transmitter.v

实现串并口通信,共有发送和接受两个模块。

module uart1(clk, rst_n, start, inbyte, outdate);
input clk, rst_n, start;
input [7:0] inbyte;
output outdate;
reg outdate;
reg [7:0] store;
reg [3:0] counter;
reg [3:0] st, next_st;
parameter st_0 = 0, st_1 = 1, st_2 = 2, st_3 = 3, st_4 = 4, 
st_5 = 5, st_6 = 6, st_7 = 7, st_8 = 8, st_9 = 9, st_10 = 10, st_11 = 11, st_12 = 12, st_13 = 13;
////////////////////////////////////////
always@(posedge clk or negedge rst_n)
begin
    if(rst_n == 0)
    st <= st_0;
    else
    st <= next_st;
end
////////////////////////////////////////
always@(posedge clk or negedge rst_n)
begin
    if(rst_n == 0)
    next_st <= st_0;
    else
    begin
        case(st)
        st_0:
        begin
            if(start == 1)
            begin
            counter <= 0;
            store <= inbyte;
            next_st <= st_1;
            end
            else
            next_st <= st_0;
        end
        st_1:
        begin
            if(counter == 15)
            begin
            counter <= 0;
            next_st <= st_2;
            end
            else
            begin
            counter <= counter + 1;
            next_st <= st_1;
            end
        end
        st_2:
        begin
            if(counter == 15)
            begin
            counter <= 0;
            next_st <= st_3;
            end
            else
            begin
            counter <= counter + 1;
            next_st <= st_2;
            end
        end
        st_3:
        begin
            if(counter == 15)
            begin
            counter <= 0;
            next_st <= st_4;
            end
            else
            begin
            counter <= counter + 1;
            next_st <= st_3;
            end
        end
        st_4:
        begin
            if(counter == 15)
            begin
            counter <= 0;
            next_st <= st_5;
            end
            else
            begin
            counter <= counter + 1;
            next_st <= st_4;
            end
        end
        st_5:
        begin
            if(counter == 15)
            begin
            counter <= 0;
            next_st <= st_6;
            end
            else
            begin
            counter <= counter + 1;
            next_st <= st_5;
            end
        end
        st_6:
        begin
            if(counter == 15)
            begin
            counter <= 0;
            next_st <= st_7;
            end
            else
            begin
            counter <= counter + 1;
            next_st <= st_6;
            end
        end
        st_7:
        begin
            if(counter == 15)
            begin
            counter <= 0;
            next_st <= st_8;
            end
            else
            begin
            counter <= counter + 1;
            next_st <= st_7;
            end
        end
        st_8:
        begin
            if(counter == 15)
            begin
            counter <= 0;
            next_st <= st_9;
            end
            else
            begin
            counter <= counter + 1;
            next_st <= st_8;
            end
        end
        st_9:
        begin
            if(counter == 15)
            begin
            counter <= 0;
            next_st <= st_10;
            end
            else
            begin
            counter <= counter + 1;
            next_st <= st_9;
            end
        end
        st_10:
        begin
            if(counter == 15)
            begin
            counter <= 0;
            next_st <= st_11;
            end
            else
            begin
            counter <= counter + 1;
            next_st <= st_10;
            end
        end
        st_11:
        begin
            if(counter == 15)
            begin
            counter <= 0;
            next_st <= st_12;
            end
            else
            begin
            counter <= counter + 1;
            next_st <= st_11;
            end
        end
        st_12:
        begin
            if(counter == 15)
            begin
            counter <= 0;
            next_st <= st_13;
            end
            else
            begin
            counter <= counter + 1;
            next_st <= st_12;
            end
        end
        st_13:
        begin
            if(counter == 15)
            begin
            counter <= 0;
            next_st <= st_0;
            end
            else
            begin
            counter <= counter + 1;
            next_st <= st_13;
            end
        end
        default:
        next_st <= st_0;
        endcase
    end
end
/////////////////////////////////////////////////
always@(rst_n or st)
begin
    if(rst_n == 0)
    outdate <= 1;
    else
    case(st)
        st_0:
        outdate <= 1;
        st_1:
        outdate <= 0;
        st_2:
        outdate <= 0;
        st_3:
        outdate <= store[7];
        st_4:
        outdate <= store[6];
        st_5:
        outdate <= store[5];
        st_6:
        outdate <= store[4];
        st_7:
        outdate <= store[3];
        st_8:
        outdate <= store[2];
        st_9:
        outdate <= store[1];
        st_10:
        outdate <= store[0];
        st_11:
        outdate <= (store[7] + store[6] + store[5] + store[4] + store[3] + store[2] + store[1] + store[0])%2;
        st_12:
        outdate <= 0;
        st_13:
        outdate <= 0;
        default:
        outdate <= 1;
        endcase
end
///////////////////////////////////////////////
endmodule