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Previous: <a rel="previous" accesskey="p" href="H8_002f300_002dRegs.html#H8_002f300_002dRegs">H8/300-Regs</a>,
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<h5 class="subsubsection">9.12.2.3 Addressing Modes</h5>
<p><a name="index-addressing-modes_002c-H8_002f300-951"></a><a name="index-H8_002f300-addressing-modes-952"></a>as understands the following addressing modes for the H8/300:
<dl>
<dt><code>r</code><var>n</var><dd>Register direct
<br><dt><code>@r</code><var>n</var><dd>Register indirect
<br><dt><code>@(</code><var>d</var><code>, r</code><var>n</var><code>)</code><dt><code>@(</code><var>d</var><code>:16, r</code><var>n</var><code>)</code><dt><code>@(</code><var>d</var><code>:24, r</code><var>n</var><code>)</code><dd>Register indirect: 16-bit or 24-bit displacement <var>d</var> from register
<var>n</var>. (24-bit displacements are only meaningful on the H8/300H.)
<br><dt><code>@r</code><var>n</var><code>+</code><dd>Register indirect with post-increment
<br><dt><code>@-r</code><var>n</var><dd>Register indirect with pre-decrement
<br><dt><code>@</code><var>aa</var><dt><code>@</code><var>aa</var><code>:8</code><dt><code>@</code><var>aa</var><code>:16</code><dt><code>@</code><var>aa</var><code>:24</code><dd>Absolute address <code>aa</code>. (The address size ‘<samp><span class="samp">:24</span></samp>’ only makes
sense on the H8/300H.)
<br><dt><code>#</code><var>xx</var><dt><code>#</code><var>xx</var><code>:8</code><dt><code>#</code><var>xx</var><code>:16</code><dt><code>#</code><var>xx</var><code>:32</code><dd>Immediate data <var>xx</var>. You may specify the ‘<samp><span class="samp">:8</span></samp>’, ‘<samp><span class="samp">:16</span></samp>’, or
‘<samp><span class="samp">:32</span></samp>’ for clarity, if you wish; but <code>as</code> neither
requires this nor uses it—the data size required is taken from
context.
<br><dt><code>@@</code><var>aa</var><dt><code>@@</code><var>aa</var><code>:8</code><dd>Memory indirect. You may specify the ‘<samp><span class="samp">:8</span></samp>’ for clarity, if you
wish; but <code>as</code> neither requires this nor uses it.
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