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 == 1'b0)
            remain <= 'd0;
        else if(set)
            remain <= remain + money;
        else if(boost)
            remain <= remain - 'd2;
        else
            remain <= remain - 'd1;
    end

    always @(posedge clk or negedge rst_n) begin
        if(rst_n == 1'b0)
            yellow <= 1'b0;
        else if(remain < 'd10 & remain >= 'd1)
            yellow <= 1'b1;
        else
            yellow <= 1'b0;
    end

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

endmodule

刚敲完代码，居然秒通过！！