一、题目

Make a decade counter that counts 1 through 10, inclusive. The reset input is synchronous, and should reset the counter to 1.

Module Declaration

module top_module ( input clk, input reset, output [3:0] q);

二、分析

同步高有效复位，计数器变为1；否则，计数器从1加到10，然后恢复为1，再加到10

三、代码实现

module top_module ( input clk, input reset, output reg[3:0] q); always@(posedge clk) if(reset) q<=4'd1; else if(q==4'd10) q<=4'd1; else q<=q+4'd1; endmodule 或者 module top_module ( input clk, input reset, output [3:0] q); reg [3:0]cnt; always @(posedge clk)begin if(reset|cnt==4'd10) cnt<=4'd1; else cnt<=cnt+4'd1; end assign q=cnt; endmodule

四、时序