libusrp/fpga/sdr_lib/sign_extend.v

36 lines
1.1 KiB
Verilog

// -*- verilog -*-
//
// USRP - Universal Software Radio Peripheral
//
// Copyright (C) 2003 Matt Ettus
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program 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, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Boston, MA 02110-1301 USA
//
// Sign extension "macro"
// bits_out should be greater than bits_in
module sign_extend (in,out);
parameter bits_in=0; // FIXME Quartus insists on a default
parameter bits_out=0;
input [bits_in-1:0] in;
output [bits_out-1:0] out;
assign out = {{(bits_out-bits_in){in[bits_in-1]}},in};
endmodule