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Konstantin Pavlov (pt) 40533743d7 Added altera cookbook
2015-12-15 22:44:58 +03:00

66 lines
2.5 KiB
Verilog

// Copyright 2007 Altera Corporation. All rights reserved.
// Altera products are protected under numerous U.S. and foreign patents,
// maskwork rights, copyrights and other intellectual property laws.
//
// This reference design file, and your use thereof, is subject to and governed
// by the terms and conditions of the applicable Altera Reference Design
// License Agreement (either as signed by you or found at www.altera.com). By
// using this reference design file, you indicate your acceptance of such terms
// and conditions between you and Altera Corporation. In the event that you do
// not agree with such terms and conditions, you may not use the reference
// design file and please promptly destroy any copies you have made.
//
// This reference design file is being provided on an "as-is" basis and as an
// accommodation and therefore all warranties, representations or guarantees of
// any kind (whether express, implied or statutory) including, without
// limitation, warranties of merchantability, non-infringement, or fitness for
// a particular purpose, are specifically disclaimed. By making this reference
// design file available, Altera expressly does not recommend, suggest or
// require that this reference design file be used in combination with any
// other product not provided by Altera.
/////////////////////////////////////////////////////////////////////////////
// baeckler - 04-20-2007
// shift "in" left until the most significant bit is a "1"
// pass the shifted value, and number of shifts required
// to the output.
module scale_up (in,out,distance);
parameter WIDTH = 16;
parameter WIDTH_DIST = 4;
input [WIDTH-1:0] in;
output [WIDTH-1:0] out;
output [WIDTH_DIST-1:0] distance;
wire [(WIDTH_DIST+1) * WIDTH-1:0] shift_layers;
assign shift_layers [WIDTH-1:0] = in;
genvar i;
generate
for (i=0;i<WIDTH_DIST;i=i+1)
begin : shft
wire [WIDTH-1:0] layer_in;
wire [WIDTH-1:0] shifted_out;
wire [WIDTH-1:0] layer_out;
assign layer_in = shift_layers[(i+1)*WIDTH-1:i*WIDTH];
// are there ones in the upper part?
wire shift_desired = ~|(layer_in[WIDTH-1:WIDTH-(1 << (WIDTH_DIST-1-i))]);
assign distance[(WIDTH_DIST-1-i)] = shift_desired;
// barrel shifter
assign shifted_out = layer_in << (1 << (WIDTH_DIST-1-i));
assign layer_out = shift_desired ? shifted_out : layer_in;
assign shift_layers[(i+2)*WIDTH-1:(i+1)*WIDTH] = layer_out;
end
endgenerate
assign out = shift_layers[(WIDTH_DIST+1)*WIDTH-1 : WIDTH_DIST*WIDTH];
endmodule