module traffic_lights;<br /> reg clock,red,amber,green;<br /> parameter on=1,off=0,red_tics=350,amber_tics=30,green_tics=200;<br /><br /> initial red=off;<br /> initial amber=off;<br /> initial green=off;<br /><br /> always <br /> begin<br /> red=on;<br /> light(red,red_tics);<br /> amber=on;<br /> light(amber,amber_tics);<br /> green=on;<br /> light(green,green_tics);<br /> end<br /><br />task light(tics,color);<br /> output color;<br /> input[31:0] tics;<br />begin<br /> repeat(tics)@(posedge clock);<br /> color=off;<br />end<br />endtask<br /><br />always<br /> begin<br /> #100 clock=0;<br /> #100 clock=1;<br /> end<br />endmodule<br /><br /><br />在编译时提示在19行有语法错误,但没发现什么问题 请高手指点! |
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