题解 | #游戏机计费程序#（简单版本）

`timescale 1ns/1ns

module game_count
    (
		input rst_n, //异位复位信号，低电平有效
        input clk, 	//时钟信号
        input [9:0]money,
        input set,
		input boost,
		output reg[9:0]remain,
		output reg yellow,
		output reg red
    );
//=========================================================================\\
//*****************************define sinals*******************************\\
//=========================================================================\\



//=========================================================================\\
//*****************************main code***********************************\\
//=========================================================================\\


always@(posedge clk or negedge rst_n)begin
    if(!rst_n)
        remain <= 'd0             ;
    else if(set)
        remain <= remain + money  ;
    else if(remain == 'd0)
        remain <= 'd0             ;
    else if(boost == 1'b1)
        remain <= remain - 'd2    ;
    else if(boost == 1'b0)
        remain <= remain - 'd1    ;  
    else
        remain <= remain          ; 
end

always@(posedge clk or negedge rst_n)begin
    if(!rst_n)begin
          yellow <= 1'b0   ;
          red    <= 1'b0   ;
    end
    else if(remain > 'd0 && remain < 'd10)begin
          yellow <= 1'b1   ;
          red    <= 1'b0   ;
    end
    else if(remain == 'd0)begin
          yellow <= 1'b0   ;
          red    <= 1'b1   ;
    end
    else begin
          yellow <= 1'b0   ;
          red    <= 1'b0   ;
    end
end


    
endmodule