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<a name="M68HC11_002dModifiers"></a>
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<hr>
<a name="Symbolic-Operand-Modifiers-1"></a>
<h4 class="subsection">9.23.3 Symbolic Operand Modifiers</h4>

<a name="index-M68HC11-modifiers"></a>
<a name="index-syntax_002c-M68HC11-1"></a>

<p>The assembler supports several modifiers when using symbol addresses
in 68HC11 and 68HC12 instruction operands.  The general syntax is
the following:
</p>
<div class="smallexample">
<pre class="smallexample">%modifier(symbol)
</pre></div>

<dl compact="compact">
<dd><a name="index-symbol-modifiers-3"></a>
</dd>
<dt><code>%addr</code></dt>
<dd><p>This modifier indicates to the assembler and linker to use
the 16-bit physical address corresponding to the symbol.  This is intended
to be used on memory window systems to map a symbol in the memory bank window.
If the symbol is in a memory expansion part, the physical address
corresponds to the symbol address within the memory bank window.
If the symbol is not in a memory expansion part, this is the symbol address
(using or not using the %addr modifier has no effect in that case).
</p>
</dd>
<dt><code>%page</code></dt>
<dd><p>This modifier indicates to use the memory page number corresponding
to the symbol.  If the symbol is in a memory expansion part, its page
number is computed by the linker as a number used to map the page containing
the symbol in the memory bank window.  If the symbol is not in a memory
expansion part, the page number is 0.
</p>
</dd>
<dt><code>%hi</code></dt>
<dd><p>This modifier indicates to use the 8-bit high part of the physical
address of the symbol.
</p>
</dd>
<dt><code>%lo</code></dt>
<dd><p>This modifier indicates to use the 8-bit low part of the physical
address of the symbol.
</p>
</dd>
</dl>

<p>For example a 68HC12 call to a function &lsquo;<samp>foo_example</samp>&rsquo; stored in memory
expansion part could be written as follows:
</p>
<div class="smallexample">
<pre class="smallexample">call %addr(foo_example),%page(foo_example)
</pre></div>

<p>and this is equivalent to
</p>
<div class="smallexample">
<pre class="smallexample">call foo_example
</pre></div>

<p>And for 68HC11 it could be written as follows:
</p>
<div class="smallexample">
<pre class="smallexample">ldab #%page(foo_example)
stab _page_switch
jsr  %addr(foo_example)
</pre></div>

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