未连接的端口-Verilog 综合错误

问题描述

我正在综合我的 RTL，但我一直收到错误“警告：在设计中‘DasisyChain3’端口‘m1_data[7]’未连接到任何网络 (LINT-28)。我不知道为什么它会告诉我这个。我在我的设计中包含了所有模块，它代表了 SPI 协议的某种简化版本。我有一个从主机和 DaisyChain 模块，它是我的顶级模块，是菊花链的实现。

module DaisyChain3(output [7:0] s1_buff,s2_buff,s3_buff,input EN,CLK,input [7:0] m1_data,s1_data,s2_data,s3_data);

    wire SCLK,CS,MOSI;
    wire s1_SOMI,s2_SOMI,s3_SOMI;

    SPIMaster m1(SCLK,MOSI,EN,s3_SOMI,m1_data);
    SPISlave s1(s1_SOMI,s1_buff,SCLK,s1_data);
    SPISlave s2(s2_SOMI,s1_SOMI,s2_data);
    SPISlave s3(s3_SOMI,s3_data);

endmodule

module SPIMaster(output reg SCLK,MISO,input [7:0] m_data);
    wire master_out;
    reg [4:0] count,count1,count2;
    wire [7:0] data_buff;
    wire SCLK1;
    reg master_in,c_sw,k,state,load;
    reg k1,load1;
    shiftReg register_out (master_out,data_buff,load,(~SCLK1),master_in,m_data);
assign SCLK1 = (~c_sw) | CLK;
    always@(posedge CLK) begin
        if(state) begin
            if (k == 1) begin
                state <= 0;
                c_sw <= 0;
                CS <= 1;
                count <= 0;
                k <= 0;
                load <= 0;
            end
            else begin
                state <= 1;
                c_sw <= 1;
                CS <= 0;
            end
        end
        else begin
            if (EN) begin
                state <= 1;
                c_sw <= 1;
                CS <= 0;
                count <= 0;
                k <= 0;
                load <= 1;
            end
        end
            count <= count1;
            load <= load1;
            k <= k1;
    end
    always@(posedge SCLK1) begin
        load1 <= count;
        count1 <= count;
        if (CS == 0) master_in <= MISO;
        if (count1 == 7) begin
            load1 <= 0;
        end
        else if (count1 == 15)begin
            load1 <= 0;
        end
        else begin
            load1 <= 1;
        end
        count1 <= count2;
    end
    always@(negedge SCLK1) begin
        count2 <= count1;
        k1 <= k;
        if (count2 == 23) k1 <= 1;
        else k1 <= 0;
        if (CS == 0) begin
            MOSI <= master_out;
            count2 <= count2 + 1;
        end
    end
endmodule
module SPISlave(output reg SOMI,output [7:0] data_buff,input SIMO,input [7:0] s_data);
    wire clk;
    reg slave_in;
    wire slave_out;
    shiftReg register_out (slave_out,(~CS),clk,slave_in,s_data);
    assign clk = SCLK | CS;
    always@(posedge clk) begin
        slave_in <= SIMO;
    end
    always@(negedge clk) begin
        SOMI <= slave_out;
    end
endmodule

module shiftReg(output shift_out,output reg [7:0] data_buff,input shift_write,shift_in,input [7:0] data);

    reg [7:0] buffer;
    assign shift_out = buffer[7];
    assign buffer[0] = shift_in;
    always@(posedge clk) begin
        if(shift_write == 1) begin
            buffer <= {buffer[6:0],shift_in};
        end
    end
    always@(shift_write) begin
        if(shift_write == 0) begin
            data_buff <= buffer;
            buffer <= data;
        end
    end

endmodule

解决方法

在您之前的消息中，您忘记发布 shiftReg 的代码。它就在这里，它有一个错误，这可能是造成上一个问题的原因，也可能是这个问题的原因。

您的问题是您有多个 (3) 个用于 buffer 的驱动程序：

    assign buffer[0] = shift_in; <<< driver 1
    always@(posedge clk) begin
        if(shift_write == 1) begin
            buffer <= {buffer[6:0],shift_in}; <<< driver 2
        end
    end
    always@(shift_write) begin
        if(shift_write == 0) begin
            data_buff <= buffer;
            buffer <= data;  <<< driver 3
        end
    end

您有触发器、锁存器和组合逻辑驱动相同的信号。您需要确保信号由单个 always 块驱动。目前您有未定义的模拟行为，混淆了合成器和 linter（它也是一个合成器）。