「HDLBits题解」Cellular automata

本专栏的目的是分享可以通过HDLBits仿真的Verilog代码以提供参考各位可同时参考我的代码和官方题解代码或许会有所收益

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module top_module(
    input clk,
    input load,
    input [511:0] data,
    output [511:0] q );

    always @ (posedge clk) begin 
        if (load) 
            q <= data ; 
		else
            q <= {1'b0, q[511:1]} ^ {q[510:0], 1'b0} ;
    end
endmodule

题目链接：Rule110 - HDLBits

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module top_module(
    input clk,
    input load,
    input [511:0] data,
    output [511:0] q
);
	always @(posedge clk) begin
		if (load) begin
			q <= data;
		end
		else begin
			q <= (((q[511:0] ^ {q[510:0], 1'b0}) & q[511:1]) | ((q[511:0] | {q[510:0], 1'b0}) & (~q[511:1])));
		end
	end
endmodule

题目链接：Conwaylife - HDLBits

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module top_module(
    input clk,
    input load,
    input [255:0] data,
    output [255:0] q ); 

    reg [255:0] q_next;
    reg [3:0] sum;

    always@(posedge clk) begin
        if(load)
            q <= data;
        else begin
            for(int i=0; i<256; i++) begin  //使用阻塞赋值，使sum得出后在该时钟周期内q立即变化，而不需要等到下个周期。
                if(i == 0)  //左上角
                    sum = q[1] + q[16] + q[17] + q[240] + q[241] + q[15] + q[31] + q[255];
                else if(i == 15)    //右上角
                    sum = q[14] + q[16] + q[0] + q[240] + q[254] + q[30] + q[31] + q[255];
                else if(i == 240)   //左下角
                    sum = q[0] + q[15] + q[239] + q[241] + q[1] + q[224] + q[225] + q[255];
                else if(i == 255)   //右下角
                    sum = q[0] + q[15] + q[14] + q[224] + q[238] + q[240] + q[239] + q[254];
                else if(0<i & i<15) //上边界
                    sum = q[i-1] + q[i+1] + q[i+15] + q[i+16] + q[i+17] + q[i+239] + q[i+240] + q[i+241];
                else if(i%16 == 0)  //左边界
                    sum = q[i-1] + q[i+1] + q[i+15] + q[i+16] + q[i+17] + q[i-16] + q[i-15] + q[i+31];
                else if(i%16 == 15) //右边界
                    sum = q[i-1] + q[i+1] + q[i+15] + q[i+16] + q[i-17] + q[i-16] + q[i-15] + q[i-31];
                else if(240<i & i<255)  //下边界
                    sum = q[i-1] + q[i+1] + q[i-17] + q[i-16] + q[i-15] + q[i-239] + q[i-240] + q[i-241];
                else //非边界
                    sum = q[i-1] + q[i+1] + q[i-17] + q[i-16] + q[i-15] + q[i+15] + q[i+16] + q[i+17];
          		
                case(sum) //根据邻居数量判断次态
                    2:q_next[i] = q[i];
                    3:q_next[i] = 1;
                    default:q_next[i] = 0;
                endcase
            end
            	q = q_next;
        end
    end
endmodule