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<a name="M68HC11-Modifiers"></a>
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Next: <a rel="next" accesskey="n" href="M68HC11_002dDirectives.html#M68HC11_002dDirectives">M68HC11-Directives</a>,
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<h4 class="subsection">9.24.3 Symbolic Operand Modifiers</h4>
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<p><a name="index-M68HC11-modifiers-1418"></a><a name="index-syntax_002c-M68HC11-1419"></a>
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The assembler supports several modifiers when using symbol addresses
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in 68HC11 and 68HC12 instruction operands. The general syntax is
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the following:
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<pre class="smallexample"> %modifier(symbol)
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</pre>
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<a name="index-symbol-modifiers-1420"></a>
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<dl><dt><code>%addr</code><dd>This modifier indicates to the assembler and linker to use
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the 16-bit physical address corresponding to the symbol. This is intended
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to be used on memory window systems to map a symbol in the memory bank window.
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If the symbol is in a memory expansion part, the physical address
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corresponds to the symbol address within the memory bank window.
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If the symbol is not in a memory expansion part, this is the symbol address
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(using or not using the %addr modifier has no effect in that case).
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<br><dt><code>%page</code><dd>This modifier indicates to use the memory page number corresponding
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to the symbol. If the symbol is in a memory expansion part, its page
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number is computed by the linker as a number used to map the page containing
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the symbol in the memory bank window. If the symbol is not in a memory
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expansion part, the page number is 0.
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<br><dt><code>%hi</code><dd>This modifier indicates to use the 8-bit high part of the physical
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address of the symbol.
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<br><dt><code>%lo</code><dd>This modifier indicates to use the 8-bit low part of the physical
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address of the symbol.
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</dl>
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<p>For example a 68HC12 call to a function ‘<samp><span class="samp">foo_example</span></samp>’ stored in memory
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expansion part could be written as follows:
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<pre class="smallexample"> call %addr(foo_example),%page(foo_example)
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</pre>
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<p>and this is equivalent to
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<pre class="smallexample"> call foo_example
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</pre>
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<p>And for 68HC11 it could be written as follows:
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<pre class="smallexample"> ldab #%page(foo_example)
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stab _page_switch
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jsr %addr(foo_example)
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</pre>
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