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17.12 多时钟的支持</div>
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多时钟序列和特性可以使用下列的语法说明。</p></div>
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<a href="00868.html" target="topic">第十七章 断言</a></p></div>
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描述 </div></td></tr><tr>
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<a href="00152.html" target="topic">17.12.1 多时钟控制序列</a> </div></td><td class="Element206" valign="top" width="50%">
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Multiply-clocked sequences are built by concatenating singly-clocked subsequences using the single-delay concatenation operator ##1. This operator is non-overlapping and synchronizes between the clocks of the two sequences. The single delay indicated by ##1 is understood to be from the endpoint of the first sequence, which occurs at a tick of the first clock, to the nearest strictly subsequent tick of the second clock, where the second sequence begins.<br><br>For example, consider </div></td></tr><tr>
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<a href="00153.html" target="topic">17.12.2 多时钟控制特性</a> </div></td><td class="Element206" valign="top" width="50%">
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As in the case of singly-clocked properties, the result of evaluating a multiply-clocked property is either true or false. Multiply-clocked properties can be formed in a number of ways.<br><br>Multiply-clocked sequences are themselves multiply-clocked properties. For example, </div></td></tr><tr>
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<a href="00154.html" target="topic">17.12.3 时钟流</a> </div></td><td class="Element206" valign="top" width="50%">
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Throughout this subsection, c, d denote clocking event expressions and v, w, x, y, z denote sequences with no clocking events.<br><br>Clock flow allows the scope of a clocking event to extend in a natural way through various parts of multiplyclocked sequences and properties and reduces the number of places at which the same clocking event must be specified.<br><br>Intuitively, clock flow provides that in a multiply-clocked sequence or property the scope of a clocking event flows left-to-right across linear operators (e.g., repetition, concatenation, negation, implication) and distributes to the operands of branching operators (e.g., conjunction, disjunction, intersection, if...else) until... <a href="00154.html" target="topic">more</a> </div></td></tr><tr>
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<a href="00155.html" target="topic">17.12.4 例子</a> </div></td><td class="Element206" valign="top" width="50%">
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The following are examples of multiple-clock specifications: </div></td></tr><tr>
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<a href="00156.html" target="topic">17.12.5 在多时钟语境中检测和使用一个序列的结束点</a> </div></td><td class="Element206" valign="top" width="50%">
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To detect the end point of a sequence when the clock of the source sequence is different than the destination sequence, method matched on the source sequence is used. The end point of a sequence is reached whenever there is a match on its expression. The occurrence of the end point can be tested in any sequence expression by using the method ended when the clocks of the source and destination sequences are the same, while method matched is used when the clocks are different.<br><br>The syntax of the matched method is: </div></td></tr></table></div></div>
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