https://www.ndwiki.org/index.php?action=history&feed=atom&title=Source_register Source register - Revision history 2026-06-28T02:03:39Z Revision history for this page on the wiki MediaWiki 1.43.8 https://www.ndwiki.org/index.php?title=Source_register&diff=1468&oldid=prev TArntsen: Source Register description (for ROP instructions) 2010-07-26T15:54:58Z <p>Source Register description (for ROP instructions)</p> <p><b>New page</b></p><div>&#039;&#039;&#039;Source register&#039;&#039;&#039; (&#039;&#039;abbr. &#039;&#039;&#039;&lt;sr&gt;&#039;&#039;&#039;&#039;&#039;) is encoded in bits 5..3 of Register Operation (ROP) instructions.<br /> <br /> The source registers are specified as follows:<br /> {| class=&quot;wikitable&quot;<br /> |-<br /> ! [[MAC]] mnemonic !! Register name !! Value !! Octal value to add to ROP instruction<br /> |-<br /> | SD || D register || 1 || 10&lt;sub&gt;&lt;small&gt;8&lt;/small&gt;&lt;/sub&gt;<br /> |-<br /> | SP || Program counter || 2 || 20&lt;sub&gt;&lt;small&gt;8&lt;/small&gt;&lt;/sub&gt;<br /> |-<br /> | SB || B register || 3 || 30&lt;sub&gt;&lt;small&gt;8&lt;/small&gt;&lt;/sub&gt;<br /> |-<br /> | SL || L register || 4 || 40&lt;sub&gt;&lt;small&gt;8&lt;/small&gt;&lt;/sub&gt;<br /> |-<br /> | SA || A register || 5 || 50&lt;sub&gt;&lt;small&gt;8&lt;/small&gt;&lt;/sub&gt;<br /> |-<br /> | ST || T register || 6 || 60&lt;sub&gt;&lt;small&gt;8&lt;/small&gt;&lt;/sub&gt;<br /> |-<br /> | SX || X register || 7 || 70&lt;sub&gt;&lt;small&gt;8&lt;/small&gt;&lt;/sub&gt;<br /> |}<br /> <br /> If no source register is specified (value: 0), zero will be taken as the source register (i.e. the value 0 as input to operations).<br /> <br /> == References ==<br /> *{{ND-doc|06.014.02|Page 3-37}}<br /> *{{ND-doc|06.029.01|Pages 39-40}}<br /> <br /> [[Category:ND-100 instructions]]</div> TArntsen