You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
71 lines
3.4 KiB
HTML
71 lines
3.4 KiB
HTML
<html lang="en">
|
|
<head>
|
|
<title>PDP-11-Syntax - Using as</title>
|
|
<meta http-equiv="Content-Type" content="text/html">
|
|
<meta name="description" content="Using as">
|
|
<meta name="generator" content="makeinfo 4.13">
|
|
<link title="Top" rel="start" href="index.html#Top">
|
|
<link rel="up" href="PDP_002d11_002dDependent.html#PDP_002d11_002dDependent" title="PDP-11-Dependent">
|
|
<link rel="prev" href="PDP_002d11_002dPseudos.html#PDP_002d11_002dPseudos" title="PDP-11-Pseudos">
|
|
<link rel="next" href="PDP_002d11_002dMnemonics.html#PDP_002d11_002dMnemonics" title="PDP-11-Mnemonics">
|
|
<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage">
|
|
<!--
|
|
This file documents the GNU Assembler "as".
|
|
|
|
Copyright (C) 1991-2015 Free Software Foundation, Inc.
|
|
|
|
Permission is granted to copy, distribute and/or modify this document
|
|
under the terms of the GNU Free Documentation License, Version 1.3
|
|
or any later version published by the Free Software Foundation;
|
|
with no Invariant Sections, with no Front-Cover Texts, and with no
|
|
Back-Cover Texts. A copy of the license is included in the
|
|
section entitled ``GNU Free Documentation License''.
|
|
|
|
-->
|
|
<meta http-equiv="Content-Style-Type" content="text/css">
|
|
<style type="text/css"><!--
|
|
pre.display { font-family:inherit }
|
|
pre.format { font-family:inherit }
|
|
pre.smalldisplay { font-family:inherit; font-size:smaller }
|
|
pre.smallformat { font-family:inherit; font-size:smaller }
|
|
pre.smallexample { font-size:smaller }
|
|
pre.smalllisp { font-size:smaller }
|
|
span.sc { font-variant:small-caps }
|
|
span.roman { font-family:serif; font-weight:normal; }
|
|
span.sansserif { font-family:sans-serif; font-weight:normal; }
|
|
--></style>
|
|
</head>
|
|
<body>
|
|
<div class="node">
|
|
<a name="PDP-11-Syntax"></a>
|
|
<a name="PDP_002d11_002dSyntax"></a>
|
|
<p>
|
|
Next: <a rel="next" accesskey="n" href="PDP_002d11_002dMnemonics.html#PDP_002d11_002dMnemonics">PDP-11-Mnemonics</a>,
|
|
Previous: <a rel="previous" accesskey="p" href="PDP_002d11_002dPseudos.html#PDP_002d11_002dPseudos">PDP-11-Pseudos</a>,
|
|
Up: <a rel="up" accesskey="u" href="PDP_002d11_002dDependent.html#PDP_002d11_002dDependent">PDP-11-Dependent</a>
|
|
<hr>
|
|
</div>
|
|
|
|
<h4 class="subsection">9.33.3 PDP-11 Assembly Language Syntax</h4>
|
|
|
|
<p><a name="index-PDP_002d11-syntax-1797"></a>
|
|
<a name="index-DEC-syntax-1798"></a><a name="index-BSD-syntax-1799"></a><code>as</code> supports both DEC syntax and BSD syntax. The only
|
|
difference is that in DEC syntax, a <code>#</code> character is used to denote
|
|
an immediate constants, while in BSD syntax the character for this
|
|
purpose is <code>$</code>.
|
|
|
|
<p><a name="index-PDP_002d11-general_002dpurpose-register-syntax-1800"></a>general-purpose registers are named <code>r0</code> through <code>r7</code>.
|
|
Mnemonic alternatives for <code>r6</code> and <code>r7</code> are <code>sp</code> and
|
|
<code>pc</code>, respectively.
|
|
|
|
<p><a name="index-PDP_002d11-floating_002dpoint-register-syntax-1801"></a>Floating-point registers are named <code>ac0</code> through <code>ac3</code>, or
|
|
alternatively <code>fr0</code> through <code>fr3</code>.
|
|
|
|
<p><a name="index-PDP_002d11-comments-1802"></a>Comments are started with a <code>#</code> or a <code>/</code> character, and extend
|
|
to the end of the line. (FIXME: clash with immediates?)
|
|
|
|
<p><a name="index-PDP_002d11-line-separator-1803"></a>Multiple statements on the same line can be separated by the ‘<samp><span class="samp">;</span></samp>’ character.
|
|
|
|
</body></html>
|
|
|