HDLbits:Fsm onehot

这道题理解有误,以为s0=10'b0000000001,s0=10'b0000000010,写成了如下的代码(有误):

module top_module(
    input in,
    input [9:0] state,
    output [9:0] next_state,
    output out1,
    output out2);
    
    parameter s0=10'b0000000001,s1=10'b0000000010,s2=10'b0000000100,s3=10'b0000001000,s4=10'b0000010000,
    s5=10'b0000100000,s6=10'b0001000000,s7=10'b0010000000,s8=10'b0100000000,s9=10'b1000000000,s_defualt=10'b0000000000;
    
    always@(*)begin
        case(state)
            s0: next_state = in?s1:s0;
            s1: next_state = in?s2:s0;
            s2: next_state = in?s3:s0;
            s3: next_state = in?s4:s0;   
            s4: next_state = in?s5:s0;
    		s5: next_state = in?s6:s8;
            s6: next_state = in?s7:s9;
            s7: next_state = in?s7:s0;
            s8: next_state = in?s1:s0;
            s9: next_state = in?s1:s0;
            default:next_state = s_defualt;
        endcase
    end
                
    assign out1 = (state == s8 ||state == s9); 
    assign out2 = (state == s7 ||state == s9);       

endmodule

后来发现其实是state[0]表示s0,state[1]表示s1,但并没说其他位一定为0,正确答案如下:

module top_module(
    input in,
    input [9:0] state,
    output [9:0] next_state,
    output out1,
    output out2);
    
    assign next_state[0] = (state[1] | state[2] | state[3] | state[4] | state[7]| state[8]| state[9]| state[0])& ~in;
    assign next_state[1] = (state[8] | state[9] | state[0]) & in;  
    assign next_state[2] = state[1] & in;  
    assign next_state[3] = state[2] & in;  
    assign next_state[4] = state[3] & in;  
    assign next_state[5] =   state[4] & in;        
    assign next_state[6] =   state[5] & in;   
    assign next_state[7] =   (state[7] | state[6])  & in;   
    assign next_state[8] =  state[5] & ~in;   
    assign next_state[9] = state[6] & ~in;
    
    assign out1 =(state[8]==1 || state[9]==1);
    assign out2 =(state[7]==1 || state[9]==1);
endmodule

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