mirror of
https://github.com/steveicarus/iverilog.git
synced 2026-09-05 08:52:33 +02:00
Stephen Williams
cea237b407
By adding ivtest to the iverilog source tree, it is easier to keep the regression test synchronized with the source that is being tested. This should be especially helpful for PRs that add a new feature, and have a matching ivtest PR with the regression test for that feature.
73 lines
884 B
Verilog
73 lines
884 B
Verilog
module dff (clk, d, q) ;
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input d,clk;
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output q;
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reg q_out;
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wire q;
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specify
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specparam tR_clk_q = 100,
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tF_clk_q = 150;
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(clk,d => q) = (tR_clk_q,tF_clk_q);
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endspecify
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always @(posedge clk)
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q_out <= d;
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buf u_buf (q,q_out);
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endmodule
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module test;
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reg clk, d;
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reg err;
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time pos_lvl,neg_lvl;
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dff u_dff (clk,d,q);
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initial
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begin
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// $dumpfile("test.vcd");
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// $dumpvars(0,test);
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err = 0;
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d = 0;
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clk = 0;
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#200;
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clk = 1;
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#200;
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clk = 0;
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#200;
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clk = 1;
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#200;
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clk = 0;
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#200;
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clk = 1;
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$display("pos_lvl=%t neg_lvl=%t",pos_lvl,neg_lvl);
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if((pos_lvl != 700) && (neg_lvl != 350))
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$display("FAILED");
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else
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$display("PASSED");
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end
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always @(posedge q)
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pos_lvl = $time;
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always @(negedge q)
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neg_lvl = $time;
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initial
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begin
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#250;
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d = 1;
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#450;
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d = 0;
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end
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endmodule
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