下面给出一个CORDIC算法在圆周系统下的向量模式下获取角度的Verilog 程序：

/*==============================================================================*\
        Filename : Cordic.v
        Discription : 坐标旋转数字计算方法。通过该算法，对输入的向量坐标进行9次迭代
     计算，得到该向量的模值和相角。
        
\*==============================================================================*/

module CORDIC
 (
  Clk_20m,
  _Rst,
  Cordic_start,
  Ug_d,  
  Ug_q,
  Ug,
  Delta

 );

 input Clk_20m,
   _Rst,
   Cordic_start;  //CORDIC变换启动标志
 
 input[15:0] Ug_d,  //输出电压的d轴分量
    Ug_q;  //输出电压的q轴分量
 output[15:0] Ug;  //输出电压向量的模值
 output[13:0] Delta;  //输出电压向量的相角
 
 wire[31:0] Ug_tmp;
 reg[3:0] Times;  //迭代次数累加器
 reg[15:0] Ug_d_tmp,  //输出电压d轴分量的中间迭代结果
    Ug_q_tmp;  //输出电压q轴分量的中间迭代结果
    
 reg[13:0] //Delta,
    Delta_tmp;  //相位角旋转累加寄存器
 
 
// assign Ug = ( Ug_d_tmp>>1 ) + ( Ug_d_tmp>>3 ) - ( Ug_d_tmp>>6 ) - ( Ug_d_tmp>>9 );
 
 //对电压模值进行比例系数调整，得到实际模值的32倍
// assign Ug_tmp[31:0] = Ug_d_tmp[15:0] * 16‘d48224;//d39797;
 assign Ug_tmp[31:0] = Ug_d_tmp[15:0] * 16‘d45208;
 assign Ug[15:0] = Ug_tmp[31:16];
 

 //输出电压向量的相角即为CORDIC算法输出的旋转角
 assign Delta = Delta_tmp;
/* 
 always @( posedge Clk_20m or negedge _Rst )
 begin
  if ( !_Rst )
   Delta <= 14‘h0;
  else if ( Delta_tmp <= 14‘h6 )
    Delta <= Delta_tmp;
   else if ( Delta_tmp <= 14‘h1fff )
     Delta <= 14‘h6;
    else if ( Delta_tmp <= 14‘h3ffa )
      Delta <= 14‘h3ffa;
     else
      Delta <= Delta_tmp;

  else
   Delta <= 14‘h6;
      
 end

*/

 always @( posedge Clk_20m or negedge _Rst ) 
 begin
  if ( !_Rst )
   begin
   Times[3:0] <= 4‘hf;
   Ug_d_tmp[15:0] <= 16‘h0;
   Ug_q_tmp[15:0] <= 16‘h0;
   Delta_tmp[13:0] <= 14‘h0;
   end
  else if ( Cordic_start )  //启动CORDIC变换
    begin
    Times[3:0] <= 4‘h0;
    Ug_d_tmp <= Ug_d;
    Ug_q_tmp <= Ug_q;
    Delta_tmp <= 14‘h0;
    end
    else if ( Times <= 4‘d9 )  //开始迭代计算
     begin
     Times[3:0] <= Times[3:0] + 4‘h1;  //迭代次数加1
     case ( Times )
     4‘h0:

//Ug_q_tmp[15] 符号位
      if ( Ug_q_tmp[15] )  //旋转的目标是使Ug_q_tmp趋近于0,
            //根据对Ug_q_tmp符号的判断，决定正向旋转还是反向旋转
       begin
       Ug_d_tmp <= Ug_d_tmp - Ug_q_tmp;  //重新计算新的d轴分量
       Ug_q_tmp <= Ug_q_tmp + Ug_d_tmp;  //重新计算新的q轴分量
       Delta_tmp <= Delta_tmp - 14‘hB40;  //对相位角进行累加计算
       end
      else
       begin
       Ug_d_tmp <= Ug_d_tmp + Ug_q_tmp;
       Ug_q_tmp <= Ug_q_tmp - Ug_d_tmp;
       Delta_tmp <= Delta_tmp + 14‘hB40;    //(2880/64)=45
       end
     4‘h1:
      if ( Ug_q_tmp[15] )
       begin
       Ug_d_tmp <= Ug_d_tmp - { Ug_q_tmp[15], Ug_q_tmp[15:1] };
       Ug_q_tmp <= Ug_q_tmp + { Ug_d_tmp[15], Ug_d_tmp[15:1] };
       Delta_tmp <= Delta_tmp - 14‘h6A4;  // (1700/64)=26.5625
       end
      else
       begin
       Ug_d_tmp <= Ug_d_tmp + { Ug_q_tmp[15], Ug_q_tmp[15:1] };
       Ug_q_tmp <= Ug_q_tmp - { Ug_d_tmp[15], Ug_d_tmp[15:1] };
       Delta_tmp <= Delta_tmp + 14‘h6A4; // 
       end
     4‘h2:
      if ( Ug_q_tmp[15] )
       begin
       Ug_d_tmp <= Ug_d_tmp - { {2{Ug_q_tmp[15]}}, Ug_q_tmp[15:2] };
       Ug_q_tmp <= Ug_q_tmp + { {2{Ug_d_tmp[15]}}, Ug_d_tmp[15:2] };
       Delta_tmp <= Delta_tmp - 14‘h382; // (382/64=14.03125)
       end
      else
       begin
       Ug_d_tmp <= Ug_d_tmp + { {2{Ug_q_tmp[15]}}, Ug_q_tmp[15:2] };
       Ug_q_tmp <= Ug_q_tmp - { {2{Ug_d_tmp[15]}}, Ug_d_tmp[15:2] };
       Delta_tmp <= Delta_tmp + 14‘h382;
       end
     4‘h3:
      if ( Ug_q_tmp[15] )
       begin
       Ug_d_tmp <= Ug_d_tmp - { {3{Ug_q_tmp[15]}}, Ug_q_tmp[15:3] };
       Ug_q_tmp <= Ug_q_tmp + { {3{Ug_d_tmp[15]}}, Ug_d_tmp[15:3] };
       Delta_tmp <= Delta_tmp - 14‘h1c8; // (382/64=14.03125)
       end
      else
       begin
       Ug_d_tmp <= Ug_d_tmp + { {3{Ug_q_tmp[15]}}, Ug_q_tmp[15:3] };
       Ug_q_tmp <= Ug_q_tmp - { {3{Ug_d_tmp[15]}}, Ug_d_tmp[15:3] };
       Delta_tmp <= Delta_tmp + 14‘h1c8; // (456/64=7.125)
       end
     4‘h4:
      if ( Ug_q_tmp[15] )
       begin
       Ug_d_tmp <= Ug_d_tmp - { {4{Ug_q_tmp[15]}}, Ug_q_tmp[15:4] };
       Ug_q_tmp <= Ug_q_tmp + { {4{Ug_d_tmp[15]}}, Ug_d_tmp[15:4] };
       Delta_tmp <= Delta_tmp - 14‘hE5; //(229/64=3.578125)
       end
      else
       begin
       Ug_d_tmp <= Ug_d_tmp + { {4{Ug_q_tmp[15]}}, Ug_q_tmp[15:4] };
       Ug_q_tmp <= Ug_q_tmp - { {4{Ug_d_tmp[15]}}, Ug_d_tmp[15:4] };
       Delta_tmp <= Delta_tmp + 14‘hE5;
       end
     4‘h5:
      if ( Ug_q_tmp[15] )
       begin
       Ug_d_tmp <= Ug_d_tmp - { {5{Ug_q_tmp[15]}}, Ug_q_tmp[15:5] };
       Ug_q_tmp <= Ug_q_tmp + { {5{Ug_d_tmp[15]}}, Ug_d_tmp[15:5] };
       Delta_tmp <= Delta_tmp - 14‘h72; //(114/64=1.78125)
       end
      else
       begin
       Ug_d_tmp <= Ug_d_tmp + { {5{Ug_q_tmp[15]}}, Ug_q_tmp[15:5] };
       Ug_q_tmp <= Ug_q_tmp - { {5{Ug_d_tmp[15]}}, Ug_d_tmp[15:5] };
       Delta_tmp <= Delta_tmp + 14‘h72;
       end
     4‘h6:
      if ( Ug_q_tmp[15] )
       begin
       Ug_d_tmp <= Ug_d_tmp - { {6{Ug_q_tmp[15]}}, Ug_q_tmp[15:6] };
       Ug_q_tmp <= Ug_q_tmp + { {6{Ug_d_tmp[15]}}, Ug_d_tmp[15:6] };
       Delta_tmp <= Delta_tmp - 14‘h39;//(57/64=0.890625)
       end
      else
       begin
       Ug_d_tmp <= Ug_d_tmp + { {6{Ug_q_tmp[15]}}, Ug_q_tmp[15:6] };
       Ug_q_tmp <= Ug_q_tmp - { {6{Ug_d_tmp[15]}}, Ug_d_tmp[15:6] };
       Delta_tmp <= Delta_tmp + 14‘h39;
       end
     4‘h7:
      if ( Ug_q_tmp[15] )
       begin
       Ug_d_tmp <= Ug_d_tmp - { {7{Ug_q_tmp[15]}}, Ug_q_tmp[15:7] };
       Ug_q_tmp <= Ug_q_tmp + { {7{Ug_d_tmp[15]}}, Ug_d_tmp[15:7] };
       Delta_tmp <= Delta_tmp - 14‘h1C;//(28/64=0.4375)
       end
      else
       begin
       Ug_d_tmp <= Ug_d_tmp + { {7{Ug_q_tmp[15]}}, Ug_q_tmp[15:7] };
       Ug_q_tmp <= Ug_q_tmp - { {7{Ug_d_tmp[15]}}, Ug_d_tmp[15:7] };
       Delta_tmp <= Delta_tmp + 14‘h1C;
       end
     4‘h8:
      if ( Ug_q_tmp[15] )
       begin
       Ug_d_tmp <= Ug_d_tmp - { {8{Ug_q_tmp[15]}}, Ug_q_tmp[15:8] };
       Ug_q_tmp <= Ug_q_tmp + { {8{Ug_d_tmp[15]}}, Ug_d_tmp[15:8] };
       Delta_tmp <= Delta_tmp - 14‘hE;//(14/64=0.21875)
       end
      else
       begin
       Ug_d_tmp <= Ug_d_tmp + { {8{Ug_q_tmp[15]}}, Ug_q_tmp[15:8] };
       Ug_q_tmp <= Ug_q_tmp - { {8{Ug_d_tmp[15]}}, Ug_d_tmp[15:8] };
       Delta_tmp <= Delta_tmp + 14‘hE;
       end
     4‘h9:
      if ( Ug_q_tmp[15] )
       begin
       Ug_d_tmp <= Ug_d_tmp - { {9{Ug_q_tmp[15]}}, Ug_q_tmp[15:9] };
       Ug_q_tmp <= Ug_q_tmp + { {9{Ug_d_tmp[15]}}, Ug_d_tmp[15:9] };
       Delta_tmp <= Delta_tmp - 14‘h7;
       end
      else
       begin
       Ug_d_tmp <= Ug_d_tmp + { {9{Ug_q_tmp[15]}}, Ug_q_tmp[15:9] };
       Ug_q_tmp <= Ug_q_tmp - { {9{Ug_d_tmp[15]}}, Ug_d_tmp[15:9] };
       Delta_tmp <= Delta_tmp + 14‘h7; //(7/64=0.109375)
       end
     default:  //缺省情况下所有寄存器清零
      begin
      Ug_d_tmp <= 16‘h0;
      Ug_q_tmp <= 16‘h0;
      Delta_tmp <= 14‘h0;
      end
//      ;
     endcase
     end
    else
     Times[3:0] <= 4‘hf;  //迭代计算完毕，结束CORDIC算法，迭代次数置复位值
 
 
 end

 

endmodule