一、题目Design a 1-12 counter with the following inputs and outputs:ResetSynchronous active-high reset that forces the counter to 1EnableSet high for the counter to runClkPositive edge-triggered clock inputQ[3:0]The output of the counterc_enable, c_load, c_d[3:0]Control signals going to the provided 4-bit counter, so correct operation can be verified.You have the following components available:the 4-bit binary counter (count4) below, which has Enable and synchronous parallel-load inputs (load has higher priority than enable). Thecount4module is provided to you. Instantiate it in your circuit.logic gatesmodule count4( input clk, input enable, input load, input [3:0] d, output reg [3:0] Q );Thec_enable,c_load, andc_doutputs are the signals that go to the internal countersenable,load, anddinputs, respectively. Their purpose is to allow these signals to be checked for correctness.Module Declarationmodule top_module ( input clk, input reset, input enable, output [3:0] Q, output c_enable, output c_load, output [3:0] c_d );二、分析不是很理解其实子模块的例化可以根据子模块的端口命名确定。Q[3:0]The output of the counter。即在子模块作为计数器输出。c_enable作为内部寄存器的使能直接与顶层模块的使能相连。要处理的只有三个信号c_enable, c_load, c_d[3:0]。三、 代码实现module top_module ( input clk, input reset, input enable, output reg[3:0] Q, output c_enable, output c_load, output [3:0] c_d ); // assign c_enableenable; always(*) if(reset)begin c_load1b1; c_d4d1; end else if(enable 1b1 Q 4d12)begin c_load1b1; c_d4d1; end else begin c_load1b0; c_d4d0; end count4 the_counter (.clk(clk), .enable(enable), .load(c_load), .d(c_d) ,.Q(Q) ); endmodule 或者 module top_module ( input clk, input reset, input enable, output [3:0] Q, output c_enable, output c_load, output [3:0] c_d ); // count4 the_counter (clk, c_enable, c_load, c_d,Q ); assign c_enableenable; assign c_loadreset|(enable Q4d12); assign c_d1; endmodule四、时序