122 lines
5.9 KiB
HTML
122 lines
5.9 KiB
HTML
<html lang="en">
|
|
<head>
|
|
<title>M68HC11-Syntax - Using as</title>
|
|
<meta http-equiv="Content-Type" content="text/html">
|
|
<meta name="description" content="Using as">
|
|
<meta name="generator" content="makeinfo 4.7">
|
|
<link title="Top" rel="start" href="index.html#Top">
|
|
<link rel="up" href="M68HC11_002dDependent.html#M68HC11_002dDependent" title="M68HC11-Dependent">
|
|
<link rel="prev" href="M68HC11_002dOpts.html#M68HC11_002dOpts" title="M68HC11-Opts">
|
|
<link rel="next" href="M68HC11_002dModifiers.html#M68HC11_002dModifiers" title="M68HC11-Modifiers">
|
|
<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage">
|
|
<!--
|
|
This file documents the GNU Assembler "as".
|
|
|
|
Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001, 2002,
|
|
2006, 2007 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 1.1
|
|
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''.
|
|
|
|
man end-->
|
|
<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; }
|
|
--></style>
|
|
</head>
|
|
<body>
|
|
<div class="node">
|
|
<p>
|
|
<a name="M68HC11_002dSyntax"></a>Next: <a rel="next" accesskey="n" href="M68HC11_002dModifiers.html#M68HC11_002dModifiers">M68HC11-Modifiers</a>,
|
|
Previous: <a rel="previous" accesskey="p" href="M68HC11_002dOpts.html#M68HC11_002dOpts">M68HC11-Opts</a>,
|
|
Up: <a rel="up" accesskey="u" href="M68HC11_002dDependent.html#M68HC11_002dDependent">M68HC11-Dependent</a>
|
|
<hr><br>
|
|
</div>
|
|
|
|
<h4 class="subsection">9.21.2 Syntax</h4>
|
|
|
|
<p><a name="index-M68HC11-syntax-1159"></a><a name="index-syntax_002c-M68HC11-1160"></a>
|
|
In the M68HC11 syntax, the instruction name comes first and it may
|
|
be followed by one or several operands (up to three). Operands are
|
|
separated by comma (<span class="samp">,</span>). In the normal mode,
|
|
<code>as</code> will complain if too many operands are specified for
|
|
a given instruction. In the MRI mode (turned on with <span class="samp">-M</span> option),
|
|
it will treat them as comments. Example:
|
|
|
|
<pre class="smallexample"> inx
|
|
lda #23
|
|
bset 2,x #4
|
|
brclr *bot #8 foo
|
|
</pre>
|
|
<p><a name="index-M68HC11-addressing-modes-1161"></a><a name="index-addressing-modes_002c-M68HC11-1162"></a>The following addressing modes are understood for 68HC11 and 68HC12:
|
|
<dl>
|
|
<dt><dfn>Immediate</dfn><dd><span class="samp">#</span><var>number</var>
|
|
|
|
<br><dt><dfn>Address Register</dfn><dd><var>number</var><span class="samp">,X</span>, <var>number</var><span class="samp">,Y</span>
|
|
|
|
<p>The <var>number</var> may be omitted in which case 0 is assumed.
|
|
|
|
<br><dt><dfn>Direct Addressing mode</dfn><dd><span class="samp">*</span><var>symbol</var>, or <span class="samp">*</span><var>digits</var>
|
|
|
|
<br><dt><dfn>Absolute</dfn><dd><var>symbol</var>, or <var>digits</var>
|
|
</dl>
|
|
|
|
<p>The M68HC12 has other more complex addressing modes. All of them
|
|
are supported and they are represented below:
|
|
|
|
<dl>
|
|
<dt><dfn>Constant Offset Indexed Addressing Mode</dfn><dd><var>number</var><span class="samp">,</span><var>reg</var>
|
|
|
|
<p>The <var>number</var> may be omitted in which case 0 is assumed.
|
|
The register can be either <span class="samp">X</span>, <span class="samp">Y</span>, <span class="samp">SP</span> or
|
|
<span class="samp">PC</span>. The assembler will use the smaller post-byte definition
|
|
according to the constant value (5-bit constant offset, 9-bit constant
|
|
offset or 16-bit constant offset). If the constant is not known by
|
|
the assembler it will use the 16-bit constant offset post-byte and the value
|
|
will be resolved at link time.
|
|
|
|
<br><dt><dfn>Offset Indexed Indirect</dfn><dd><span class="samp">[</span><var>number</var><span class="samp">,</span><var>reg</var><span class="samp">]</span>
|
|
|
|
<p>The register can be either <span class="samp">X</span>, <span class="samp">Y</span>, <span class="samp">SP</span> or <span class="samp">PC</span>.
|
|
|
|
<br><dt><dfn>Auto Pre-Increment/Pre-Decrement/Post-Increment/Post-Decrement</dfn><dd><var>number</var><span class="samp">,-</span><var>reg</var>
|
|
<var>number</var><span class="samp">,+</span><var>reg</var>
|
|
<var>number</var><span class="samp">,</span><var>reg</var><span class="samp">-</span>
|
|
<var>number</var><span class="samp">,</span><var>reg</var><span class="samp">+</span>
|
|
|
|
<p>The number must be in the range <span class="samp">-8</span>..<span class="samp">+8</span> and must not be 0.
|
|
The register can be either <span class="samp">X</span>, <span class="samp">Y</span>, <span class="samp">SP</span> or <span class="samp">PC</span>.
|
|
|
|
<br><dt><dfn>Accumulator Offset</dfn><dd><var>acc</var><span class="samp">,</span><var>reg</var>
|
|
|
|
<p>The accumulator register can be either <span class="samp">A</span>, <span class="samp">B</span> or <span class="samp">D</span>.
|
|
The register can be either <span class="samp">X</span>, <span class="samp">Y</span>, <span class="samp">SP</span> or <span class="samp">PC</span>.
|
|
|
|
<br><dt><dfn>Accumulator D offset indexed-indirect</dfn><dd><span class="samp">[D,</span><var>reg</var><span class="samp">]</span>
|
|
|
|
<p>The register can be either <span class="samp">X</span>, <span class="samp">Y</span>, <span class="samp">SP</span> or <span class="samp">PC</span>.
|
|
|
|
</dl>
|
|
|
|
<p>For example:
|
|
|
|
<pre class="smallexample"> ldab 1024,sp
|
|
ldd [10,x]
|
|
orab 3,+x
|
|
stab -2,y-
|
|
ldx a,pc
|
|
sty [d,sp]
|
|
</pre>
|
|
</body></html>
|
|
|