1// -*- verilog -*- 2// 3// USRP - Universal Software Radio Peripheral 4// 5// Copyright (C) 2003, 2007 Matt Ettus 6// 7// This program is free software; you can redistribute it and/or modify 8// it under the terms of the GNU General Public License as published by 9// the Free Software Foundation; either version 2 of the License, or 10// (at your option) any later version. 11// 12// This program is distributed in the hope that it will be useful, 13// but WITHOUT ANY WARRANTY; without even the implied warranty of 14// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15// GNU General Public License for more details. 16// 17// You should have received a copy of the GNU General Public License 18// along with this program; if not, write to the Free Software 19// Foundation, Inc., 51 Franklin Street, Boston, MA 02110-1301 USA 20// 21 22module cordic_z24(clock, reset, enable, xi, yi, zi, xo, yo, zo ); 23 parameter bitwidth = 16; 24 parameter stages = 19; 25 localparam zwidth = 24; 26 27 input clock; 28 input reset; 29 input enable; 30 input [bitwidth-1:0] xi, yi; 31 output [bitwidth-1:0] xo, yo; 32 input [zwidth-1:0] zi; 33 output [zwidth-1:0] zo; 34 35 reg [bitwidth+1:0] x0,y0; 36 reg [zwidth-2:0] z0; 37 wire [bitwidth+1:0] x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15,x16,x17,x18,x19,x20; 38 wire [bitwidth+1:0] y1,y2,y3,y4,y5,y6,y7,y8,y9,y10,y11,y12,y13,y14,y15,y16,y17,y18,y19,y20; 39 wire [zwidth-2:0] z1,z2,z3,z4,z5,z6,z7,z8,z9,z10,z11,z12,z13,z14,z15,z16,z17,z18,z19,z20; 40 41 wire [bitwidth+1:0] xi_ext = {{2{xi[bitwidth-1]}},xi}; 42 wire [bitwidth+1:0] yi_ext = {{2{yi[bitwidth-1]}},yi}; 43 44 // Compute consts. Would be easier if vlog had atan... 45 // see gen_cordic_consts.py 46 47 // constants for 24 bit wide phase 48 localparam c00 = 23'd2097152; 49 localparam c01 = 23'd1238021; 50 localparam c02 = 23'd654136; 51 localparam c03 = 23'd332050; 52 localparam c04 = 23'd166669; 53 localparam c05 = 23'd83416; 54 localparam c06 = 23'd41718; 55 localparam c07 = 23'd20860; 56 localparam c08 = 23'd10430; 57 localparam c09 = 23'd5215; 58 localparam c10 = 23'd2608; 59 localparam c11 = 23'd1304; 60 localparam c12 = 23'd652; 61 localparam c13 = 23'd326; 62 localparam c14 = 23'd163; 63 localparam c15 = 23'd81; 64 localparam c16 = 23'd41; 65 localparam c17 = 23'd20; 66 localparam c18 = 23'd10; 67 localparam c19 = 23'd5; 68 localparam c20 = 23'd3; 69 localparam c21 = 23'd1; 70 localparam c22 = 23'd1; 71 localparam c23 = 23'd0; 72 73 always @(posedge clock) 74 if(reset) 75 begin 76 x0 <= 0; y0 <= 0; z0 <= 0; 77 end 78 else// if(enable) 79 begin 80 z0 <= zi[zwidth-2:0]; 81 case (zi[zwidth-1:zwidth-2]) 82 2'b00, 2'b11 : 83 begin 84 x0 <= xi_ext; 85 y0 <= yi_ext; 86 end 87 2'b01, 2'b10 : 88 begin 89 x0 <= -xi_ext; 90 y0 <= -yi_ext; 91 end 92 endcase // case(zi[zwidth-1:zwidth-2]) 93 end // else: !if(reset) 94 95 // FIXME need to handle variable number of stages 96 // This would be easier if arrays worked better in vlog... 97 98 cordic_stage #(bitwidth+2,zwidth-1,0) cordic_stage0 (clock,reset,enable,x0,y0,z0,c00,x1,y1,z1); 99 cordic_stage #(bitwidth+2,zwidth-1,1) cordic_stage1 (clock,reset,enable,x1,y1,z1,c01,x2,y2,z2); 100 cordic_stage #(bitwidth+2,zwidth-1,2) cordic_stage2 (clock,reset,enable,x2,y2,z2,c02,x3,y3,z3); 101 cordic_stage #(bitwidth+2,zwidth-1,3) cordic_stage3 (clock,reset,enable,x3,y3,z3,c03,x4,y4,z4); 102 cordic_stage #(bitwidth+2,zwidth-1,4) cordic_stage4 (clock,reset,enable,x4,y4,z4,c04,x5,y5,z5); 103 cordic_stage #(bitwidth+2,zwidth-1,5) cordic_stage5 (clock,reset,enable,x5,y5,z5,c05,x6,y6,z6); 104 cordic_stage #(bitwidth+2,zwidth-1,6) cordic_stage6 (clock,reset,enable,x6,y6,z6,c06,x7,y7,z7); 105 cordic_stage #(bitwidth+2,zwidth-1,7) cordic_stage7 (clock,reset,enable,x7,y7,z7,c07,x8,y8,z8); 106 cordic_stage #(bitwidth+2,zwidth-1,8) cordic_stage8 (clock,reset,enable,x8,y8,z8,c08,x9,y9,z9); 107 cordic_stage #(bitwidth+2,zwidth-1,9) cordic_stage9 (clock,reset,enable,x9,y9,z9,c09,x10,y10,z10); 108 cordic_stage #(bitwidth+2,zwidth-1,10) cordic_stage10 (clock,reset,enable,x10,y10,z10,c10,x11,y11,z11); 109 cordic_stage #(bitwidth+2,zwidth-1,11) cordic_stage11 (clock,reset,enable,x11,y11,z11,c11,x12,y12,z12); 110 cordic_stage #(bitwidth+2,zwidth-1,12) cordic_stage12 (clock,reset,enable,x12,y12,z12,c12,x13,y13,z13); 111 cordic_stage #(bitwidth+2,zwidth-1,13) cordic_stage13 (clock,reset,enable,x13,y13,z13,c13,x14,y14,z14); 112 cordic_stage #(bitwidth+2,zwidth-1,14) cordic_stage14 (clock,reset,enable,x14,y14,z14,c14,x15,y15,z15); 113 cordic_stage #(bitwidth+2,zwidth-1,15) cordic_stage15 (clock,reset,enable,x15,y15,z15,c15,x16,y16,z16); 114 cordic_stage #(bitwidth+2,zwidth-1,16) cordic_stage16 (clock,reset,enable,x16,y16,z16,c16,x17,y17,z17); 115 cordic_stage #(bitwidth+2,zwidth-1,17) cordic_stage17 (clock,reset,enable,x17,y17,z17,c17,x18,y18,z18); 116 cordic_stage #(bitwidth+2,zwidth-1,18) cordic_stage18 (clock,reset,enable,x18,y18,z18,c18,x19,y19,z19); 117 cordic_stage #(bitwidth+2,zwidth-1,19) cordic_stage19 (clock,reset,enable,x19,y19,z19,c19,x20,y20,z20); 118 119 assign xo = x20[bitwidth:1]; 120 assign yo = y20[bitwidth:1]; 121 assign zo = z20; 122 123endmodule // cordic 124 125