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<h4 class="subsection">9.24.3 Symbolic Operand Modifiers</h4>
<p><a name="index-M68HC11-modifiers-1418"></a><a name="index-syntax_002c-M68HC11-1419"></a>
The assembler supports several modifiers when using symbol addresses
in 68HC11 and 68HC12 instruction operands. The general syntax is
the following:
<pre class="smallexample"> %modifier(symbol)
</pre>
<a name="index-symbol-modifiers-1420"></a>
<dl><dt><code>%addr</code><dd>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).
<br><dt><code>%page</code><dd>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.
<br><dt><code>%hi</code><dd>This modifier indicates to use the 8-bit high part of the physical
address of the symbol.
<br><dt><code>%lo</code><dd>This modifier indicates to use the 8-bit low part of the physical
address of the symbol.
</dl>
<p>For example a 68HC12 call to a function ‘<samp><span class="samp">foo_example</span></samp>’ stored in memory
expansion part could be written as follows:
<pre class="smallexample"> call %addr(foo_example),%page(foo_example)
</pre>
<p>and this is equivalent to
<pre class="smallexample"> call foo_example
</pre>
<p>And for 68HC11 it could be written as follows:
<pre class="smallexample"> ldab #%page(foo_example)
stab _page_switch
jsr %addr(foo_example)
</pre>
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