HDLBits-Bcdadd100问题

知识点

reg [31:0] vect;
vect[ 0 +:8];       # 等同vect [7:0]
vect[15 -:8];       # 等同vect[15:8]

reg [0:31] vect;
vect[ 0 +:8];        # 等同vect[0: 7]
vect[15 -:8];       # 等同vect[8:15]

第一次回答

module top_module( 
    input [399:0] a, b,
    input cin,
    output cout,
    output [399:0] sum );
    
    genvar i;
    generate
        for(i=0;i<100;i=i+1) begin:bcd_fadd_arr
            bcd_fadd u_bcd_fadd(
                a[i*4 +: 4],
                b[i*4 +: 4],
                i==0?cin:co[i-1],
                i==99?cout:co[i],
                sum[i]
                );
        end
    endgenerate
    
endmodule

第一次结果

Error (10161): Verilog HDL error at top_module.v(13): object "co" is not declared. Verify the object name is correct. If the name is correct, declare the object. File: /home/h/work/hdlbits.8369168/top_module.v Line: 13
Error (10161): Verilog HDL error at top_module.v(14): object "co" is not declared. Verify the object name is correct. If the name is correct, declare the object. File: /home/h/work/hdlbits.8369168/top_module.v Line: 14

第二次回答

module top_module( 
    input [399:0] a, b,
    input cin,
    output cout,
    output [399:0] sum );
    
    wire co[99:0];
    
    genvar i;
    generate
        for(i=0;i<100;i=i+1) begin:bcd_fadd_arr
            bcd_fadd u_bcd_fadd(
                a[i*4 +: 4],
                b[i*4 +: 4],
                i==0?cin:co[i-1],
                i==99?cout:co[i],
                sum[i]
                );
        end
    endgenerate
    
endmodule

第二次结果

# Hint: Output 'cout' has no mismatches.
# Hint: Output 'sum' has 407 mismatches. First mismatch occurred at time 5.
# Hint: Total mismatched samples is 407 out of 411 samples

第三次回答

module top_module( 
    input [399:0] a, b,
    input cin,
    output cout,
    output [399:0] sum );
    
    wire co[99:0];
    
    genvar i;
    generate
        for(i=0;i<100;i=i+1) begin:bcd_fadd_arr
            bcd_fadd u_bcd_fadd(
                a[i*4 +: 4],
                b[i*4 +: 4],
                i==0?cin:co[i-1],
                i==99?cout:co[i],
                sum[i*4 +:4]
                );
        end
    endgenerate
    
endmodule

第三次结果

Status: Success!

原文地址：http://www.cnblogs.com/ptzcarl/p/16907609.html