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<h4 class="subsection">9.48.6 VAX Operands</h4>
<p><a name="index-VAX-operand-notation-2361"></a><a name="index-operand-notation_002c-VAX-2362"></a><a name="index-immediate-character_002c-VAX-2363"></a><a name="index-VAX-immediate-character-2364"></a>The immediate character is ‘<samp><span class="samp">$</span></samp>’ for Unix compatibility, not
‘<samp><span class="samp">#</span></samp>’ as DEC writes it.
<p><a name="index-indirect-character_002c-VAX-2365"></a><a name="index-VAX-indirect-character-2366"></a>The indirect character is ‘<samp><span class="samp">*</span></samp>’ for Unix compatibility, not
‘<samp><span class="samp">@</span></samp>’ as DEC writes it.
<p><a name="index-displacement-sizing-character_002c-VAX-2367"></a><a name="index-VAX-displacement-sizing-character-2368"></a>The displacement sizing character is ‘<samp><span class="samp">`</span></samp>’ (an accent grave) for
Unix compatibility, not ‘<samp><span class="samp">^</span></samp>’ as DEC writes it. The letter
preceding ‘<samp><span class="samp">`</span></samp>’ may have either case. ‘<samp><span class="samp">G</span></samp>’ is not
understood, but all other letters (<code>b i l s w</code>) are understood.
<p><a name="index-register-names_002c-VAX-2369"></a><a name="index-VAX-register-names-2370"></a>Register names understood are <code>r0 r1 r2 ... r15 ap fp sp
pc</code>. Upper and lower case letters are equivalent.
<p>For instance
<pre class="smallexample"> tstb *w`$4(r5)
</pre>
<p>Any expression is permitted in an operand. Operands are comma
separated.
<!-- There is some bug to do with recognizing expressions -->
<!-- in operands, but I forget what it is. It is -->
<!-- a syntax clash because () is used as an address mode -->
<!-- and to encapsulate sub-expressions. -->
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