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这是一本关于verilog编程语言的教程,对学习verilog语言有帮助

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<a href="00664.html" target="topic">A.6.5 Timing control statements</a>&nbsp;</div></td><td class="Element206" valign="top" width="50%">
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procedural_timing_control_statement ::=<br>procedural_timing_control statement_or_null<br>delay_or_event_control ::=<br>delay_control<br>| event_control<br>| repeat ( expression ) event_control<br>delay_control ::=<br># delay_value<br>| # ( mintypmax_expression )<br>event_control ::=<br>@hierarchical_event_identifier<br>| @ ( event_expression )<br>| @*<br>| @ (*)<br>| @ sequence_instance<br>event_expression ::=<br>[ edge_identifier ] expression [ iff expression ]<br>| sequence_instance [ iff expression ]<br>| event_expression or event_expression<br>| event_expression , event_expression<br>procedural_timing_control ::=<br>delay_control<br>| event_control<br>| cycle_delay<br>jump_statement ::=<br>return [ expression ] ;<br>| break ;<br>| continue ;<br>wait_statement ::=<br>wait ( expression ) statement_or_null<br>| wait fork ;<br>| wait_order ( hierarchical_identifier [... <a href="00664.html" target="topic">more</a>&nbsp;</div></td></tr><tr>
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<a href="00665.html" target="topic">A.6.6 Conditional statements</a>&nbsp;</div></td><td class="Element206" valign="top" width="50%">
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conditional_statement ::=<br>if ( cond_predicate ) statement_or_null [ else statement_or_null ]<br>| unique_priority_if_statement<br>unique_priority_if_statement ::=<br>[ unique_priority ] if ( cond_predicate ) statement_or_null<br>{ else if ( cond_predicate ) statement_or_null }<br>[ else statement_or_null ]<br>unique_priority ::= unique | priority<br>cond_predicate ::=<br>expression_or_cond_pattern { &amp;&amp; expression_or_cond_pattern }<br>expression_or_cond_pattern ::=<br>expression | cond_pattern<br>cond_pattern ::= expression matches pattern&nbsp;</div></td></tr><tr>
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<a href="00666.html" target="topic">A.6.7 Case statements</a>&nbsp;</div></td><td class="Element206" valign="top" width="50%">
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case_statement ::=<br>[ unique_priority ] case_keyword ( expression ) case_item { case_item } endcase<br>| [ unique_priority ] case_keyword ( expression ) matches case_pattern_item { case_pattern_item }<br>endcase<br>case_keyword ::= case | casez | casex<br>case_item ::=<br>expression { , expression } : statement_or_null<br>| default [ : ] statement_or_null<br>case_pattern_item ::=<br>pattern [ &amp;&amp; expression ] : statement_or_null<br>| default [ : ] statement_or_null<br>randcase_statement ::=<br>randcase randcase_item { randcase_item } endcase<br>randcase_item ::= expression : statement_or_null&nbsp;</div></td></tr><tr>
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<a href="00668.html" target="topic">A.6.8 Looping statements</a>&nbsp;</div></td><td class="Element206" valign="top" width="50%">
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loop_statement ::=<br>forever statement_or_null<br>| repeat ( expression ) statement_or_null<br>| while ( expression ) statement_or_null<br>| for ( for_initialization ; expression ; for_step )<br>statement_or_null<br>| do statement_or_null while ( expression ) ;<br>| foreach ( array_identifier [ loop_variables ] ) statement<br>for_initialization ::=<br>list_of_variable_assignments<br>| data_type list_of_variable_assignments { , data_type list_of_variable_assignments }<br>for_step ::= for_step_assignment { , for_step_assignment }<br>for_step_assignment ::=<br>operator_assignment<br>| inc_or_dec_expression<br>loop_variables ::= [ index_variable_identifier ] { , [ index_variable_identifier ] }&nbsp;</div></td></tr><tr>
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<a href="00669.html" target="topic">A.6.9 Subroutine call statements</a>&nbsp;</div></td><td class="Element206" valign="top" width="50%">
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subroutine_call_statement :=<br>subroutine_call ;<br>| void ’ ( function_subroutine_call ) ;&nbsp;</div></td></tr><tr>
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<a href="00658.html" target="topic">A.6.10 Assertion statements</a>&nbsp;</div></td><td class="Element206" valign="top" width="50%">
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procedural_assertion_statement ::=<br>concurrent_assertion_statement<br>| immediate_assert_statement<br>immediate_assert_statement ::=<br>assert ( expression ) action_block&nbsp;</div></td></tr><tr>
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<a href="00659.html" target="topic">A.6.11 Clocking block</a>&nbsp;</div></td><td class="Element206" valign="top" width="50%">
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clocking_declaration ::= [ default ] clocking [ clocking_identifier ] clocking_event ;<br>{ clocking_item }<br>endclocking [ : clocking_identifier ]<br>clocking_event ::=<br>@identifier<br>| @ ( event_expression )<br>clocking_item :=<br>default default_skew ;<br>| clocking_direction list_of_clocking_decl_assign ;<br>| { attribute_instance } concurrent_assertion_item_declaration<br>default_skew ::=<br>input clocking_skew<br>| output clocking_skew<br>| input clocking_skew output clocking_skew<br>clocking_direction ::=<br>input [ clocking_skew ]<br>| output [ clocking_skew ]<br>| input [ clocking_skew ] output [ clocking_skew ]<br>| inout<br>list_of_clocking_decl_assign ::= clocking_decl_assign { , clocking_decl_assign }<br>clocking_decl_assign ::= signal_identifier [ = hierarchical_identifier ]<br>clocking_skew ::=<br>edge_identifier [ delay_control ]<br>| delay_control<br>clocking_drive ::=<br>clockvar_expression... <a href="00659.html" target="topic">more</a>&nbsp;</div></td></tr><tr>
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<a href="00660.html" target="topic">A.6.12 Randsequence</a>&nbsp;</div></td><td class="Element206" valign="top" width="50%">
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randsequence_statement ::= randsequence ( [ production_ identifier ] )<br>production { production }<br>endsequence<br>production ::= [ function_data_type ] production_name [ ( tf_port_list ) ] : rs_rule { | rs_rule } ;<br>rs_rule ::= rs_production_list [ := expression [ rs_code_block ] ]<br>rs_production_list ::=<br>rs_prod { rs_prod }<br>| rand join [ ( expression ) ] production_item production_item { production_item }<br>rs_code_block ::= { { data_declaration } { statement_or_null } }<br>rs_prod ::=<br>production_item<br>| rs_code_block<br>| rs_if_else<br>| rs_repeat<br>| rs_case<br>production_item ::= production_identifier [ ( list_of_arguments ) ]<br>rs_if_else ::= if ( expression ) production_item [ else production_item... <a href="00660.html" target="topic">more</a>&nbsp;</div></td></tr></table></div></div>
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<a href="00879.html" target="topic">附录A 形式语法</a>, <a href="01019.html" target="topic">主题</a></div>
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