cos.txt

FPGA实现正弦

module cordic(clk, phi, cos, sin);
        parameter  W = 13, W_Z = 14;
        input         clk;
        input [W_Z-1:0]  phi;
        output[W-1:0]            cos, sin;
        
        reg [W-1:0]   cos, sin;
        reg [W-1:0]   x[8:0], y[8:0];
        reg [W_Z-1:0] z[7:0];
        always @(posedge clk)begin
                x[0] <= 13'h4D;                  // 修正CORDIC算法的比例因子，An的倒数
                y[0] <= 13'h00;        
                z[0] <= phi;
                // 旋转45度
                if(z[0][W_Z-1]) begin 
                        x[1] <= x[0] + y[0];        
                        y[1] <= y[0] - x[0];        
                        z[1] <= z[0] + 14'h65;
                end
                else begin 
                        x[1] <= x[0] - y[0];        
                        y[1] <= y[0] + x[0];        
                        z[1] <= z[0] - 14'h65;
                end
                // 旋转26.57度
                if(z[1][W_Z-1])begin 
                        x[2] <= x[1] + {{1{y[1][W-1]}}, y[1][W-1:1]};
                        y[2] <= y[1] - {{1{x[1][W-1]}}, x[1][W-1:1]};
                        z[2] <= z[1] + 14'h3B;
                end
                else begin 
                        x[2] <= x[1] - {{1{y[1][W-1]}}, y[1][W-1:1]};
                        y[2] <= y[1] + {{1{x[1][W-1]}}, x[1][W-1:1]};
                        z[2] <= z[1] - 14'h3B;
                end
                // 旋转14.04度
                if(z[2][W_Z-1])begin 
                        x[3] <= x[2] + {{2{y[2][W-1]}}, y[2][W-1:2]};
                        y[3] <= y[2] - {{2{x[2][W-1]}}, x[2][W-1:2]};
                        z[3] <= z[2] + 14'h1F;
                end
                else begin 
                        x[3] <= x[2] - {{2{y[2][W-1]}}, y[2][W-1:2]};
                        y[3] <= y[2] + {{2{x[2][W-1]}}, x[2][W-1:2]};
                        z[3] <= z[2] - 14'h1F;
                end
                // 旋转7.13度
                if(z[3][W_Z-1])begin 
                        x[4] <= x[3] + {{3{y[3][W-1]}}, y[3][W-1:3]};
                        y[4] <= y[3] - {{3{x[3][W-1]}}, x[3][W-1:3]};
                        z[4] <= z[3] + 14'h10;
                end
                else begin 
                        x[4] <= x[3] - {{3{y[3][W-1]}}, y[3][W-1:3]};
                        y[4] <= y[3] + {{3{x[3][W-1]}}, x[3][W-1:3]};
                        z[4] <= z[3] - 14'h10;
                end
                // 旋转3.58度
                if(z[4][W_Z-1])begin 
                        x[5] <= x[4] + {{4{y[4][W-1]}}, y[4][W-1:4]};
                        y[5] <= y[4] - {{4{x[4][W-1]}}, x[4][W-1:4]};
                        z[5] <= z[4] + 14'h8;
                end
                else begin 
                        x[5] <= x[4] - {{4{y[4][W-1]}}, y[4][W-1:4]};
                        y[5] <= y[4] + {{4{x[4][W-1]}}, x[4][W-1:4]};
                        z[5] <= z[4] - 14'h8;
                end
                // 旋转1.79度
                if(z[5][W_Z-1])begin 
                        x[6] <= x[5] + {{5{y[5][W-1]}}, y[5][W-1:5]};
                        y[6] <= y[5] - {{5{x[5][W-1]}}, x[5][W-1:5]};
                        z[6] <= z[5] + 14'h4;
                end
                else begin 
                        x[6] <= x[5] - {{5{y[5][W-1]}}, y[5][W-1:5]};
                        y[6] <= y[5] + {{5{x[5][W-1]}}, x[5][W-1:5]};
                        z[6] <= z[5] - 14'h4;
                end
                // 旋转0.90度
                if(z[6][W_Z-1])begin 
                        x[7] <= x[6] + {{6{y[6][W-1]}}, y[6][W-1:6]};
                        y[7] <= y[6] - {{6{x[6][W-1]}},        x[6][W-1:6]};
                        z[7] <= z[6] + 14'h2;
                end
                else begin 
                        x[7] <= x[6] - {{6{y[6][W-1]}}, y[6][W-1:6]};
                        y[7] <= y[6] + {{6{x[6][W-1]}}, x[6][W-1:6]};
                        z[7] <= z[6] - 14'h2;
                end
                // 旋转0.45度
                if(z[7][W_Z-1])begin 
                        x[8] <= x[7] + {{7{y[7][W-1]}}, y[7][W-1:7]};
                        y[8] <= y[7] - {{7{x[7][W-1]}}, x[7][W-1:7]};
                end
                else begin 
                        x[8] <= x[7] - {{7{y[7][W-1]}}, y[7][W-1:7]};
                        y[8] <= y[7] + {{7{x[7][W-1]}}, x[7][W-1:7]};
                end
                cos <= x[8];
                sin <= y[8];
        end
endmodule