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[/] [ft816float/] [trunk/] [rtl/] [verilog/] [F80ToF32.v] - Blame information for rev 23

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`timescale 1ns / 1ps
// ============================================================================
//        __
//   \\__/ o\    (C) 2006-2019  Robert Finch, Waterloo
//    \  __ /    All rights reserved.
//     \/_//     robfinch<remove>@finitron.ca
//       ||
//
//
//
// This source file is free software: you can redistribute it and/or modify 
// it under the terms of the GNU Lesser General Public License as published 
// by the Free Software Foundation, either version 3 of the License, or     
// (at your option) any later version.                                      
//                                                                          
// This source file is distributed in the hope that it will be useful,      
// but WITHOUT ANY WARRANTY; without even the implied warranty of           
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the            
// GNU General Public License for more details.                             
//                                                                          
// You should have received a copy of the GNU General Public License        
// along with this program.  If not, see <http://www.gnu.org/licenses/>.    
//                                                                          
// ============================================================================
 
module F80ToF32(a, o);
input [79:0] a;
output [31:0] o;
 
reg signo;
reg [7:0] expo;
reg [22:0] mano;
 
assign o = {signo,expo,mano};
 
wire signi;
wire [14:0] expi;
wire [63:0] mani;
wire xinf;      // exponent infinite
wire vz;        // value zero
wire xz;        // exponent zero
 
fpDecomp #(80) u1 (.i(a), .sgn(signi), .exp(expi), .man(mani), .xinf(xinf), .xz(xz), .vz(vz) );
 
always @*
begin
  // sign out always just = sign in
  signo = signi;
 
  // special check for zero
  if (vz) begin
    expo <= 0;
    mano <= 0;
  end
  // convert infinity / nan
  // infinity in = infinity out
  else if (xinf) begin
    expo <= 8'h7f;
    mano <= mani[63:41];
  end
  // convert denormal
  // a denormal was really a number with an exponent of -126
  // this value is easily represented in the double format
  // it may be possible to normalize the value if it isn't
  // zero
  else if (xz) begin
    expo <= 8'h00;
    mano <= 23'h0;
  end
  // convert typical number
  // adjust exponent, copy mantissa
  else begin
        if (expi < 15'h3fff - 8'h7f) begin
                expo <= 8'h00;  // zero
                mano <= 23'h0;
        end
        else if (expi > 15'h3fff + 8'h7f) begin
                expo <= 8'hFF;  // Infinity
                mano <= 23'h0;
        end
        else begin
        expo <= expi - 15'h3fff + 8'h7f;
        mano <= mani[63:41];
    end
  end
end
 
endmodule

Line No.	Rev	Author	Line
1	16	robfinch	`timescale 1ns / 1ps
2			`// ============================================================================`
3			`// __`
4			`// \\__/ o\ (C) 2006-2019 Robert Finch, Waterloo`
5			`// \ __ / All rights reserved.`
6			`// \/_// robfinch<remove>@finitron.ca`
7			`// \|\|`
8			`//`
9			`//`
10			`//`
11			`// This source file is free software: you can redistribute it and/or modify`
12			`// it under the terms of the GNU Lesser General Public License as published`
13			`// by the Free Software Foundation, either version 3 of the License, or`
14			`// (at your option) any later version.`
15			`//`
16			`// This source file is distributed in the hope that it will be useful,`
17			`// but WITHOUT ANY WARRANTY; without even the implied warranty of`
18			`// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the`
19			`// GNU General Public License for more details.`
20			`//`
21			`// You should have received a copy of the GNU General Public License`
22			`// along with this program. If not, see <http://www.gnu.org/licenses/>.`
23			`//`
24			`// ============================================================================`
25
26			`module F80ToF32(a, o);`
27			`input [79:0] a;`
28			`output [31:0] o;`
29
30			`reg signo;`
31			`reg [7:0] expo;`
32			`reg [22:0] mano;`
33
34			`assign o = {signo,expo,mano};`
35
36			`wire signi;`
37			`wire [14:0] expi;`
38			`wire [63:0] mani;`
39			`wire xinf; // exponent infinite`
40			`wire vz; // value zero`
41			`wire xz; // exponent zero`
42
43			`fpDecomp #(80) u1 (.i(a), .sgn(signi), .exp(expi), .man(mani), .xinf(xinf), .xz(xz), .vz(vz) );`
44
45			`always @*`
46			`begin`
47			`// sign out always just = sign in`
48			`signo = signi;`
49
50			`// special check for zero`
51			`if (vz) begin`
52			`expo <= 0;`
53			`mano <= 0;`
54			`end`
55			`// convert infinity / nan`
56			`// infinity in = infinity out`
57			`else if (xinf) begin`
58			`expo <= 8'h7f;`
59			`mano <= mani[63:41];`
60			`end`
61			`// convert denormal`
62			`// a denormal was really a number with an exponent of -126`
63			`// this value is easily represented in the double format`
64			`// it may be possible to normalize the value if it isn't`
65			`// zero`
66			`else if (xz) begin`
67			`expo <= 8'h00;`
68			`mano <= 23'h0;`
69			`end`
70			`// convert typical number`
71			`// adjust exponent, copy mantissa`
72			`else begin`
73			`if (expi < 15'h3fff - 8'h7f) begin`
74			`expo <= 8'h00; // zero`
75			`mano <= 23'h0;`
76			`end`
77			`else if (expi > 15'h3fff + 8'h7f) begin`
78			`expo <= 8'hFF; // Infinity`
79			`mano <= 23'h0;`
80			`end`
81			`else begin`
82			`expo <= expi - 15'h3fff + 8'h7f;`
83			`mano <= mani[63:41];`
84			`end`
85			`end`
86			`end`
87
88			`endmodule`

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[/] [ft816float/] [trunk/] [rtl/] [verilog/] [F80ToF32.v] - Blame information for rev 23