题解 | #游戏机计费程序#

`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
    );
    
    always @ (posedge clk or negedge rst_n) begin
        if (!rst_n) begin
            remain<=0;
            yellow<=0;
            red<=0;
        end
        else begin
            remain<=(set)?remain+money:(boost)?remain-2:remain-1;
            yellow<=(remain<10&&remain>0);
            red<=(remain==0);
        end
    end
        
        
        
endmodule