//=======================================================================
|
//=======================================================================
|
// Project Monophony
|
// Project Monophony
|
// Wire-Frame 3D Graphics Accelerator IP Core
|
// Wire-Frame 3D Graphics Accelerator IP Core
|
//
|
//
|
// File:
|
// File:
|
// fm_3d_fcnv.v
|
// fm_3d_fcnv.v
|
//
|
//
|
// Abstract:
|
// Abstract:
|
// 3D float conversion IEEE single floating point number to
|
// 3D float conversion IEEE single floating point number to
|
// 22-bits floating point number
|
// 22-bits floating point number
|
//
|
//
|
// Author:
|
// Author:
|
// Kenji Ishimaru (kenji.ishimaru@prtissimo.com)
|
// Kenji Ishimaru (info.wf3d@gmail.com)
|
//
|
//
|
//======================================================================
|
//======================================================================
|
//
|
//
|
// Copyright (c) 2015, Kenji Ishimaru
|
// Copyright (c) 2015, Kenji Ishimaru
|
// All rights reserved.
|
// All rights reserved.
|
//
|
//
|
// Redistribution and use in source and binary forms, with or without
|
// Redistribution and use in source and binary forms, with or without
|
// modification, are permitted provided that the following conditions are met:
|
// modification, are permitted provided that the following conditions are met:
|
//
|
//
|
// -Redistributions of source code must retain the above copyright notice,
|
// -Redistributions of source code must retain the above copyright notice,
|
// this list of conditions and the following disclaimer.
|
// this list of conditions and the following disclaimer.
|
// -Redistributions in binary form must reproduce the above copyright notice,
|
// -Redistributions in binary form must reproduce the above copyright notice,
|
// this list of conditions and the following disclaimer in the documentation
|
// this list of conditions and the following disclaimer in the documentation
|
// and/or other materials provided with the distribution.
|
// and/or other materials provided with the distribution.
|
//
|
//
|
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
|
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
|
// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
|
// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
|
// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
|
// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
|
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
|
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
|
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
|
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
|
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
|
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
|
// OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
|
// OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
|
// WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
|
// WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
|
// OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
|
// OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
|
// EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
// EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
//
|
//
|
// Revision History
|
// Revision History
|
|
|
module fm_3d_fcnv (
|
module fm_3d_fcnv (
|
i_f32,
|
i_f32,
|
o_f22
|
o_f22
|
);
|
);
|
|
|
////////////////////////////
|
////////////////////////////
|
// I/O definition
|
// I/O definition
|
////////////////////////////
|
////////////////////////////
|
input [31:0] i_f32;
|
input [31:0] i_f32;
|
output [21:0] o_f22;
|
output [21:0] o_f22;
|
|
|
////////////////////////////
|
////////////////////////////
|
// assign
|
// assign
|
////////////////////////////
|
////////////////////////////
|
assign o_f22 = f_f32_to_f22(i_f32);
|
assign o_f22 = f_f32_to_f22(i_f32);
|
////////////////////////////
|
////////////////////////////
|
// function
|
// function
|
////////////////////////////
|
////////////////////////////
|
function [21:0] f_f32_to_f22;
|
function [21:0] f_f32_to_f22;
|
input [31:0] f32;
|
input [31:0] f32;
|
reg s;
|
reg s;
|
reg [7:0] e8;
|
reg [7:0] e8;
|
reg [8:0] e8d; // width sign bit
|
reg [8:0] e8d; // width sign bit
|
reg [4:0] e5;
|
reg [4:0] e5;
|
reg [23:0] m23;
|
reg [23:0] m23;
|
reg [14:0] m15;
|
reg [14:0] m15;
|
reg carry;
|
reg carry;
|
reg zf;
|
reg zf;
|
begin
|
begin
|
s = f32[31];
|
s = f32[31];
|
e8 = f32[30:23];
|
e8 = f32[30:23];
|
zf = (e8 == 8'h00);
|
zf = (e8 == 8'h00);
|
m23 = f32[22:0];
|
m23 = f32[22:0];
|
{carry,m15} = m23[22:8] + m23[7];
|
{carry,m15} = m23[22:8] + m23[7];
|
e8d = e8 - 112 + carry; // -127+15 + carry
|
e8d = e8 - 112 + carry; // -127+15 + carry
|
if (zf|e8d[8]) begin
|
if (zf|e8d[8]) begin
|
e5 = 5'h0;
|
e5 = 5'h0;
|
end else begin
|
end else begin
|
e5 = e8d[4:0];
|
e5 = e8d[4:0];
|
end
|
end
|
f_f32_to_f22 = {s,e5,!(zf|e8d[8]),m15};
|
f_f32_to_f22 = {s,e5,!(zf|e8d[8]),m15};
|
end
|
end
|
endfunction
|
endfunction
|
|
|
endmodule
|
endmodule
|
|
|
