mark/330/ilp.txt">Archived</a> from the original on 2016-05-28. Retrieved 2016-05-28.</cite>

</li>

<li id="cite_note-Jones_2016_CISC-8"><a href="#cite_ref-Jones_2016_CISC_8-0">^</a> <cite id="CITEREFJones2016" class="citation web cs1">Jones, Douglas W. (2016) [2012]. <a rel="nofollow" class="external text" href="http://homepage.cs.uiowa.edu/~jones/arch/cisc/">"A Minimal CISC"</a>. Computer Architecture On-Line Collection. Iowa City, USA: <a href="The_University_of_Iowa" class="mw-redirect" title="The University of Iowa">The University of Iowa</a>, Department of Computer Science. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200302190911/http://homepage.cs.uiowa.edu/~jones/arch/cisc/">Archived</a> from the original on 2020-03-02. Retrieved 2016-05-28.</cite>

</li>

<li id="cite_note-Schulman_2005-9"><a href="#cite_ref-Schulman_2005_9-0">^</a> <cite id="CITEREFSchulman2005" class="citation magazine cs1">Schulman, Andrew (2005-07-01). <a rel="nofollow" class="external text" href="http://www.drdobbs.com/finding-binary-clones-with-opstrings-fu/184406152">"Finding Binary Clones with Opstrings & Function Digests"</a>. <a href="Dr._Dobb's_Journal" title="Dr. Dobb's Journal">Dr. Dobb's Journal</a>. Part I. Vol. 30, no. 7. <a href="CMP_Media_LLC" class="mw-redirect" title="CMP Media LLC">CMP Media LLC</a>. pp. 69–73. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1044-789X">1044-789X</a>. #374. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200302175401/https://www.drdobbs.com/finding-binary-clones-with-opstrings-fu/184406152">Archived</a> from the original on 2020-03-02. Retrieved 2020-03-02</cite>; <cite id="CITEREFSchulman2005" class="citation magazine cs1">Schulman, Andrew (2005-08-01). <a rel="nofollow" class="external text" href="http://www.drdobbs.com/finding-binary-clones-with-opstrings-fu/184406203">"Finding Binary Clones with Opstrings & Function Digests"</a>. <a href="Dr._Dobb's_Journal" title="Dr. Dobb's Journal">Dr. Dobb's Journal</a>. Part II. Vol. 30, no. 8. <a href="CMP_Media_LLC" class="mw-redirect" title="CMP Media LLC">CMP Media LLC</a>. pp. 56–61. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1044-789X">1044-789X</a>. #375. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200302185255/https://www.drdobbs.com/finding-binary-clones-with-opstrings-fu/184406203">Archived</a> from the original on 2020-03-02. Retrieved 2016-05-28</cite>; <cite id="CITEREFSchulman2005" class="citation magazine cs1">Schulman, Andrew (2005-09-01). <a rel="nofollow" class="external text" href="http://www.drdobbs.com/tools/finding-binary-clones-with-opstrings-fu/184406247">"Finding Binary Clones with Opstrings & Function Digests"</a>. <a href="CMP_Media_LLC" class="mw-redirect" title="CMP Media LLC">CMP Media LLC</a>. Part III. Vol. 30, no. 9. <a href="United_Business_Media" class="mw-redirect" title="United Business Media">United Business Media</a>. pp. 64–70. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1044-789X">1044-789X</a>. #376. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200302185646/https://www.drdobbs.com/tools/finding-binary-clones-with-opstrings-fu/184406247?pgno=3">Archived</a> from the original on 2020-03-02. Retrieved 2016-05-28.</cite>

</li>

<li id="cite_note-Hennessy_2017-10">^ <a href="#cite_ref-Hennessy_2017_10-0">a</a> <a href="#cite_ref-Hennessy_2017_10-1">b</a> <a href="#cite_ref-Hennessy_2017_10-2">c</a> <a href="#cite_ref-Hennessy_2017_10-3">d</a> <cite id="CITEREFHennessyPattersonAsanovićBakos2017" class="citation book cs1">Hennessy, John L.; Patterson, David A.; <a href="Krste_Asanovi%C4%87" title="Krste Asanović">Asanović, Krste</a>; Bakos, Jason D.; Colwell, Robert P.; Bhattacharjee, Abhishek; Conte, Thomas M.; Duato, José; Franklin, Diana; Goldberg, David; Jouppi, Norman P.; Li, Sheng; Muralimanohar, Naveen; Peterson, Gregory D.; Pinkston, Timothy M.; Ranganathan, Parthasarathy; Wood, David A.; Young, Cliff; Zaky, Amr (2017-11-23). Computer architecture: A quantitative approach (6 ed.). Cambridge, Massachusetts, USA: <a href="Morgan_Kaufmann_Publishers" title="Morgan Kaufmann Publishers">Morgan Kaufmann Publishers</a>. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-0-12811905-1</bdi>. <a href="OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/983459758">983459758</a>.</cite>

</li>

<li id="cite_note-Mansfield_1983-11"><a href="#cite_ref-Mansfield_1983_11-0">^</a> <cite id="CITEREFMansfield1983" class="citation book cs1">Mansfield, Richard (1983). <a rel="nofollow" class="external text" href="http://www.atariarchives.org/mlb/introduction.php">"Introduction: Why Machine Language?"</a>. <a rel="nofollow" class="external text" href="https://www.atariarchives.org/mlb/index.php">Machine Language For Beginners</a>. <a href="Compute!_Books" class="mw-redirect" title="Compute! Books">Compute! Books</a> (1 ed.). Greensboro, North Carolina, USA: <a href="COMPUTE!_Publications%2C_Inc." class="mw-redirect" title="COMPUTE! Publications, Inc.">COMPUTE! Publications, Inc.</a>, <a href="American_Broadcasting_Companies%2C_Inc." class="mw-redirect" title="American Broadcasting Companies, Inc.">American Broadcasting Companies, Inc.</a>; <a href="Small_System_Services%2C_Inc." class="mw-redirect" title="Small System Services, Inc.">Small System Services, Inc.</a> <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>0-942386-11-6</bdi>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20080213090055/http://www.atariarchives.org/mlb/introduction.php">Archived</a> from the original on 2008-02-13. Retrieved 2016-05-28.</cite>

</li>

<li id="cite_note-bytecode-12"><a href="#cite_ref-bytecode_12-0">^</a> <cite class="citation magazine cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20121006015213/http://www.pcmag.com/encyclopedia_term/0%2C2542%2Ct%3Dbytecode%26i%3D39108%2C00.asp">"bytecode Definition"</a>. <a href="PC_Magazine" class="mw-redirect" title="PC Magazine">PC Magazine</a>. PC Magazine Encyclopedia. Archived from <a rel="nofollow" class="external text" href="https://www.pcmag.com/encyclopedia_term/0,2542,t=bytecode&i=39108,00.asp">the original</a> on 2012-10-06. Retrieved 2015-10-10.</cite>

</li>

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<ul><li><a href="Assembly_language" title="Assembly language">Assembly language</a></li>

<li><a href="Comparison_of_assemblers" title="Comparison of assemblers">Comparison of assemblers</a></li>

<li><a href="Disassembler" title="Disassembler">Disassembler</a></li>

<li><a href="Instruction_set_architecture" title="Instruction set architecture">Instruction set</a></li>

<li><a href="Low-level_programming_language" title="Low-level programming language">Low-level programming language</a></li>

<li><a href="Machine_code" title="Machine code">Machine code</a></li>

<li><a href="Microassembler" title="Microassembler">Microassembler</a></li>

<li><a href="X86_assembly_language" title="X86 assembly language">x86 assembly language</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="Comparison_of_assemblers#x86_assemblers" title="Comparison of assemblers">Assemblers</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="FASM" title="FASM">Flat Assembler</a> (FASM)</li>

<li><a href="GNU_Assembler" title="GNU Assembler">GNU Assembler</a> (GAS)</li>

<li><a href="High_Level_Assembly" title="High Level Assembly">High Level Assembly</a> (HLA)</li>

<li><a href="Microsoft_Macro_Assembler" title="Microsoft Macro Assembler">Microsoft Macro Assembler</a> (MASM)</li>

<li><a href="Netwide_Assembler" title="Netwide Assembler">Netwide Assembler</a> (NASM)</li>

<li><a href="Turbo_Assembler" title="Turbo Assembler">Turbo Assembler</a> (TASM)</li>

<li><a href="Open_Watcom_Assembler" title="Open Watcom Assembler">Open Watcom Assembler</a> (WASM)</li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Programming issues</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Call_stack" title="Call stack">Call stack</a></li>

<li><a href="FLAGS_register" title="FLAGS register">Flags</a>

<ul><li><a href="Carry_flag" title="Carry flag">Carry flag</a></li>

<li><a href="Direction_flag" title="Direction flag">Direction flag</a></li>

<li><a href="Interrupt_flag" title="Interrupt flag">Interrupt flag</a></li>

<li><a href="Overflow_flag" title="Overflow flag">Overflow flag</a></li>

<li><a href="Memory_address" title="Memory address">Memory address</a></li>

<li><a href="Program_counter" title="Program counter">Program counter</a></li>

<li><a href="Processor_register" title="Processor register">Processor register</a></li>

<li><a href="X86_calling_conventions" title="X86 calling conventions">Calling conventions</a></li>

<li><a href="X86_instruction_listings" title="X86 instruction listings">Instruction listings</a></li>

<li><a href="X86#x86_registers" title="X86">Registers</a></li></ul>

</div></td></tr></tbody></table></div></div><div><div class="zim-footer">

This article is issued from <a class="external text" title="Last edited on 2025-07-15" href="https://en.wikipedia.org/wiki/?title=Opcode&oldid=1300697202">Wikipedia</a>. The text is available under <a class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en">Creative Commons Attribution-Share Alike 4.0</a> unless otherwise noted. Additional terms may apply for the media files.

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