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.
126 lines
6.8 KiB
HTML
126 lines
6.8 KiB
HTML
<html lang="en">
|
|
<head>
|
|
<title>XGATE-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="XGATE_002dDependent.html#XGATE_002dDependent" title="XGATE-Dependent">
|
|
<link rel="prev" href="XGATE_002dOpts.html#XGATE_002dOpts" title="XGATE-Opts">
|
|
<link rel="next" href="XGATE_002dDirectives.html#XGATE_002dDirectives" title="XGATE-Directives">
|
|
<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="XGATE-Syntax"></a>
|
|
<a name="XGATE_002dSyntax"></a>
|
|
<p>
|
|
Next: <a rel="next" accesskey="n" href="XGATE_002dDirectives.html#XGATE_002dDirectives">XGATE-Directives</a>,
|
|
Previous: <a rel="previous" accesskey="p" href="XGATE_002dOpts.html#XGATE_002dOpts">XGATE-Opts</a>,
|
|
Up: <a rel="up" accesskey="u" href="XGATE_002dDependent.html#XGATE_002dDependent">XGATE-Dependent</a>
|
|
<hr>
|
|
</div>
|
|
|
|
<h4 class="subsection">9.50.2 Syntax</h4>
|
|
|
|
<p><a name="index-XGATE-syntax-2398"></a><a name="index-syntax_002c-XGATE-2399"></a>
|
|
In XGATE RISC syntax, the instruction name comes first and it may
|
|
be followed by up to three operands. Operands are separated by commas
|
|
(‘<samp><span class="samp">,</span></samp>’). <code>as</code> will complain if too many operands are specified
|
|
for a given instruction. The same will happen if you specified too few
|
|
operands.
|
|
|
|
<pre class="smallexample"> nop
|
|
ldl #23
|
|
CMP R1, R2
|
|
</pre>
|
|
<p><a name="index-line-comment-character_002c-XGATE-2400"></a><a name="index-XGATE-line-comment-character-2401"></a>The presence of a ‘<samp><span class="samp">;</span></samp>’ character or a ‘<samp><span class="samp">!</span></samp>’ character anywhere
|
|
on a line indicates the start of a comment that extends to the end of
|
|
that line.
|
|
|
|
<p>A ‘<samp><span class="samp">*</span></samp>’ or a ‘<samp><span class="samp">#</span></samp>’ character at the start of a line also
|
|
introduces a line comment, but these characters do not work elsewhere
|
|
on the line. If the first character of the line is a ‘<samp><span class="samp">#</span></samp>’ then as
|
|
well as starting a comment, the line could also be logical line number
|
|
directive (see <a href="Comments.html#Comments">Comments</a>) or a preprocessor control command
|
|
(see <a href="Preprocessing.html#Preprocessing">Preprocessing</a>).
|
|
|
|
<p><a name="index-line-separator_002c-XGATE-2402"></a><a name="index-statement-separator_002c-XGATE-2403"></a><a name="index-XGATE-line-separator-2404"></a>The XGATE assembler does not currently support a line separator
|
|
character.
|
|
|
|
<p><a name="index-XGATE-addressing-modes-2405"></a><a name="index-addressing-modes_002c-XGATE-2406"></a>The following addressing modes are understood for XGATE:
|
|
<dl>
|
|
<dt><dfn>Inherent</dfn><dd>‘<samp></samp>’
|
|
|
|
<br><dt><dfn>Immediate 3 Bit Wide</dfn><dd>‘<samp><span class="samp">#</span><var>number</var></samp>’
|
|
|
|
<br><dt><dfn>Immediate 4 Bit Wide</dfn><dd>‘<samp><span class="samp">#</span><var>number</var></samp>’
|
|
|
|
<br><dt><dfn>Immediate 8 Bit Wide</dfn><dd>‘<samp><span class="samp">#</span><var>number</var></samp>’
|
|
|
|
<br><dt><dfn>Monadic Addressing</dfn><dd>‘<samp><var>reg</var></samp>’
|
|
|
|
<br><dt><dfn>Dyadic Addressing</dfn><dd>‘<samp><var>reg</var><span class="samp">, </span><var>reg</var></samp>’
|
|
|
|
<br><dt><dfn>Triadic Addressing</dfn><dd>‘<samp><var>reg</var><span class="samp">, </span><var>reg</var><span class="samp">, </span><var>reg</var></samp>’
|
|
|
|
<br><dt><dfn>Relative Addressing 9 Bit Wide</dfn><dd>‘<samp><span class="samp">*</span><var>symbol</var></samp>’
|
|
|
|
<br><dt><dfn>Relative Addressing 10 Bit Wide</dfn><dd>‘<samp><span class="samp">*</span><var>symbol</var></samp>’
|
|
|
|
<br><dt><dfn>Index Register plus Immediate Offset</dfn><dd>‘<samp><var>reg</var><span class="samp">, (</span><var>reg</var><span class="samp">, #</span><var>number</var><span class="samp">)</span></samp>’
|
|
|
|
<br><dt><dfn>Index Register plus Register Offset</dfn><dd>‘<samp><var>reg</var><span class="samp">, </span><var>reg</var><span class="samp">, </span><var>reg</var></samp>’
|
|
|
|
<br><dt><dfn>Index Register plus Register Offset with Post-increment</dfn><dd>‘<samp><var>reg</var><span class="samp">, </span><var>reg</var><span class="samp">, </span><var>reg</var><span class="samp">+</span></samp>’
|
|
|
|
<br><dt><dfn>Index Register plus Register Offset with Pre-decrement</dfn><dd>‘<samp><var>reg</var><span class="samp">, </span><var>reg</var><span class="samp">, -</span><var>reg</var></samp>’
|
|
|
|
<p>The register can be either ‘<samp><span class="samp">R0</span></samp>’, ‘<samp><span class="samp">R1</span></samp>’, ‘<samp><span class="samp">R2</span></samp>’, ‘<samp><span class="samp">R3</span></samp>’,
|
|
‘<samp><span class="samp">R4</span></samp>’, ‘<samp><span class="samp">R5</span></samp>’, ‘<samp><span class="samp">R6</span></samp>’ or ‘<samp><span class="samp">R7</span></samp>’.
|
|
|
|
</dl>
|
|
|
|
<p>Convience macro opcodes to deal with 16-bit values have been added.
|
|
|
|
<dl>
|
|
<dt><dfn>Immediate 16 Bit Wide</dfn><dd>‘<samp><span class="samp">#</span><var>number</var></samp>’, or ‘<samp><span class="samp">*</span><var>symbol</var></samp>’
|
|
|
|
<p>For example:
|
|
|
|
<pre class="smallexample"> ldw R1, #1024
|
|
ldw R3, timer
|
|
ldw R1, (R1, #0)
|
|
COM R1
|
|
stw R2, (R1, #0)
|
|
</pre>
|
|
</dl>
|
|
|
|
</body></html>
|
|
|