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<h4 class="subsection">9.33.3 PDP-11 Assembly Language Syntax</h4>
<p><a name="index-PDP_002d11-syntax-1797"></a>
<a name="index-DEC-syntax-1798"></a><a name="index-BSD-syntax-1799"></a><code>as</code> supports both DEC syntax and BSD syntax. The only
difference is that in DEC syntax, a <code>#</code> character is used to denote
an immediate constants, while in BSD syntax the character for this
purpose is <code>$</code>.
<p><a name="index-PDP_002d11-general_002dpurpose-register-syntax-1800"></a>general-purpose registers are named <code>r0</code> through <code>r7</code>.
Mnemonic alternatives for <code>r6</code> and <code>r7</code> are <code>sp</code> and
<code>pc</code>, respectively.
<p><a name="index-PDP_002d11-floating_002dpoint-register-syntax-1801"></a>Floating-point registers are named <code>ac0</code> through <code>ac3</code>, or
alternatively <code>fr0</code> through <code>fr3</code>.
<p><a name="index-PDP_002d11-comments-1802"></a>Comments are started with a <code>#</code> or a <code>/</code> character, and extend
to the end of the line. (FIXME: clash with immediates?)
<p><a name="index-PDP_002d11-line-separator-1803"></a>Multiple statements on the same line can be separated by the ‘<samp><span class="samp">;</span></samp>’ character.
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