这是一道触发器的题目，但是仿真波形和我分析出来的不太一样下面是我的代码：
- module T_ff(input T,input clk,input rst,output reg Q, output reg Qn);
- initial
- begin
- Q <= 0;
- Qn <= 1;
- end
- always @(posedge clk,negedge rst)
- begin
- if(~rst)
- begin
- Q <= 0;
- Qn <= 1;
- end
- else
- case(T)
- 1'b0: begin Q <= Q; Qn <= ~Q; end
- 1'b1: begin Q <= ~Q; Qn <= Q; end
- default: begin Q <= Q; Qn <= ~Q; end
- endcase
-
- end
- endmodule
- module D_ff(input D,input clk,output reg Q,output reg Qn);
- initial
- begin
- Q = 0;
- Qn = 1;
-
- end
- always @(negedge clk)
- begin
- Q <= D;
- Qn <= ~D;
- end
- endmodule
- module jK_ff(input J,input K,input clk,output reg Q,output reg Qn);
- initial
- begin
- Q = 0;
- Qn = 1;
- end
- always @(negedge clk)
- begin
-
- case({J,K})
- 2'b00: begin Q <= Q; Qn <= ~Q; end
- 2'b01: begin Q <= 0; Qn <= 1; end
- 2'b10: begin Q <= 1; Qn <= 0; end
- 2'b11: begin Q <= ~Q; Qn <= Q; end
- default: begin Q<=Q; Qn<= ~Q;end
- endcase
-
-
- end
- endmodule
- module FF(input clk, input t,output Q3);
-
- wire Q1,Q2,Q1n,Q2n,Q3n,rst;
- and(rst,Q2n,Q3n);
- T_ff t_ff(.T(t),.clk(clk),.rst(rst),.Q(Q1),.Qn(Q1n));
- D_ff d_ff(.D(Q1),.clk(clk),.Q(Q2),.Qn(Q2n));
- JK_ff jk_ff(.J(Q2),.K(Q1n),.clk(clk),.Q(Q3),.Qn(Q3n));
- endmodule
- `timescale 1ns/1ns
- module tb();
-
- reg CLK,t;
- wire Q3;
- initial
- begin
- CLK<=0;
- t<=1;
- repeat(100)#10 CLK <= ~CLK;
- end
- FF ff(.clk(CLK),.t(t),.Q3(Q3));
- endmodule
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