CINXE.COM
SC/MP from FOLDOC
<!DOCTYPE html> <html lang="en"> <head> <title>SC/MP from FOLDOC</title> <meta http-equiv="Content-Security-Policy" content="default-src 'unsafe-inline' http: https:"> <meta name="verify-v1" content="siAI0ZOMn41hao0E/T76D1I2L3MtFjzE48P3ctCjRNU="> <meta charset="utf-8"> <meta name="viewport" content="width=device-width, initial-scale=1"> <meta name="msapplication-TileColor" content="#da532c"> <meta name="theme-color" content="#ffffff"> <meta name="google-translate-customization" content="828219db36930e1e-c51d915bf2ea717c-g9b503f9a85d5b5a7-a"> <!-- Google Analytics Global site tag (gtag.js) --> <script src="https://www.googletagmanager.com/gtag/js?id=UA-9715943-1"></script> <script> window.dataLayer = window.dataLayer || []; function gtag(){dataLayer.push(arguments);} gtag('js', new Date()); gtag('config', 'UA-9715943-1'); </script> <!-- End Google Analytics --> <link href="//fonts.googleapis.com/css?family=Duru+Sans%7CBelgrano%7CInconsolata%7CAlef%7CArmata" rel="stylesheet" type="text/css"> <link rel="stylesheet" type="text/css" href="/css/layout.css?2"> <!-- realfavicongenerator.net --> <link rel="apple-touch-icon" sizes="152x152" href="/im/apple-touch-icon.png"> <link rel="icon" type="image/png" sizes="32x32" href="/im/favicon-32x32.png"> <link rel="icon" type="image/png" sizes="16x16" href="/im/favicon-16x16.png"> <link rel="manifest" href="/im/site.webmanifest"> <link rel="mask-icon" href="/im/safari-pinned-tab.svg" color="#5bbad5"> <link rel="canonical" href="https://foldoc.org/SC/MP"> <link rel="alternate" type="application/rss+xml" title="FOLDOC" href="/rss.xml"> <link rel="search" title="FOLDOC" type="application/opensearchdescription+xml" href="//foldoc.org/search.xml"> <!-- AdSense --> <script async src="https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js?client=ca-pub-5521724329338202" crossorigin="anonymous"></script> <!-- AdSense end --> </head> <body> <div id="fb-root"></div> <script> (function (d, s, id) { var js, fjs = d.getElementsByTagName(s)[0]; if (d.getElementById(id)) return; js = d.createElement(s); js.id = id; js.src = "//connect.facebook.net/en_GB/all.js#xfbml=1"; fjs.parentNode.insertBefore(js, fjs); }(document, 'script', 'facebook-jssdk')); </script> <div id="container"> <div id="left"> <a href="/"> <img src="/foldoc.gif" width="300" height="98" alt="Free On-line Dictionary of Computing" class="logo"> </a> <div id="nav"> <a href="/contents.html" class="button">Contents</a> <a href="/help.html" class="button">Help</a> <a href="/random-entry" class="button">Random</a> </div> <form action="/"> <input type="text" name="query" id="query" autofocus="autofocus"> <input type="submit" name="action" value="Search" class="button"> </form> <div id="content"> <h2>SC/MP</h2> <p></p> <p><<i><a href="contents/processor.html">processor</a></i>></p> <p> (Nicknamed "Scamp") A typical 8-bit <a href="/microprocessor">microprocessor</a> from <a href="/National+Semiconductor">National Semiconductor</a> released in April 1976. It was intended for control applications (a simple <a href="/BASIC">BASIC</a> in a 2.5K <a href="/ROM">ROM</a> was added to one version). It featured 16 bit addressing, with 12 address lines and 4 lines borrowed from the data bus (it was common to borrow lines from the data bus for addressing). Internally, it included three <a href="/index+registers">index registers</a> (P1 to P3) and two 8-bit general-purpose <a href="/registers">registers</a>. It had a <a href="/PC">PC</a>, but no <a href="/stack+pointer">stack pointer</a> or <a href="/subroutine">subroutine</a> instructions (though they could be emulated with index registers). During <a href="/interrupts">interrupts</a>, the <a href="/PC">PC</a> was saved in P3. It was meant for embedded control, and these features were omitted for cost reasons. It was also <a href="/bit+serial">bit serial</a> internally to keep it cheap. <p></p> The unique feature was the ability to completely share a system bus with other processors. Most processors of the time assumed they were the only ones accessing memory or I/O devices. Multiple SC/MPs could be hooked up to the bus, as well as other intelligent devices, such as <a href="/DMA+controllers">DMA controllers</a>. A control line (ENOUT (Enable Out) to ENIN) could be chained along the processors to allow cooperative processing. This was very advanced for the time, compared to other <a href="/CPUs">CPUs</a>. <p></p> In addition to I/O ports like the <a href="/Intel+8080">Intel 8080</a>, the SC/MP also had instructions and one pin for serial input and one for output. <p></p> <p class="updated">Last updated: <a href="/new.html">1994-11-16</a></p> <p></p> <p class="vertical-space"></p><h3>Nearby terms:</h3> <p class="neighbours"> <a href="/Scientific+Data+Systems">Scientific Data Systems</a> ♦ <a href="/Sci-Hub">Sci-Hub</a> ♦ <a href="/SCL">SCL</a> ♦ <a href="/SCM">SCM</a> ♦ <b><a href="/SC/MP">SC/MP</a></b> ♦ <a href="/SCO">SCO</a> ♦ <a href="/Scode">Scode</a> ♦ <a href="/SCOOP">SCOOP</a> ♦ <a href="/SCOOPS">SCOOPS</a> </p> <p> Try this search on <a href="https://www.wikipedia.org/wiki/Special:Search?search=SC/MP">Wikipedia</a>, <a href="https://www.wiktionary.org/wiki/SC/MP">Wiktionary</a>, <a href="https://www.google.com/search?q=define:SC/MP">Google</a>, <a href="https://www.onelook.com/?w=SC/MP">OneLook</a>. </p> <p class="vertical-space"></p> <hr> <div></div> <hr> <!-- if HTMLCOMMENTBOX --> <div id="HCB_comment_box">Loading</div> <link rel="stylesheet" type="text/css" href="//www.htmlcommentbox.com/static/skins/bootstrap/twitter-bootstrap.css?v=0"> <script language="javascript" id="hcb"> hcb_user = { PAGE: 'https://foldoc.org/SC/MP', comments_header: ' ', no_comments_msg: ' ', err_comment_empty: 'Your comment was not posted because it was empty!', rss: '', }; var s = document.createElement("script"); s.setAttribute("type", "text/javascript"); s.setAttribute("src", "//www.htmlcommentbox.com/jread?page=" + escape(hcb_user.PAGE).replace(/\+/g, "%2B") + "&mod=%241%24wq1rdBcg%24.0y2uzvjA2bsnhzpXVq9F." + "&opts=17374&num=10"); // No e-mail field: 16846 if (typeof s != "undefined") document.getElementsByTagName("head")[0].appendChild(s); </script> <script> setTimeout(function () { document.getElementById('hcb_form_content').rows = 1 }, 1000); </script> <hr> <!-- end HTMLCOMMENTBOX --> </div> <!-- content --> </div> <!-- left --> <div id="right"> <div id="google_translate_element"> <script> function googleTranslateElementInit() { new google.translate.TranslateElement({ pageLanguage: 'en' }, 'google_translate_element'); } </script> <script src="https://translate.google.com/translate_a/element.js?cb=googleTranslateElementInit"></script> </div> <p><br></p> <hr> <div id="social"> <div class="fb-like" data-href="http://foldoc.org/" data-layout="button_count" data-action="like" data-show-faces="false" data-share="true"> </div> <a href="https://twitter.com/share" class="twitter-share-button" data-via="foldoc"> Tweet </a> <script> if (!document.getElementById('twitter-wjs')) { var fjs = document.getElementsByTagName('script')[0], js = document.createElement('script'); js.id = 'twitter-wjs'; js.src = 'https://platform.twitter.com/widgets.js'; fjs.parentNode.insertBefore(js, fjs); } </script> </div> <hr> <div> <p></p> </div> <p> <a href="/rss.xml"> <img src="/orangerss.gif" width="14" height="14" alt="RSS feed of new items"> </a> <a href="/new.html">Recent Updates</a> | <a href="/missing.html">Missing Terms</a> </p> <p>Updated: Tue, 11 Feb 2025 23:28:55 GMT</p> <p>15282 entries</p> <p><em><a href="/Free+On-line+Dictionary">Copyright Denis Howe 1985</a></em></p> </div> <!-- right --> </div> <!-- container --> <!-- Start Quantcast --> <script type="text/javascript"> window._qevents = window._qevents || []; (function() { var elem = document.createElement('script'); elem.src = 'https://secure.quantserve.com/quant.js'; elem.async = true; elem.type = 'text/javascript'; var scpt = document.getElementsByTagName('script')[0]; scpt.parentNode.insertBefore(elem, scpt); })(); window._qevents.push({ qacct: 'p-48Rosdvs3EiOc', uid: '__INSERT_EMAIL_HERE__' }); </script> <noscript> <div style="display:none;"> <img src="https//pixel.quantserve.com/pixel/p-48Rosdvs3EiOc.gif" border="0" height="1" width="1" alt="Quantcast"/> </div> </noscript> <!-- End Quantcast --> </body> </html>